Support a local area computer network 114043 - geeks4learning

Support a local area

computer network

Module 5 – Network Support Skills Author: Rel Date: 27/01/2018 Rev Date: 01/06/2023 Doc Ref: 48573 LM Mod 1 v-1

LEARNER MANUAL PAGE 21

PURPOSE OF THE UNIT STANDARD

This unit standard is intended for people responsible for the provision of day-to-day network

administration and support, including resolution of network user problems, data backup and

restore, production of network performance statistics, provision of network diagnostic

information, and site surveys in a local area network (LAN) environment:

As fundamental knowledge of the areas covered,

For those working in the Information Technology industry in the area of Network

Administration,

As additional knowledge for those wanting to understand the areas covered.

People credited with this unit standard are able to:

Maintain the performance of a local area computer network (LAN);

Execute procedures on a LAN;

Administer security, maintain the supply of consumables, and plan capacity for a LAN;

Maintain the availability of a LAN, and

Manage changes to a LAN.

The performance of all outcomes is to a standard that allows for further learning in this

environment.

LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING

Open. The credit value of this unit standard is calculated assuming a person has the prior

knowledge and skills to apply the principles of administering local and wide area networks.

UNIT STANDARD RANGE

A "local area computer network" (LAN) is a single network of personal computers within the

same area, e.g. an office or building.

"Procedures" are programmes of computer operating commands.

Support a local area computer network 114043

Competence Requirements Page Unit Standard 114043 alignment index Here you will find the different outcomes explained which you need to be proved competent in, in order to complete the Unit Standard 114043.

Unit Standard 114043 25 Maintain the performance of a local area network 30 Execute procedures on a local area computer network 39 Administer security systems for a local area network 53 Maintain the supply of consumables for a local area network 63 Plan capacity for a local area network 68 Maintain the availability of a local area network 81 Make changes to a local area network 87 Self-assessment Once you have completed all the questions after being facilitated, you need to check the progress you have made. If you feel that you are competent in the areas mentioned, you may tick the blocks, if however you feel that you require additional knowledge, you need to indicate so in the block below. Show this to your facilitator and make the necessary arrangements to assist you to become competent.

Unit Standard 114043 – Alignment Index SPECIFIC OUTCOMES AND RELATED ASSESSMENT CRITERIA SO 1 MAINTAIN THE PERFORMANCE OF A LOCAL AREA NETWORK

AC 1 Monitoring and tuning of the network ensures operation and performance meets the manufacturer’s and organisation specifications

AC 2 Network performance problems are resolved according to organisation specifications AC 3 Accurate and up-to-date documentation is maintained of network resource utilisation SO 2 EXECUTE PROCEDURES ON A LOCAL AREA COMPUTER NETWORK

AC 1 The execution ensures that computer output is produced according to organisation specifications

AC 2 Problems with procedures are identified, and action is taken according to organisation specifications

AC 3 Start-up and shutdown of the network are in accordance with the manufacturer’s and organisation specifications

SO 3 ADMINISTER SECURITY SYSTEMS FOR A LOCAL AREA NETWORK

AC 1 Security exposures and violations are identified, and action is taken according to organisation policies, procedures and requirements

AC 2 Back-ups are made according the organisations policies, procedures and specifications

AC 3 Access to the network is provided according to organisation policies, procedures and specifications

SO 4 MAINTAIN THE SUPPLY OF CONSUMABLES FOR A LOCAL AREA NETWORK

AC 1 A forecast of the consumption of computer system consumables is justified using measurement of historical consumption and anticipated events

AC 2 Supply agreements are established so that the consumable supplies are available to meet demand

AC 3 Stocks of consumable supplies meet forecasted demand AC 4 Overstocks of consumable supplies are avoided SO 5 PLAN CAPACITY FOR A LOCAL AREA NETWORK

AC 1 The plan includes a forecast based on documentation of current network resource utilisation, historical growth and future plans

AC 2 The plan includes recommendations for network changes that allow the network to meet the future capacity requirements

AC 3 The plan identifies and explains the feasibility of the recommendations

AC 4 The plan includes a comparison of actual resource usage with forecast usage according to organisation requirements

SO 6 MAINTAIN THE AVAILABILITY OF A LOCAL AREA NETWORK AC 1 The network is available and accessible according to organisation requirements AC 2 Network availability problems are resolved according to organisation specifications SO 7 MANAGE CHANGES TO A LOCAL AREA NETWORK

AC 1 The management ensures that a plan of a proposed change predicts the impact and risks to the organisation associated with the change

AC 2 The management ensures that a plan of a proposed change establishes when the change should occur to minimise the impacts and risks

AC 3 The management includes a contingency plan that allows the network to be restored to a status acceptable to the user in the event of problems with the change

AC 4 Testing establishes the success of the installation and of the changes according to user and organisation requirements

AC 5 The plan ensures that people affected by the change are notified to minimise disruption to their activity

C R I T I C A L C R O S S F I E L D O U T C O M E S

UNIT STANDARD CCFO IDENTIFYING Identify and solve problems in which responses display decisions using critical and creative thinking by acquiring understanding of a problem or situation by breaking it down systematically into its component parts and identifying the relationships between these parts. UNIT STANDARD CCFO WORKING Work effectively with others as a member of a team, group, organisation and/or community by working co-operatively (rather than competitively) with others to achieve a common goal. UNIT STANDARD CCFO COLLECTING Collect, analyse, organise and critically evaluate information by identifying gaps in the available information required to understand a problem or situation and devising means of remedying such gaps. UNIT STANDARD CCFO COMMUNICATING Communicate effectively using visual, mathematical and/or language skills in the modes of organ and/or written presentation by establishing relationships and maintaining contacts with people from a wide variety of backgrounds. UNIT STANDARD CCFO DEMONSTRATING Demonstrate an understanding of the world as a set of related systems by applying quality standards to all tasks undertaken and ensuring that nothing is overlooked.

E S S E N T I A L E M B E D D E D K N O W L E D G E

All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.

SOUTH AFRICAN QUALIFICATIONS AUTHORITY

REGISTERED UNIT STANDARD:

Support a local area computer network

SAQA US ID

UNIT STANDARD TITLE

114043 Support a local area computer network

ORIGINATOR

SGB Information Systems and Technology

FIELD SUBFIELD

Field 10 - Physical, Mathematical, Computer and Life Sciences Information Technology and Computer Sciences

ABET BAND

UNIT STANDARD TYPE

PRE-2009 NQF LEVEL NQF LEVEL CREDITS

Undefined Regular Level 5 Level TBA: Pre-2009 was L5

REGISTRATION STATUS REGISTRATION START DATE

REGISTRATION END DATE

SAQA DECISION NUMBER

Reregistered 2018-07-01 2023-06-30 SAQA 06120/18

LAST DATE FOR ENROLMENT LAST DATE FOR ACHIEVEMENT

2024-06-30 2027-06-30

In all of the tables in this document, both the pre-2009 NQF Level and the NQF Level is shown. In the text (purpose statements, qualification rules, etc), any references to NQF Levels are to the pre-2009 levels unless specifically stated otherwise.

This unit standard does not replace any other unit standard and is not replaced by any other unit standard.

PURPOSE OF THE UNIT STANDARD

This unit standard is intended for people responsible for the provision of day-to-day network administration and support, including resolution of network user problems, data backup and restore, production of network performance statistics, provision of network diagnostic information, and site surveys in a local area network (LAN) environment: As fundamental knowledge of the areas covered, For those working in the Information Technology industry in the area of Network Administration, As additional knowledge for those wanting to understand the areas covered. People credited with this unit standard are able to: Maintain the performance of a local area computer network (LAN); Execute procedures on a LAN; Administer security, maintain the supply of consumables, and plan capacity for a LAN; Maintain the availability of a LAN, and Manage changes to a LAN. The performance of all outcomes is to a standard that allows for further learning in this environment.

LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING

Open. The credit value of this unit standard is calculated assuming a person has the prior knowledge and skills to apply the principles of administering local and wide area networks.

UNIT STANDARD RANGE

A "local area computer network" (LAN) is a single network of personal computers within the same area, e.g. an office or building. "Procedures" are programmes of computer operating commands.

Specific Outcomes and Assessment Criteria:

SPECIFIC OUTCOME 1

Maintain the performance of a local area network.

ASSESSMENT CRITERIA

ASSESSMENT CRITERION 1

1. Monitoring and tuning of the network ensures operation and performance meets the manufacturer`s and organisation specifications.

2. Network performance problems are resolved according to organisation specifications.

3. Accurate and up-to-date documentation is maintained of network resource utilisation.

SPECIFIC OUTCOME 2

Execute procedures on a local area computer network.

ASSESSMENT CRITERIA

1. The execution ensures that computer output is produced according to organisation specifications.

2. Procedure messages are identified during execution, and actions are taken according to organisation specifications.

3. Problems with procedures are identified, and action is taken according to organisation specifications.

4. Potential improvements to procedures are identified, and action is taken according to organisation specifications.

5. Startup and shutdown of the network are in accordance with the manufacturer`s and organisation specifications.

SPECIFIC OUTCOME 3

Administer security systems for a local area network.

ASSESSMENT CRITERIA

1. Security exposures and violations are identified, and action is taken according to organisation policies, procedures and requirements.

2. Back-ups are made according the organisations policies, procedures and specifications.

3. Access to the network is provided according to organisation policies, procedures and specifications.

SPECIFIC OUTCOME 4

Maintain the supply of consumables for a local area network.

ASSESSMENT CRITERIA

1. A forecast of the consumption of computer system consumables is justified using measurement of historical consumption and anticipated events.

2. Supply agreements are established and maintained so that the consumable supplies are available to meet demand.

3. Stocks of consumable supplies meet forecasted demand.

4. Overstocks of consumable supplies are avoided.

SPECIFIC OUTCOME 5

Plan capacity for a local area network.

ASSESSMENT CRITERIA

1. The plan includes a forecast based on documentation of current network resource utilisation, historical growth and future plans.

2. The plan includes recommendations for network changes that allow the network to meet the future capacity requirements.

3. The plan identifies and explains the feasibility of the recommendations.

4. The plan includes a comparison of actual resource usage with forecast usage according to organisation requirements.

SPECIFIC OUTCOME 6

Maintain the availability of a local area network.

ASSESSMENT CRITERIA

1. The network is available and accessible according to organisation requirements.

2. Network availability problems are resolved according to organisation specifications.

SPECIFIC OUTCOME 7

Manage changes to a local area network.

ASSESSMENT CRITERIA

1. The management ensures that a plan of a proposed change predicts the impact and risks to the organisation associated with the change.

2. The management ensures that a plan of a proposed change establishes when the change should occur to minimise the impacts and risks.

3. The management includes a contingency plan that allows the network to be restored to a status acceptable to the user in the event of problems with the change.

4. Testing establishes the success of the installation and of the changes according to user and organisation requirements.

5. The plan ensures that people affected by the change are notified to minimise disruption to their activity.

UNIT STANDARD ACCREDITATION AND MODERATION OPTIONS

The relevant Education and Training Quality Authority (ETQA) must accredit providers before they can offer programmes of education and training assessed against unit standards. An assessor, accredited by the relevant ETQA, will assess the learner`s competency. Assessment procedures will be supplied by the ETQA in alignment with NSB requirements. All assessment activities must be fair, so that all candidates have equal opportunities. Activities must be free of gender, ethnic or other bias. Assessment procedures, activities and tools must be transparent, affordable and support development within the field, sub-field and NQF. Questions and answers to determine theoretical knowledge are expected. Examination of an assessment portfolio. Reporting skills are demonstrated by effective communication, using verbal (language) and/or writing skills. Direct observation in simulated or actual work conditions. Moderation Process: Moderation of assessment will be overseen by the relevant ETQA according to the moderation guidelines in the relevant qualification and the agreed ETQA procedures Moderation procedures, activities and tools must be transparent, affordable and support development within the field, sub-field and NQF.

UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE

Familiar with Networking and Communications. The planning and management of the interaction between two or more networking systems, computers or other "intelligent" devices. E.g.: ISDN, ATM, Ethernet, TCP/IP. Familiar with Operating Infrastructure. Knowledge of the ICT infrastructure (hardware, databases, operating systems, local area networks etc) used within own organisation. Aware of Telecommunications Protocols. Rules for the inter-operation of networking components. E.g.: TCP/IP, Q931, DASS, QSIG, xDSL. Aware of Network Traffic Analysis. Methods and techniques for the capture of traffic information and the analysis of this information into its constituent elements. Familiar with Desktop Software. The use of everyday desktop software. E.g.: word processing, spreadsheets, graphics. Aware of Report Writing Techniques. Methods and techniques for writing effective reports.

UNIT STANDARD DEVELOPMENTAL OUTCOME

UNIT STANDARD LINKAGES

Critical Cross-field Outcomes (CCFO):

UNIT STANDARD CCFO IDENTIFYING

Identify and solve problems in which responses display decisions using critical and creative thinking by acquiring understanding of a problem or situation by breaking it down systematically into its component parts and identifying the relationships between these parts.

UNIT STANDARD CCFO WORKING

Work effectively with others as a member of a team, group, organisation and/or community by working co-operatively (rather than competitively) with others to achieve a common goal.

UNIT STANDARD CCFO COLLECTING

Collect, analyse, organise and critically evaluate information by identifying gaps in the available information required to understand a problem or situation and devising means of remedying such gaps.

UNIT STANDARD CCFO COMMUNICATING

Communicate effectively using visual, mathematical and/or language skills in the modes of organ and/or written presentation by establishing relationships and maintaining contacts with people from a wide variety of backgrounds.

UNIT STANDARD CCFO DEMONSTRATING

Demonstrate an understanding of the world as a set of related systems by applying quality standards to all tasks undertaken and ensuring that nothing is overlooked.

UNIT STANDARD ASSESSOR CRITERIA

REREGISTRATION HISTORY

As per the SAQA Board decision/s at that time, this unit standard was Reregistered in 2012; 2015.

UNIT STANDARD NOTES

1. Performance of all elements is to be carried out in accordance with organisation standards and procedures, unless otherwise stated. Organisation standards and procedures may cover: quality assurance, documentation, security, communication, health and safety, and personal behaviour. An example of the standards expected is the standards found in ISO 9000 Certified Organisations. 2. Performance of all elements is to be completed within the normal range of time that would be expected in a professional environment, e.g. in a commercial or government organisation. 3. Performance of all elements is to be within the normal range of cost, or cost estimate, that would be expected in a commercial environment. 4. Performance of all elements complies with the laws of South Africa, especially with regard to copyright, privacy, health and safety, and consumer rights.

onitoring and tuning of the network ensures operation and performance

meets the manufacturer`s and organisation specifications.

Design, install and evaluate Networks

The network administrator is responsible for planning, designing, installing, and evaluating

networks and workstations. Very often the administrator is also involved in researching

purchasing information on hardware and software acquisitions.

Planning and design

Planning for your network installation is one of the most important steps. Before you begin

designing the network you need to identify what your company needs are. This will help

guide you through the process and make sure you don't overlook any important details. Here

are a few important points that you should consider when designing your network.

Network design underlies the performance of your enterprise IP network. This guide offers

you a comprehensive roadmap to designing IP-based networks, from the basic principles

involved to the more complex finishing touches.

Network topology

Topology is a term that refers the shape of the network and the layout of cabling from a

bird's eye view, much as a floor plan identifies the layout of offices and hallways in a

building. See which network topology is right for your network.

Physical and logical network design

A physical layout of the network shows the physical location of and the connections between

devices participating on the network.

In such diagrams, workstations are usually represented with small computer icons, servers

with full tower cases, and switches and other similar devices are displayed as small

rectangular boxes with their RJ-45 ports in the front (sometimes, switches are displayed

without ports, depending on the angle at which we are viewing the network on the page).

Maintain the performance of a LAN Time: 90 minutes Activity: Self and Group

A logical layout shows all logical aspects of the network. This includes logical networks,

assigned IP addresses to various hosts and devices, routing tables and a lot more. In logical

diagrams, there is very little interest in the actual interfaces and physical cables, so these

details are usually omitted. Golden rules of network administration

1. If it isn't broke, don't mess with it!

2. When in doubt -- reboot.

3. Never, ever change anything late in the day.

4. Never, ever change anything on Friday.

5. Always be able to undo what you are about to do.

6. If you don't understand it, don't mess with it on a production system. Use test

systems for experimenting.

7. Dedicate a system disk devoted only to the system software. Put applications on other

drives.

8. A project is not done until it's tested by you and by end-users.

9. A project is not done until it's documented.

10. All projects take twice as long as you plan.

11. Use default settings whenever possible.

12. Do not roll out new software without training end users. Roll out an employee's new

application immediately after they have received training to reinforce what they have learned.

13. If you're fighting fires all the time, find the source.

14. Avoid poor decisions from above.

15. Backup, backup, backup.

etwork performance problems are resolved according to organisation

specifications.

Backup management

The network administrator is responsible for network backups as well as testing

backup and disaster recovery processes. This is crucial for recovery from power or hardware

failure, data and/or network problems, and physical disasters.

Backup guidelines:

In many ways, backups are the heart of any design of critical systems. Handled properly,

they represent the last line of defense against just about any catastrophe. Even if your

building or your entire city is wiped out, your business can be restored on other computers

from properly generated and protected backup tapes. But there are several "if" conditions

that must be satisfied for everything to work out properly and data to be recoverable.

There are a number of basic backup guidelines. By keeping them in mind as you design your

backup environment, you will make the best advantage of your backups, and they will serve

you best when you need them:

1. Mirroring does not replace backups.

2. The most common use of restores isn't after a catastrophe.

3. Regularly test your ability to restore.

4. Keep those tape heads clean.

5. Beware of dirty tapes.

6. Pay attention to Mean Time Between Failure (MTBF) numbers for tapes.

7. Tapes decompose over time.

8. Make two copies of critical tapes.

9. Make sure you can still read old media.

Backup management headaches

The amount of data that companies are producing is growing exponentially. The sheer

quantity of data doesn't make it any less important to the company. So every bit needs to be

backed up in case of an accidental deletion, a hardware failure or, as we have been reminded

recently, an actual disaster. Everyone knows the data needs to be preserved, but how does

an network administrator go about doing that without devoting all his time to backup

management?

It's definitely an issue that hasn't gone unnoticed among the many backup software

companies. Backup software is a multimillion-dollar industry, and wading through the

vendor rhetoric can be a challenge in and of itself. Here we take a look at the biggest backup

management headaches and challenges for network administrators:

1. Shrinking backup window.

2. Inability to force an enterprise-wide centralized backup policy.

3. Inability to backup desktops and laptops confidently.

4. Network bandwidth limitations.

5. Rapidly growing data, and finding a place for it all.

6. Tape management for recovery.

7. Restoring quickly.

8. Difficulty of backing up complex, heterogeneous environments.

9. Remote management.

10. Tape security.

Disaster recovery plan

1. It is critical that you obtain and maintain senior executive support for disaster

recovery (DR).

2. Determine which senior executive(s) will have overall responsibility for disaster recover

and have this person appoint a DR coordinator.

3. Appoint a disaster recover team leader for each operational unit.

4. Identify functions, process and systems. Determine critical systems, applications and

business processes that must continue through disaster recover.

5. Prepare impact analysis on interruptions on critical systems.

6. Review physical security.

7. Review backup systems and data security.

8. Review policies on personnel termination and transfer.

9. Identify systems supporting mission-critical functions.

10. Identify vulnerabilities (e.g. physical attacks, floods, fire, earthquakes, etc.)

11. Access probability of system failure or disruption.

12. Prepare risk and security analysis.

13. Develop a strategic outline for recovery.

14. Detail all the steps in your workflow for each critical business function.

15. Review onsite and offsite backup and recovery procedures.

16. Select, equip, duplicate and prepare staff for an alternate facility.

17. Develop recovery plan.

18. Test the plan. Schedule to update and maintain the plan on a routine basis.

Managing network traffic during backups

Backup and verification operations can create significant increases in network traffic. This

can lead to reduced performance of your servers and all of the segments of the network

involved in the backup.

One solution to the problem of course is scheduling backups at a time when network usage

is low, like before or after hours. Since this may not always be possible, you can perform

backups in smaller incremental steps during normal hours.

ccurate and up-to-date documentation is maintained of network

resource utilisation.

Network documentation and auditing

The first step toward administering a network is to have accurate and complete

documentation of the network. Documenting a network will reduce administration time for

issues such as updates, user problems and disaster recovery. There are four basic parts of a

network that should be documented:

LAN Software

LAN Hardware

Network Diagram

User Names (ID numbers) and network numbers.

All documents should be kept in a secured location. Make sure that you have a policy in

place and a person assigned to the responsibility of keeping all documentation up to date

and accurate.

Documenting your network

1. Obtain or construct a building diagram/floor plan.

2. Obtain or construct a physical network diagram.

3. Obtain or construct a logical network diagram. (Software packages can research and

record all hardware information.)

4. Hardware information should include make, serial numbers, and numbers of ports as

well as MAC and NIC numbers.

5. Research and record all configuration, protocol and DNS information.

6. Print copies of configurations files; keep those copies on tape for removable disk.

7. Document specific software configurations.

8. Research and record all corporate contact and vendor information.

9. Product and maintain device log sheets for all applicable network devices.

10. Product and maintain a network cabling labelling scheme. Do not base the labelling

on names of users.

11. Product and maintain procedure documentation.

12. Product and maintain computer and network acceptable use policies.

13. Product and maintain computer and network security policies.

14. Product and maintain a disaster recovery plan.

15. Schedule to update and maintain these items on a regular basis.

16. Never share these documents with unauthorized individuals -- ever!

Network diagrams

Documenting your network doesn't exactly sound like the most exciting way to spend your

time, does it? It involves creating a diagram, usually with a documentation tool such as Visio

or LanFlow, that illustrates how your servers, routers and switches are connected, either

logically or physically. However, comprehensive network documentation can be of vital

importance. In addition to serving as a network blueprint, it can also help you remember

what you did to your network, and just as importantly, why. This can make maintaining

your network and troubleshooting problems a much easier and smoother process.

Network cabling documentation

Picture these scenarios: A quick and simple network change turns into disaster when instead

of disconnecting the correct cable, you actually disconnect the cable to a critical server. A

security audit requires you to document the physical path location of cables carrying

sensitive information and who has access to those cables. But your documentation of cable

location and the identity of all the endpoints to which they are connected is out of date.

Network auditing

Network auditing may be a time-consuming chore that you probably don't have time for. It's

more than likely, however, that someone has already gone to the trouble and is scanning

your network for weak points to attack. It could be someone within your organisation;

statistics show that more than 60% of computer crimes originate inside the enterprise. So

remember that the best defence is a good offence, and you cannot raise a good defence

unless you know where your network is weak.

Before a network services audit can begin, a network inventory must be conducted. An

inventory includes collecting host identification information, such as IP address, network

interface hardware (NIC) address and DNS entries, for all network nodes. While some of this

information will be on hand in most environments, often it will have errors. In most cases,

NIC information and MAC addresses will not be recorded.

Even if you think you have the information, it's a good idea to conduct the inventory and

verify the information as a first step to an audit. This allows you to build a complete picture

of the environment and, as an additional benefit, will reveal inconsistencies that should be

cleaned up.

Performing a network audit

1. Use outside vendors to conduct and audit. This will ensure that there is no

favouritism or politics in the results, and provide credibility with senior management. Ensure

the vendor or contractor you use covers the items listed below as a minimum. Find out who

will be conducting the audit and review resume and references from past audited companies.

Ensure goals of the audit are adhered to.

2. It is highly recommended that you perform an internal audit prior to outside audit so

you can compare results.

3. Establish and document baseline performance of all network components.

4. Review, document and analyse controls over Internet, intranet and network resources.

5. Review and document all network connections, client/server, LAN, WAN, etc.

6. Review and document controls over network operations and management, load/traffic

management and problem reporting and resolution.

7. Review and assess network segmentation and identify and audit any internal firewalls.

8. Review and assess a single point of failure analysis. How is your network affected by

critical equipment? Do you have backups installed and ready?

9. Prepare a risk assessment and develop and implement a risk mitigation plan.

10. Review and document all software licenses required/possessed for all locations.

11. Verify and record all installed software. Remove all unauthorized software and secure

hardware and software to prevent future downloads or installations.

Network management and troubleshooting

It is the network administrator's responsibility to make sure the network is working properly

and efficiently. You'll also provide maintenance and support for your end-users equipment,

regardless if it's on site or remote.

Golden rules of network administration

1. If it isn't broke, don't mess with it!

2. When in doubt -- reboot.

3. Never, ever change anything late in the day.

4. Never, ever change anything on Friday.

5. Always be able to undo what you are about to do.

6. If you don't understand it, don't mess with it on a production system. Use test

systems for experimenting.

7. Dedicate a system disk devoted only to the system software. Put applications on other

drives.

8. A project us not done until it's tested by you and by end-users.

9. A project is not done until it's documented.

10. All projects take twice as long as you plan.

11. Use default settings whenever possible.

12. Do not roll out new software without training end users. Roll out an employee's new

application immediately after they have received training to reinforce what they have learned.

13. If you're fighting fires all the time, find the source.

14. Avoid poor decisions from above.

15. Backup, backup, backup.

The task of maintaining an operational network delivering predictable, reliable services to

meet enterprise needs has always been and remains the day-to-day task of legions of

network management and operations professionals. The task becomes more difficult and

more critical to business success as a result of escalating demands for better performance,

increased reliability and dynamic adaptability.

These demands result from a proliferation of more complex, more distributed, and more

dynamic business services. To meet customer demands, services are exhibiting a growing

addiction to network-based solutions (for e.g., VoIP) and an emerging interest in

sophisticated, bandwidth-intensive applications such as IP Multimedia Services.

Desktop management

Desktop management is one of the big headaches of the IT world. Systems administrators

face a number of challenges in controlling the corporate desktop. Tracking an entire

company's PCs, which can range into the thousands, isn't an easy task.

Making sure every employee has a functional desktop and coordinating rollouts of software

updates and operating system migrations across those PCs is no picnic either. But following

some common-sense principles can make desktop management easier for all parties

involved.

Spyware

It could happen to you. Your PCs could be infested with spyware or adware. The key is to

know where to look and what to record as spyware digs through your hard disk, memory and

Windows registry. By following a regular process you can keep spyware at bay

Network security and viruses

The administrator often acts as the security officer of the network. It is your responsibility to

investigate and resolve unsuccessful login attempts, intruder detection lockouts,

compromised passwords, viruses, spam and security policies

Perform a security audit

1. Use outside vendors to conduct and audit. This will ensure that there is no

favouritism or politics in the results, and provide credibility with senior management. Ensure

the vendor or contractor you use covers the items listed below as a minimum. Find out who

will be conducting the audit and review resume and references from past audited companies.

Ensure goals of the audit are adhered to.

2. Assess physical security: Video monitoring, data and portable media handling, paper

shredding methods and policies, physical layout and location of data centre, security of LAN

closets, cleaning crew access, key and access controls and logging and challenge the

procedures.

3. Assess network security: Proper segmentation of LAN and WAN, proper passwords,

limited use of protocols -- only those necessary are installed, IDS systems within the

organization, firewalls, redundancy and failover or clustering of servers, routers and

switches, restricted us of dial-up anywhere in your organization – including prohibition of

telnet or other unnecessary protocols.

4. Application security: Encryption, default accounts renamed, deleted, changed

passwords, all software and Web/email servers hardened, patched, updated and secured.

5. Policy and procedures: Acceptable use policies, security incident handling procedures,

incident escalations, remote access policy, firewall management policy, disaster recover

policy. Security awareness training for all employees is a never-ending process.

Security policies

A well-designed security policy is a powerful tool in your network security arsenal. Using

built-in tools found in Windows, you can create and enforce your own custom security policy

for all of the systems in your network

he execution ensures that computer output is produced according to

organisation specifications

Count the number of computers you need to hardwire. When setting up a LAN,

you'll need to know how many computers will be connecting to the network via

Ethernet. This will determine the number of ports you'll need. If you have four or less

computers that you need to hardwire, you'll just need a router. If you have more than four,

you'll likely need to get a switch to extend the number of ports available on your router.

Decide if you want to create a wireless network. If you want to allow devices to connect

wirelessly, you'll need a router that can broadcast a wireless network. Most routers you'll

find at the store or online have wireless capabilities. Network switches do not allow wireless

devices to connect, and can only be used for hardwired LANs or to extend the number of

ports available to the router.

Determine if you want all network devices to have internet access. If you want all of the

connected devices to have access to the internet, you'll need a router to handle the

connections. If you don't need the devices to have a network connection, you can just use a

network switch.

Measure the distances for all hardwired devices. This isn't much of an issue in most homes,

but network cables cannot run longer than 100m. If you have to run cable farther than this,

you'll need switches in between. Consider your future needs. If you're filling all of the ports

on your hardware, consider future-proofing to allow for more devices in the future.

Setting Up a Basic LAN

Gather your network hardware. To create a LAN, you'll need a router or switch, which will

act as the hub of your network. These devices route information to the correct computers.

A router will automatically handle assigning IP addresses to each device on the network, and

is necessary if you intend to share your internet connection with all the connected devices. It

is highly recommended that you build your network with a router, even if you're not sharing

an internet connection.

Execute procedures on a LAN Time: 90 minutes Activity: Self and Group

A network switch is like a simpler version of a router. It will allow connected devices to talk

to each other, but will not automatically assign IP addresses and will not share an internet

connection. Switches are best used to expand the number of LAN ports available on the

network, as they can be connected to the router.

Set up your router. You don't need to do much to set up a router for a basic LAN. Just plug it

into a power source, preferably close to your modem if you plan on sharing the internet

connection through it.

Connect your modem to your router (if necessary). If you're sharing the internet connection

from your modem, connect the modem to the WAN/INTERNET port on the router. This is

usually a different colour from the other ports. Connect your switch to your router (if

necessary). If you're using a switch to expand the number of ports available on the router,

plug an Ethernet cable into any LAN port on the router and any LAN port on the switch. This

will expand the network to the rest of the LAN ports on the switch.

Connect your computers to open LAN ports. Use Ethernet cables to connect each computer

to an open LAN port on your router or switch. It doesn't matter what order the ports are

connected in. Ethernet cables cannot reliably transfer data at lengths larger than 100m.

Setup one PC as a DHCP server if you're just using a switch. If you're only using a switch as

your network hub, setting up one computer as a DHCP (Dynamic Host Configuration

Protocol) server will allow all of the connected computers to easily obtain IP addresses.

You can quickly create a DHCP server on one of your computers by installing a third-party

utility.

The rest of the computers on the network will obtain IP addresses automatically once the

server is running, as long as they are set to do so. Verify the network connection on each

computer. After each computer obtains an IP address, they'll be able to talk to each other on

the network. If you're using a router to share your internet connection, each computer will be

able to access the internet.

Set up file and printer sharing. Once your network is up, you won't see anything on other

computers unless that computer has shared files. You can designate files, folders, drives,

printers, and other devices as shared so that anyone on the network, or just specific users,

can access them.

rocedure messages are identified during execution, and actions are

taken according to organisation specifications.

Communication over the network

The Elements of Communication

Communication begins with a message, or information, that must be sent from one

individual or device to another. People exchange ideas using many different communication

methods. All of these methods have three elements in common. The first of these elements is

the message source, or sender. Message sources are people, or electronic devices, that need

to send a message to other individuals or devices.

The second element of communication is the destination, or receiver, of the message. The

destination receives the message and interprets it. A third element, called a channel, consists

of the media that provides the pathway over which the message can travel from source to

destination. Consider, for example, the desire to communicate using words, pictures, and

sounds. Each of these messages can be sent across a data or information network by first

converting them into binary digits, or bits.

These bits are then encoded into a signal that can be transmitted over the appropriate

medium. In computer networks, the media is usually a type of cable, or a wireless

transmission. The term network in this course will refer to data or information networks

capable of carrying many different types of communications, including traditional computer

data, interactive voice, video, and entertainment products.

Communicating the Messages

In theory, a single communication, such as a music video or an e-mail message, could be

sent across a network from a source to a destination as one massive continuous stream of

bits. If messages were actually transmitted in this manner, it would mean that no other

device would be able to send or receive messages on the same network while this data

transfer was in progress.

These large streams of data would result in significant delays. Further, if a link in the

interconnected network infrastructure failed during the transmission, the complete message

would be lost and have to be retransmitted in full. A better approach is to divide the data

into smaller, more manageable pieces to send over the network. This division of the data

stream into smaller pieces is called segmentation.

Segmenting messages has two primary benefits. First, by sending smaller individual pieces

from source to destination, many different conversations can be interleaved on the network.

The process used to interleave the pieces of separate conversations together on the network

is called multiplexing. Second, segmentation can increase the reliability of network

communications.

The separate pieces of each message need not travel the same pathway across the network

from source to destination. If a particular path becomes congested with data traffic or fails,

individual pieces of the message can still be directed to the destination using alternate

pathways. If part of the message fails to make it to the destination, only the missing parts

need to be retransmitted.

The downside to using segmentation and multiplexing to transmit messages across a

network is the level of complexity that is added to the process. Imagine if you had to send a

100-page letter, but each envelope would only hold one page. The process of addressing,

labelling, sending, receiving, and opening the entire hundred envelopes would be time-

consuming for both the sender and the recipient.

In network communications, each segment of the message must go through a similar process

to ensure that it gets to the correct destination and can be reassembled into the content of

the original message. Various types of devices throughout the network participate in

ensuring that the pieces of the message arrive reliably at their destination.

Components of the Network

The path that a message takes from source to destination can be as simple as a single cable

connecting one computer to another or as complex as a network that literally spans the

globe. This network infrastructure is the platform that supports our human network. It

provides the stable and reliable channel over which our communications can occur. Devices

and media are the physical elements or hardware of the network.

Hardware is often the visible components of the network platform such as a laptop, a PC, a

switch, or the cabling used to connect the devices. Occasionally, some components may not

be so visible. In the case of wireless media, messages are transmitted through the air using

invisible radio frequency or infrared waves. Services and processes are the communication

programs, called software, that run on the networked devices. A network service provides

information in response to a request.

Services include many of the common network applications people use every day, like e-mail

hosting services and web hosting services. Processes provide the functionality that directs

and moves the messages through the network. Processes are less obvious to us but are

critical to the operation of networks.

End Devices and their Role on the Network

The network devices that people are most familiar with are called end devices. These devices

form the interface between the human network and the underlying communication network.

Some examples of end devices are:

Computers (work stations, laptops, file servers, web servers)

Network printers

VoIP phones

Security cameras

Mobile handheld devices (such as wireless barcode scanners, PDAs)

In the context of a network, end devices are referred to as hosts. A host device is either the

source or destination of a message transmitted over the network. In order to distinguish one

host from another, each host on a network is identified by an address. When a host initiates

communication, it uses the address of the destination host to specify where the message

should be sent. In modern networks, a host can act as a client, a server, or both.

Software installed on the host determines which role it plays on the network. Servers are

hosts that have software installed that enables them to provide information and services, like

e-mail or web pages, to other hosts on the network. Clients are hosts that have software

installed that enables them to request and display the information obtained from the server.

Intermediary Devices and their Role on the Network

In addition to the end devices that people are familiar with, networks rely on intermediary

devices to provide connectivity and to work behind the scenes to ensure that data flows

across the network. These devices connect the individual hosts to the network and can

connect multiple individual networks to form an internetwork. Examples of intermediary

network devices are:

Network Access Devices (Hubs, switches, and wireless access points)

Internetworking Devices (routers)

Communication Servers and Modems

Security Devices (firewalls)

The management of data as it flows through the network is also a role of the intermediary

devices. These devices use destination host address, in conjunction with information about

the network interconnections, to determine the path that messages should take through the

network. Processes running on the intermediary network devices perform these functions:

Regenerate and retransmit data signals

Maintain information about what pathways exist through the network and

internetwork

Notify other devices of errors and communication failures

Direct data along alternate pathways when there is a link failure

Classify and direct messages according to QoS priorities

Permit or deny the flow of data, based on security settings

Network Media

Communication across a network is carried on a medium. The medium provides the channel

over which the message travels from source to destination. Modern networks primarily use

three types of media to interconnect devices and to provide the pathway over which data can

be transmitted.

These media are:

Metallic wires within cables

Glass or plastic fibers (fiber optic cable)

Wireless transmission

The signal encoding that must occur for the message to be transmitted is different for each

media type. On metallic wires, the data is encoded into electrical impulses that match

specific patterns. Fiber optic transmissions rely on pulses of light, within either infrared or

visible light ranges.

In wireless transmission, patterns of electromagnetic waves depict the various bit values.

Different types of network media have different features and benefits. Not all network media

has the same characteristics and is appropriate for the same purpose. Criteria for choosing a

network media are:

The distance the media can successfully carry a signal.

The environment in which the media is to be installed.

The amount of data and the speed at which it must be transmitted.

The cost of the media and installation

LANs, WANs, and Internetworks

Local Area Networks

Networks infrastructures can vary greatly in terms of:

The size of the area covered

The number of users connected

The number and types of services available

An individual network usually spans a single geographical area, providing services and

applications to people within a common organizational structure, such as a single business,

campus or region. This type of network is called a Local Area Network. A LAN is usually

administered by a single organization. The administrative control that governs the security

and access control policies are enforced on the network level.

Wide Area Networks

When a company or organization has locations that are separated by large geographical

distances, it may be necessary to use a telecommunications service provider (TSP) to

interconnect the LANs at the different locations. Telecommunications service providers

operate large regional networks that can span long distances. Traditionally, TSPs transported

voice and data communications on separate networks.

Increasingly, these providers are offering converged information network services to their

subscribers. Individual organizations usually lease connections through a

telecommunications service provider network. These networks that connect LANs in

geographically separated locations are referred to as Wide Area Networks (WANs). Although

the organization maintains all of the policies and administration of the LANs at both ends of

the connection, the policies within the communications service provider network are

controlled by the TSP.

WANs use specifically designed network devices to make the interconnections between LANs.

Because of the importance of these devices to the network, configuring, installing and

maintaining these devices are skills that are integral to the function of an organization's

network. LANs and WANs are very useful to individual organizations. They connect the users

within the organization. They allow many forms of communication including exchange e-

mails, corporate training, and other resource sharing.

roblems with procedures are identified, and action is taken according to

organisation specifications

A faulty Wi-Fi connection doesn’t have to ruin your day. There are plenty of ways

you can restore a lost internet connection. Follow these network troubleshooting

tips and you’ll be up and running in no time.

1. Check Your Settings

First, check your Wi-Fi settings. Go to Settings > Network & Internet > Wi-Fi. Switch Wi-Fi to

the On position. Phones and tablets also have settings that turn Wi-Fi on and off. Make sure

that it is turned on so you can connect to the network. You also want to check if Airplane

Mode is turned on.

2. Check Your Access Points

Check your WAN (wide area network) and LAN (local area network) connections. In layman’s

terms, these are the Ethernet cables that go to and from your router. If you suspect that the

cables are the culprit, try swapping them out with new ones.

3. Go Around Obstacles

Walls, furniture, and other obstructions can be the reason why you’re unable to go online.

Moving closer to the router can re-establish the connection. If moving closer to the router

does not solve the issue, then at least we can remove it from the list of suspects.

4. Restart the Router

Sometimes restarting the router can help fix connectivity issues. This is even truer in cases

where the router has not been turned off in a while. A quick restart can jolt the router back

into working like it used to. If that doesn’t work, you might also consider resetting the router.

But only do so if you’re okay with it being restored to its factory settings. You will have to

reconfigure everything including the SSID and password.

5. Check the Wi-Fi Name and Password

Check the network name (otherwise known as SSID) and password of the network

connection. If you’re used to connecting automatically when in range of a router but are no

longer able to, changes may have been made to the network while you’re away.

It could be as simple as administrators updating the password or the SSID could have been

changed to a different one.

6. Check DHCP Settings

Routers are usually set up as DHCP servers. This setting lets computers join a network

automatically. With DHCP turned on, users will no longer have to mess with IP Address and

DNS Server settings manually. To edit your DHCP settings, go to Windows Settings >

Network & Internet > Wi-Fi. Under Wi-Fi, click Manage Known Networks. Select a network

and click Properties. Under IP Settings, click Edit. From the drop-down menu, select

Automatic (DHCP). Note: Selecting Manual will let you set your DNS Server Address and IP

Address settings manually.

7. Update Windows

Your network problems could be caused by your system. If that is the case, Windows could

have possibly released a fix. Try updating your Windows machine to the latest release.

Go to Windows Settings > Update & Security > Windows Update. Click Check for Updates. If

there are updates available, Windows will download and install them.

8. Open Windows Network Diagnostics

Windows has a tool called Windows Network Diagnostics that lets users troubleshoot

connection issues. Go to Windows Settings > Network & Internet > Status. Under Change

Your Network Settings, click Network Troubleshooter. Windows Network Diagnostics will run

a couple of tests to see what’s possibly causing your Wi-Fi issues. Windows will let you know

if it does not find any issue. Otherwise, you will be given a list of possible actions to take to

resolve the problem. This tool, or a version of it, should be available in Windows 7 to

Windows 10.

otential improvements to procedures are identified, and action is taken

according to organisation specifications.

When designing a new computer network, whether for five people or 500, it's

important to weigh the needs and desires of those who will be using the network

with the budget of those who will be paying for it. Some important things to consider that

may not be on anyone's wish list include balancing security issues with the desire for easy

access to information; building redundancy into the network in anticipation of breakdowns;

and standardizing hardware and software to keep maintenance costs in check. In case

something terrible happens, a disaster recovery plan should be in place. In case things go

well for the organization, room for future growth should be built into the network design.

Important things to consider include balancing security issues with the desire for easy

access to information; building redundancy into the network in anticipation of breakdowns;

and standardizing hardware and software to keep maintenance costs in check.

Connectivity and Security

Network connectivity today means more than Ethernet cables and wireless access points.

People today are more connected while mobile than ever before and many of them want

access to company email and data while they are out of the office. Balancing those needs

while maintaining security is a challenge that needs to be addressed in the design phase of

any network.

This includes where data is stored, either in-house or offsite with cloud-based solutions,

what types of information should be accessible, who should be able to access it, and which

types of devices should be included. Firewalls and access servers need to be secure without

slowing down operations.

Redundancy and Backing Up

Redundancy means having backup devices in place for any mission-critical components in

the network. Even small organizations should consider using two servers. Two identical

servers, for example, can be configured with fail-safes so that one will take over if the other

fails or requires maintenance. A good rule of thumb is to have redundant components and

services in place for any part of a network that cannot be down for more than an hour.

If an organization hosts it own Web servers, or cannot be without Internet connectivity, a

second connection should be in place. Having an extra switch, wireless router, and a spare

laptop onsite is a good practice for ensuring that downtime is kept to a minimum.

Standardization of Hardware and Software

Standardization of the hardware and software used in a network is important for ensuring

the network runs smoothly. It also reduces costs associated with maintenance, updates and

repairs. Conducting a full audit of the current computer systems, software and peripherals

will help to determine which should be standardized.

A CEO or director may require special consideration, but if 90 percent of the employees use

the same notebooks, with the same word processing and email programs, a software or

hardware patch across the organization can be conducted much less expensively than if

everyone used a different computer model with different software installed on each.

Disaster Recovery Plan

A detailed disaster recovery plan should be a part of any network design. This includes, but

is not limited to, provisions for back-up power and what procedures should be followed if the

network or server crashes. It should also include when data is backed up, how it is backed

up and where copies of the data are stored. A comprehensive disaster recovery plan includes

office disasters, building disasters, and metropolitan-wide disasters.

In most cases, important data should be backed up daily. Many organizations do a full

weekly backup, with daily incremental backups that copy any files that have been modified

since the last weekly backup. Backup files should be stored in a secure location off-site in

the event of a building disaster, such as a fire.

Future Growth of the Organization

While it is not always possible to anticipate how large an organization may be five years in

the future, some allowances for future growth must be built into the network design. For

example, Microsoft Small Business Server can be an excellent choice for many small

organizations.

However, if your office already has sixty employees, Small Business Server could soon be a

wasted investment, as it has a limit of only 75 users. Network design should factor in at least

20 percent growth per year, including everything from switch ports to data backup systems.

tartup and shutdown of the network are in accordance with the

manufacturer`s and organisation specifications.

Working with startup, shutdown, logon, and logoff scripts using the Local Group

Policy Editor. This topic describes how to use the Local Group Policy Editor (gpedit)

to manage four types of event-driven scripting files.

Introduction

Group Policy allows you to associate one or more scripting files with four triggered events:

Computer startup

Computer shutdown

User logon

User logoff

You can use Windows PowerShell scripts, or author scripts in any other language supported

by the client computer. Windows Script Host (WSH) supported languages are also used,

including VBScript and Jscript.

Additional considerations

For more information about scripting, see the Group Policy Script Center

Local Group Policy Editor and the Resultant Set of Policy snap-in are available in Windows

Server 2008 R2 and Windows 7 Professional, Windows 7 Ultimate, and Windows 7

Enterprise.

How to assign computer startup scripts

To assign computer startup scripts

Open the Local Group Policy Editor.

In the console tree, click Scripts (Startup/Shutdown). The path is Computer

Configuration\Windows Settings\Scripts (Startup/Shutdown).

In the results pane, double-click Startup.

In the Startup Properties dialog box, click Add.

In the Add a Script dialog box, do the following:

In the Script Name box, type the path to the script, or click Browse to search for the

script file in the Netlogon shared folder on the domain controller.

In the Script Parameters box, type any parameters that you want, the same way as

you would type them on the command line. For example, if your script includes

parameters called //logo (display banner) and //I (interactive mode), type //logo //I.

In the Startup Properties dialog box, specify the options that you want:

Startup Scripts for <Group Policy object>: Lists all the scripts that currently are

assigned to the selected Group Policy object (GPO). If you assign multiple scripts, the

scripts are processed in the order that you specify. To move a script up in the list,

click it and then click Up. To move a script down in the list, click it and then click

Add: Opens the Add a Script dialog box, where you can specify any additional scripts

to use.

Edit: Opens the Edit Script dialog box, where you can modify script information, such

as name and parameters.

Remove: Removes the selected script from the Startup Scripts list.

Show Files: Displays the script files that are stored in the selected GPO.

Additional considerations

To complete this procedure, you must have Edit setting permission to edit a GPO. By default,

members of the Domain Administrators security group, the Enterprise Administrators

security group, or the Group Policy Creator Owners security group have Edit setting

permission to edit a GPO.

Startup scripts are run under the Local System account, and they have the full rights that

are associated with being able to run under the Local System account. Beginning in Windows

Vista, startup scripts are run asynchronously, by default. This is a different behaviour from

earlier operating systems. Setting startup scripts to run synchronously may cause the boot

process to run slowly.

In Windows 7 and Windows Vista, startup scripts that are run asynchronously will not be

visible. Enabling the Run Startup Scripts Visible policy setting will have no effect when

running startup scripts asynchronously. Local Group Policy Editor and the Resultant Set of

Policy snap-in are available in Windows Server 2008 R2 and Windows 7 Professional,

Windows 7 Ultimate, and Windows 7 Enterprise.

How to assign computer shutdown scripts

To assign computer shutdown scripts

Open the Local Group Policy Editor.

In the console tree, click Scripts (Startup/Shutdown). The path is Computer

Configuration\Windows Settings\Scripts (Startup/Shutdown).

In the results pane, double-click Shutdown.

In the Shutdown Properties dialog box, click Add.

In the Add a Script dialog box, do the following:

In Script Name, type the path to the script, or click Browse to search for the script file

in the Netlogon shared folder on the domain controller.

In Script Parameters, type any parameters that you want, the same way as you would

type them on the command line. For example, if your script includes parameters

called //logo (display banner) and //I (interactive mode), type //logo //I.

In the Shutdown Properties dialog box, specify the options that you want:

Shutdown Scripts for <Group Policy object>: Lists all the scripts that are currently

assigned to the selected Group Policy object (GPO). If you assign multiple scripts, the

scripts are processed in the order that you specify. To move a script up in the list,

click it and then click Up. To move a script down in the list, click it and then click

Add: Opens the Add a Script dialog box, where you can specify any additional scripts

to use.

Edit: Opens the Edit Script dialog box, where you can modify script information, such

as name and parameters.

Remove: Removes the selected script from the Shutdown Scripts list.

Show Files: Displays the script files that are stored in the selected GPO

ecurity exposures and violations are identified, and action is taken according

to organisation policies, procedures and requirements.

Before you can make your LAN available, you need to be able to install it. The following steps

will take you through the installation, one step at a time.

Overview

All of the computers and devices on your network should have Internet addresses between

192.168.x.2 and 192.168.x.254. When you are configuring your network, you have two

choices:

Manually set the IP address to a specific number (static IP) or

Set the client IP address (via the DHCP server).

If you configure devices with static IP

addresses, make sure you only use

an address between 192.168.1.2 -

192.168.1.99. You should use your

Internet Service Provider's DNS

servers.

Network Settings

Step 1 - Control Panel

Click on the Start button,

then follow the menu to

Settings > Control Panel

Double-click on the Network

Connections

Right click on Local Area

Connection and go to Properties

Step 2 - Select IP Properties

Administer security systems for a LAN Time: 120 minutes Activity: Self and Group

Select TCP/IP and click on the Properties button

Step 3 - IP Address

On the IP Address tab, you can select Obtain an IP address automatically it will

automatically assign an IP address for you. Alternatively, you can choose Specify an IP

address (as shown in the screenshot). Make sure you pick an address between 192.168.1.2

to 192.168.1.99. The subnet mask is always 255.255.255.0.

Step 4 - DNS Settings

If you decided to let the Windows assign your IP address automatically, then you can select

Disable DNS. Windows will automatically configure these settings. If you decided to specify

your IP address, then you will need to

add 192.168.1.1 to the DNS Server

Search Order list. You should also add a

host name and then add "lan" as the

domain. You should add the DNS servers

given by your Internet service provider

Network & Its

availability

Make sure that you

the amount of

points available to

the needs of your

organisation. There

is no use for

employees if these

points are not available to them, to conduct their duties on.

A speed check should be done on the individual nodes from time to time to ensure that they

are maintaining the correct speed, and to ensure that the employees using them are not

slowed down, due to slower networking speeds. As per the agreement with your internet

service provider (ISP), your connection should be strong enough and be able to handle the

traffic it is supposed to. Alternate arrangements will have to be made it these speeds and

traffic cannot be handled.

ack-ups are made according the organisations policies, procedures and

specifications.

Forecasting and Ensuring change

With the constant upgrading of both hard- and software in the organisation, it is advisable

that there are continuous upgrades done on the systems to ensure that you are able to

provide the users of the computers with the fastest possible speeds and the highest levels of

security. Changes in the networks must be done in a systematic manner to ensure that

minimal time is lost by employees held up, while their systems are being upgraded.

The best manner to conduct such upgrades is after normal office hours, where all the

systems in one department is changed and set up correctly. The systems should then be

checked one at a time to ensure that they are properly working and functioning, as they were

before. Keeping in mind that the mainframe of the organisation itself will not be changed, but

merely the network, there will be no significant changes. Therefore the data on the

computers and the network will not be affected, but it is advisable to make a back-up in any

With the formal back-

up being done, if

there are any

problems which

occur, then there will

be a form of back-up

for the company

which they can fall

back on, which

means that there will

be no information

loss on the side of the

organisation.

With the change of the network, the entire process should be planned in phases to ensure

that there is minimal disruption to the employees with this change.

Doing it department by department will also assist in the eradication of problems, if there are

any. One should start the upgrade with the department using the most traffic on the network

to ensure that their systems are always up to date and provide them with the required

speeds.

Contingency plans for the disruption of the employees must be worked, if the change does

not happen as effortlessly as what is anticipated. Any problems with change solutions should

include the fall-back plan where the old version is used to make the necessary changes to

the new system and in that way ensure that there are no disruptions to production.

Once the new network has been installed, it is required that the network be tested to ensure

that there are no problems with it. This should be done by testing that all the workstations

have their connectivity to both the internet as well as the server and by testing the speed

that the network delivers to its individual users.

Network software testing comprises of two parts:

Sender Generates TCP and UDP traffic in 'unitary' mode where each connection is

configured separately or 'automatic' mode where all connections are generated as a

whole.

Sender Unitary Mode

The user chooses protocol (TCP or UDP) and data source with mathematical laws

(Pareto, Uniform, Exponential), file or packet generator with configurable contents.

Inter-packet delay and packet size may be selected. Received data and RTT (round

trip time) information may be saved.

Sender Automatic Mode

In this mode, the user may choose the number of connections to activate plus

starting time, the volume of transmitted data and packet size of enabled

connections.

Receiver Receives IP connections and may be disabled or configured to echo, absorb or file

absorb.

Testing network cable

ACR - The first thing to understand about testing

data cables is the ACR. This stands for

attenuation to crosstalk ratio. The pink area in

the graph is the attenuation. Attenuation is the

reduction in signal strength over the length of the

cable and frequency range. The blue area is the

crosstalk. Crosstalk is the external noise that is

introduced into the cable. So, if the two areas

meet, the data signal will be lost because the

crosstalk noise will be at the same level as the

attenuated signal. ACR is the most important

result when testing a link because it represents the overall performance of the cable. The

question becomes "What causes the signal to attenuate and where does the crosstalk come

from?"

Length

The length of a cable is one of the more obvious causes

of attenuation because the longer it is, the more

resistance it has, and therefore less of the signal will

get through. To measure the length, a cable tester uses

Time Domain Reflectometry (TDR). A pulse is sent

down the cable and when it reaches the far end it

reflects back.

By measuring the time it takes to travel down the

cable and back again, the tester can determine how

long the cable is. To do this, the tester also needs to

know how fast the pulsed signal is travelling. This is

called the Nominal Velocity of Propagation (NVP) and is

expressed as a percentage of the speed of light.

The NVP is usually somewhere between 60% and 90%

of the speed of light, with most Cat 5E cables being

around 70%. Due to the twists in the cable, the

measured length will be greater than the physical length, so if a run looks like it might be

over 80m it would be wise to check it before it is tied up and terminated.

Attenuation

This is the decrease in signal strength (expressed as negative dB) from one end of a cable to

the other. The main causes of attenuation are impedance, temperature, skin effect and

dielectric loss.

Impedance

Impedance is the combination of resistance, inductance and capacitance in a cable. It is

measured in Ohms and opposes the flow of current.

Skin effect

Skin effect is phenomena which happen at high frequencies where the signal tries to escape

from the confines of the copper and into the air. The signal travels along the outer 'skin' of

the copper which effectively reduces the cross sectional area of the cable and therefore

increases its resistance.

Wire map

This test is to ensure that the two ends have been terminated pin for pin, i.e. that pin 1 at

the patch panel goes to pin 1 at the outlet, pin 2 goes to pin 2 etc. etc. The wire map also

checks for continuity, shorts, crossed pairs, reversed pairs and split pairs. A split pair is

probably the only thing that requires an explanation here, as they are undetectable with a

simple continuity tester. This is because pin for pin they seem to be correct. A balanced line

operation requires that the signal is transmitted over a pair of wires that are twisted

together. With a 'split pair' the signal would be split between two different pairs.

Return loss

When a cable is manufactured, there are slight imperfections in the copper. These

imperfections all contribute to the Structural Return Loss (SRL) measurement. Each one

causes an impedance mismatch, which adds to the cable's attenuation.

DC loop resistance

This is simply the resistance between the two conductors of a twisted pair which is looped

back at the far end. The primary purpose of this test is to make sure that there are no high

resistance connections in the link. Once you have completed the network upgrade, it is

suggested that a couple of computers are connected in a mesh-fashion to check their

connectivity and the success of the upgrade. A mesh network topology connects every PC,

or client machine, to every other machine in the topology. Using this configuration,

connectivity can be maintained in almost any situation. If there is a break in any of the

connections, there is at least one other way for those machines to communicate.

Because of this topology's complex nature, it is very difficult to network more than a few

machines, and it can be very expensive. It is most advantageous for the likes of financial

institutions where information is most critical. Because a mesh topology requires that each

client be connected to every other client, the chance that a client would lose communication

to the others is extremely small.

These networks are very expensive to install and very complex to implement, and are

common in banks, where constant uptime is critical. The mesh topology provides the most

redundancy in networking because it physically connects each PC with every other PC. It is

very complex and therefore very costly, but if you get a break between any of the PCs, you've

got at least one other way of connecting them.

ccess to the network is provided according to organisation policies,

procedures and specifications.

Why we need administration tools

As a Network Administrator you will be responsible for the smooth running of the network.

Networks are now critical in many organisations and failure cannot be tolerated. You must

be proactive in your role and use all necessary tools to ensure that the network operates as

the organisation expects it to.

Many of these administration tools will be built into either the operating system or the

network hardware itself. In addition, third party organisations may provide generic

administration tools that work with different operating systems and hardware and so provide

a central point of control to perform a number of administration tasks.

In selecting appropriate administration tools, you will need to consider:

The organisational policies and procedures

The type and level of services required

Whether to recommend to management that they invest in any third party products.

In this topic we will show you how to review organisational policies to identify the need for

network administration. You will then see how to identify the appropriate tools and to make

suggestions to fill in any gaps in requirements.

Reviewing organisational policies on network use and administration

Policy review

What will you be looking for?

Most organisations should have developed policies and procedures which detail how the

network is to be operated and maintained. As the network administrator you should be

aware of the requirements that these place on you and while it is great service to exceed

requirements, you should be making sure that you at least meet expected outcomes.

So the first thing you need to do is to review the relevant parts of these documents. You may

find that the policies and procedures manual is a printed, hard copy document or you may

find that it is online and accessible across the Intranet. Either way you have a duty to be

aware of the contents of these documents and be especially cognisant of those that directly

impact your administration role.

The Service Level Agreement (SLA)

Your organisation may also have a published a Service Level Agreement (SLA) between the

network group and the user community. This will also contain essential information about

the performance and operation of the network that you will need to know in order to develop

your administration routines and thus identify the resources and systems that you require.

There are likely to be three main areas to consider when identifying administration policy

requirements:

1 regular administration requirements that should be undertaken as a matter of course

2 ad-hoc administration requirements such as certain troubleshooting routines that are

needed on demand

3 performance related administration which is required to ensure that the network

continues to deliver to users.

The SLA should also include details of performance metrics to identify whether the

administration is meeting targets. If this is the case then you may want to also review these

statistics.

Reflection

Can you think of other documents that the administrator could review to identify

administration policy requirements?

Feedback

There could be help desk statistics or incident logs that may be used to identify problems

that could be the result of poor administration routines. If any network or IT committees

meet regularly, the minutes of these meetings may again have identified administration

issues.

What is administration?

As you look through the various documents you will need to identify those policies or SLA

requirements that are squarely administration activities and those that fall into other

categories such as help desk procedures, response times, etc. While the exact determination

of your role as an administrator will vary from organisation to organization, in this topic we

will be looking at the following tasks as part of an administrator’s job:

Configuration and documentation of network settings

Checking applications are network capable

Designing and building network folder structures

Securing user accesses

Managing user accounts

Maintaining network services

Managing virus prevention strategies.

Network risk analysis

Ongoing network security.

Before you undertake any of these roles you will need to know what the policies say, or what

the SLA requires, in each area. Then you can review the tools to assist you in your regular,

ad-hoc or performance related work.

Reflection

What else may an administrator be required to do?

Feedback

Administrators could also be required to:

Recommend hardware purchases and/or upgrades.

Carry out backups and restores.

Monitor network traffic and analyse performance.

Advise on standard operating environments across client computers.

Maintain Wide Area Networks (WAN).

Manage the intranet website.

As you can see the role of a network administrator is varied and challenging

forecast of the consumption of computer system consumables is

justified using measurement of historical consumption and anticipated

events.

LAN consumables are items that can be used for the running and upkeep of the network.

These items are required for the network but they are quite expensive to keep in stock for an

indefinite period, in anticipation for use. The longer you keep these items in stock, the more

the probability is that they will be outdated when you need to use them. Therefore it is of

utmost important that you only keep in stick exactly what you need, and to be able to

exchange items with your suppliers when there are newer versions available.

Examples of LAN consumables which should be kept in stock, are:

LAN cards (PCI)

LAN Cables

By keeping in mind the amount of these items used on average, in the past, you would be

able to estimate accurately how many you should keep in stock for emergency use. Keep in

mind that the suppliers are more than willing to deliver during the same day of ordering, so

extensive stock tallies are not required.

upply agreements are established and maintained so that the

consumable supplies are available to meet demand.

The best manner to ensure that there is a constant supply of items required is to

come to agreement with the supplier to supply you on a need to use-basis. Coming

to an agreement with the supplier is the ultimate goal of this type of exercise, where the

supplier will secure the agreement with you to supply you with the agreed items.

It is generally accepted to ask the supplier to have a look at your network so that they can

familiarise themselves with it, in order for them to provide you with assistance and advice

when required.

Maintain supply of consumables for a LAN Time: 120 minutes Activity: Self and Group

tocks of consumable supplies meet forecasted demand.

A local area network (LAN) is a computer network that interconnects computers

within a limited area such as a residence, school, laboratory, university campus or

office building. By contrast, a wide area network (WAN) not only covers a larger

geographic distance, but also generally involves leased telecommunication circuits.

Ethernet and Wi-Fi are the two most common technologies in use for local area networks.

Historical network technologies include ARCNET, Token ring, and AppleTalk.

Cabling

Early Ethernet (10BASE-5 and 10BASE-2) used coaxial cable. Shielded twisted pair was used

in IBM's Token Ring LAN implementation. In 1984, StarLAN showed the potential of

simple unshielded twisted pair by using Cat3 cable—the same cable used for telephone

systems. This led to the development of 10BASE-T (and its successors) and structured

cabling which is still the basis of most commercial LANs today.

While optical fiber cable is common for links between network switches, use of fiber to the

desktop is rare.

Wireless media

In a wireless LAN, users have unrestricted movement within the coverage area. Wireless

networks have become popular in residences and small businesses, because of their ease of

installation. Most wireless LANs use Wi-Fi as it is built into smartphones, tablet

computers and laptops. Guests are often offered Internet access via a hotspot service.

Technical aspects

Network topology describes the layout of interconnections between devices and network

segments. At the data link layer and physical layer, a wide variety of LAN topologies have

been used, including ring, bus, mesh and star.

Simple LANs generally consist of cabling and one or more switches. A switch can be

connected to a router, cable modem, or ADSL modem for Internet access. A LAN can include

a wide variety of other network devices such as firewalls, load balancers, and network

intrusion detection. Advanced LANs are characterized by their use of redundant links with

switches using the spanning tree protocol to prevent loops, their ability to manage differing

traffic types via quality of service (QoS), and their ability to segregate traffic with VLANs.

At the higher network layers, protocols such as NetBIOS, IPX/SPX, AppleTalk and others

were once common, but the Internet protocol suite (TCP/IP) has prevailed as the standard of

choice. LANs can maintain connections with other LANs via leased lines, leased services, or

across the Internet using virtual private network technologies. Depending on how the

connections are established and secured, and the distance involved, such linked LANs may

also be classified as a metropolitan area network (MAN) or a wide area network (WAN).

verstocks of consumable supplies are avoided.

Avoid it

Obviously, the best way to eliminate the cost of surplus inventory is to avoid it all

together. Industrial distributors know that's often easier said than done. By

reacting quickly to accurate customer and vendor intelligence, improving the procurement

and inventory processes, and changing ineffective processes and procedures, you can

succeed in avoiding some level of surplus inventory.

One Midwest industrial fastener distributor succeeded in doing just that. The distributor

planned inventory requirements and stocking levels using customer-supplied forecasts.

Customers provide their estimated annual usage and a normal replenishment quantity. By

combining these estimates with actual demand history, the distributor determined a stocking

level and passed that information onto its manufacturers.

Manufacturers then used this data to ensure on-hand quantities reflected forecasted needs

and produced only what was required. The distributor improved service levels and could now

order just in time. In this case, inventory managers cut inventory stocking levels by up to 50

percent while service levels remained stable.

As with any improvement project, distributors must begin by determining where within their

organization lies the largest opportunity to avoid surplus inventory. Companies may want to

consider improvements in the following areas.

Collect accurate customer and vendor intelligence-and react quickly. Industrial distributors

must find ways to understand customer requirements and current trends or promotions in

order to generate accurate sales forecasts. The more quickly you know about an order

change, a quality or cost issue or a service concern, the more quickly you can react.

An online, fully integrated Web site that allows customers to access product information,

review and update demand requirements, enter orders or change existing orders gives you

immediate, real-time access to customer decisions. A well-trained sales force tuned into

customer needs can also be a valuable source of intelligence.

On the vendor side, you must maintain constant communication with suppliers to ensure

timely knowledge about discontinued products, product recalls, planned obsolescence and

warranty issues. Ideally, you and your suppliers should have visibility into one another's

pipelines so that all parties have real-time information to make the best business decisions.

Exchanging production and requirements information through daily reports or e-mail file

transfers may improve communication. Establishing a vendor rating program based on

suppliers' responsiveness, accuracy of information and other criteria may also help.

Get demand and inventory information under control.

Managing the tremendous amount of information that revolves around demand, products

and inventory is probably the single most difficult-yet most critical-task to accomplish in

order to avoid surplus inventory. Industrial distributors must maintain accurate demand

statistics by item, product, period, location and customer. It's critical to implement a

business system that allows tracking of promotional, internal transfer, component, special

order and direct demand. Order cancellations and substitution demand can erroneously

boost demand data.

Classify items based on product life cycle such as "new," "rising," or "declining." Also classify

items by customer agreement and demand pattern as well as by criticality, which refers to

slow-moving service items required to retain business.

Paint an accurate "big picture." Once you have your demand and inventory information

under control, get the details of the "big picture" in order. Understand each combination of

stocking location, buyer, product category, supplier and functional classifications.

For example, anticipate demand surges or droughts or take advantage of current costs to

avoid anticipated price increases. Balance consumption rates against efficient production

and fulfilment rates, and transportation inventories need to cover all stops along a product's

journey.

Manage stocking inventory by days of supply, lost control for shelf life and aging analysis.

Non-stocking inventory (or items that should have zero on-hand balances) should include

only direct ship, special order, obsolete or de-listed items. Review and change company

policies to minimize surplus inventory. Review existing company policies, which should

provide safeguards against surplus inventory-not encourage additional purchasing and

stocking.

Policies dictating purchasing and replenishment decisions should keep the "days of supply"

requirement low and adjust forecasting to reflect different product life cycle stages. Avoid

vendor super sales unless there is significant ROI. Take the time to find flexible vendors that

accept forecasting requirements and will ship based on demanded quantities instead of pre-

determined minimum quantities. Be sure that supplier backorders can be cancelled within a

generous time frame.

Stocking policies should include "no returns after" and "no returns before" deadlines. Create

incentives to encourage customers to accept a total quantity of special items. Implement

customer end-of-life and final sales agreements, which require customers to purchase all on-

hand quantities at a set time. Enforce strict write-off policies to ensure timely stock

elimination and then immediately scrap the products

he plan includes a forecast based on documentation of current network

resource utilisation, historical growth and future plans.

Capacity planning for the core network is the process of ensuring that sufficient

bandwidth is provisioned such that the committed core network service-level

agreement (SLA) targets of delay, jitter, loss, and availability can be met. In the core network,

where link bandwidths are high and traffic is highly aggregated, the SLA requirements for a

traffic class can be translated into bandwidth requirements, and the problem of SLA

assurance can effectively be reduced to that of bandwidth provisioning. Hence, the ability to

meet SLAs is dependent on ensuring that core network bandwidth is adequately provisioned,

which depends in turn on core capacity planning.

The simplest core capacity planning processes use passive measurements of core link

utilization statistics and apply rules of thumb, such as upgrading links when they reach 50

percent average utilization, or some other general utilization target. The aim of such simple

processes is to attempt to ensure that the core links are always significantly overprovisioned

relative to the offered average load, on the assumption that this will ensure that they are also

sufficiently overprovisioned relative to the peak load, that congestion will not occur, and

hence that the SLA requirements will be met.

There are, however, two significant consequences of such a simple approach. First, without a

network wide understanding of the traffic demands, even an approach that upgrades links

when they reach 50 percent average utilization may not be enough to ensure that the links

are still sufficiently provisioned to meet committed SLA targets when network element (for

example, link and node) failures occur.

Second, and conversely, rule-of-thumb approaches such as this may result in more capacity

being provisioned than is actually needed. Effective core capacity planning can overcome

both of these issues. Effective core capacity planning requires a way of measuring the

current network load, as well as a way of determining how much bandwidth should be

provisioned relative to the measured load in order to achieve the committed SLAs.

Plan capacity for a LAN Time: 120 minutes Activity: Self and Group

Hence, in this white paper we present a holistic methodology for capacity planning of the

core network that takes the core traffic demand matrix and the network topology into

account. This methodology determines how much capacity the network needs in order to

meet the committed SLA requirements, taking network element failures into account if

necessary, while minimizing the capacity and cost associated with overprovisioning.

The methodology presented here can be applied whether Differentiated Services (DiffServ) is

deployed in the core or not. Where DiffServ is not deployed, capacity planning is performed

on aggregate. Where DiffServ is deployed, although the fundamental principles remain the

same, capacity planning per traffic class is needed to ensure that class SLA targets are not

violated.

Capacity Planning Methodology

Capacity planning involves the following steps:

1. Collect the core traffic demand matrices (either on aggregate or per class) and add

traffic growth predictions to create a traffic demand forecast.

2. Determine the appropriate bandwidth overprovisioning factors (either on aggregate or

per class), relative to the measured demand matrices, to ensure that committed SLAs can be

3. Run simulations to overlay the forecasted demands onto the network topology, taking

failure cases into account if necessary, to determine the forecasted link loadings. Analyse the

results, comparing the forecasted link loadings against the provisioned bandwidth and

taking the calculated overprovisioning factors into account, to determine the future capacity

provisioning plan required to achieve the desired SLAs.

Collecting the Traffic Demand Matrices

The core traffic demand matrix is the matrix of ingress-to-egress traffic demands across the

core network. Traffic matrices can be measured or estimated to different levels of

aggregation: by IP prefix, by router, by point of presence (POP), or by autonomous system

The benefit of a core traffic matrix over simple per-link statistics is that the demand matrix

can be used in conjunction with an understanding of the network routing model to predict

the impact that demand growth can have and to simulate “what-if” scenarios, in order to

understand the impact that the failure of core network elements can have on the (aggregate

or per-class) utilization of the rest of the links in the network.

With simple per-link statistics, when a link or node fails, in all but very simple topologies it

may not be possible to know over which links the traffic affected by the failure will be

rerouted. Core network capacity is increasingly being provisioned with the failure of single

network elements taken into account.

To understand traffic rerouting when an element fails, one must have a traffic matrix that

aggregates traffic at the router-to-router level. If DiffServ is deployed, a core traffic matrix

aggregated per class of service (CoS) is highly desirable.

The core traffic demand matrix can be an internal traffic matrix (that is, router to router) or

an external traffic matrix (that is, router to AS), as illustrated in Figure 2, which shows the

internal traffic demand matrix from one distribution router (DR) and the external traffic

demand matrix from another.

The internal traffic matrix is useful for understanding the impact that internal network

element failures will have on the traffic loading within the core. An internal matrix could also

be edge to edge (for example, DR to DR) or just across the inner core (for example, core router

[CR] to CR); a DR-to-DR matrix is preferred, as this can also be used to determine the impact

of failures within a POP.

The external traffic matrix provides additional context, which could be useful for managing

peering connection capacity provision, and for understanding where internal network failures

might affect the external traffic matrix, due to closest-exit (also known as “hot potato”)

routing.

he plan includes recommendations for network changes that allow the

network to meet the future capacity requirements

There are a number of possible approaches for collecting the core traffic demand

matrix statistics. The approaches differ in terms of their ability to provide an

internal or external matrix, whether they can be applied to IP or MPLS, and whether they can

provide a per-CoS traffic matrix.

Further, the capabilities of network devices to provide the information required to determine

the core traffic matrix can vary depending on the details of the particular vendor’s

implementation. The sections that follow discuss some of the possible approaches for

determining the core traffic demand matrix.

IP Flow Statistics Aggregation

The IP Flow Information eXport (IPFIX) protocol has been defined within the Internet

Engineering Task Force (IETF) as a standard for the export of IP flow information from

routers, probes, and other devices. If edge devices such as distribution routers are capable of

accounting at a flow level (that is, in terms of packet and byte counts), a number of potential

criteria could be used to aggregate this flow information - potentially locally on the device - to

produce a traffic matrix.

When the Border Gateway Protocol (BGP) is used within an AS, for example, each router at

the edge of the AS is referred to as a BGP “peer.” For each IP destination address that a peer

advertises via BGP, it also advertises a BGP next-hop IP address, which is used when

forwarding packets to that destination.

To forward a packet to that destination, another BGP router within the AS needs to perform

a recursive lookup, first looking in its BGP table to retrieve the BGP next-hop address

associated with that destination address and then looking in its Interior Gateway Protocol

(IGP) routing table to determine how to get to that particular BGP next-hop address. Hence,

aggregating IPFIX flow statistics based on the BGP next-hop IP address used to reach a

particular destination would produce an edge router to edge router traffic matrix.

MPLS LSP Accounting

When MPLS is used, a label switched path (LSP) implicitly represents an aggregate traffic

demand. When BGP is deployed in conjunction with label distribution by the Label

Distribution Protocol (LDP), in the context of a BGP MPLS VPN service, for example, and each

provider edge (PE) router is a BGP peer, an LSP from one PE to another implicitly represents

the PE-to-PE traffic demand.

The distribution routers in the generalized network reference model we use in this paper will

normally be PE routers in the context of an MPLS VPN deployment. Hence, if traffic

accounting statistics are maintained per LSP, these can be retrieved, using Simple Network

Management Protocol (SNMP), for example, to produce the PE-to-PE core traffic matrix.

If MPLS traffic engineering is deployed with a full mesh of traffic engineering (TE) tunnels,

each TE tunnel LSP implicitly represents the aggregate demand of traffic from the head-end

router at the source of the tunnel to the tail-end router at the tunnel destination.

Hence, if traffic accounting statistics are maintained per TE tunnel LSP, these can be

retrieved, using SNMP, for example, to understand the core traffic matrix. If DiffServ-aware

TE is deployed with a full mesh of TE tunnels per class of service, the same technique could

be used to retrieve a per-traffic-class traffic matrix.

Demand Estimation

Demand estimation is the application of mathematical methods to measurements taken from

the network, such as core link usage statistics, in order to infer the traffic demand matrix

that generated those usage statistics.

A number of methods have been proposed for deriving traffic matrices from link

measurements and other easily measured data, and there are a number of commercially

available tools that use these or similar techniques to derive the core traffic demand matrix.

If link statistics are available on a per-traffic-class basis, these techniques can be applied to

estimate the per-CoS traffic matrix.

Examples of demand estimation include the gravity model, tomogravity, and Cariden’s

patented Demand Deduction. The accuracy and usefulness of the results depend on many

factors, including how much measured traffic is available, and of what type. Demand

Deduction is especially accurate in the practical cases of predicting the overall utilization

after a failure, a topology change, or a metric change.

Retrieving and Using the Statistics

Whichever approach is used to determine the core traffic matrix, the next decision to be

made is how often to retrieve the measured statistics from the network. The retrieved

statistics will normally be in the form of packet and byte counts, which can be used to

determine the average traffic demands over the previous sampling interval.

The longer the sampling interval (that is, the less frequently the statistics are retrieved), the

greater the possibility that significant variation in the traffic during the sampling interval

may be hidden due to the effects of averaging.

Conversely, the more frequently the statistics are retrieved, the greater the load on the

system retrieving the data, the greater the load on the device being polled, and the greater

the polling traffic on the network. Hence, in practice the frequency with which the statistics

are retrieved is a balance that depends on the size of the network; in backbone networks it is

common to collect these statistics every 5, 10, or 15 minutes.

The measured statistics can then be used to determine the traffic demand matrix during

each interval. In order to make the subsequent stages of the process manageable, it may be

necessary to select some traffic matrices from the collected data set.

A number of possible selection criteria could be applied; one possible approach is to sum the

individual (that is, router-to-router) traffic demands within each interval, and to take the

interval that has the greatest total traffic demand, (that is, the peak). Alternatively, to be

sensitive to outliers (for example, due to possible measurement errors), a high percentile

interval such as the 95th percentile (P95) could be taken, that is, the interval for which more

than 95 percent of the intervals have a lower value.

In order to be representative, the total data set should be taken over at least a week, or

preferably over a month, to ensure that trends in the traffic demand matrices are captured.

In the case of a small network, it might be feasible to use all measurement intervals (for

example, all 288 daily measurements for 5-minute intervals), rather than to use only the

peak (or percentile of peak) interval. This will give the most accurate simulation results for

the network.

In geographically diverse networks, regional peaks in the traffic demand matrix may occur at

a time of the day when the total traffic in the network is not at its maximum. In a global

network, for example, the European region may be busy during morning office hours in

Europe, while at the same time the North American region is relatively lightly loaded.

It is not very easy to detect regional peaks automatically, and one alternative approach is to

define administrative capacity planning network regions (for example, United States, Europe,

and Asia), and apply the previously described procedure per region, to give a selected per-

region traffic matrix.

Once the traffic matrix has been determined, other factors may need to be taken into

account, such as anticipated traffic growth. Capacity planning will typically be performed

looking sufficiently far in advance that new bandwidth can be provisioned before network

loading exceeds acceptable levels.

If it takes three months to provision or upgrade a new core link, for example, and capacity

planning is performed monthly, the capacity planning process would need to try to predict

bandwidth requirements at least four months in advance.

If expected network traffic growth within the next four months was 10 percent, for example,

the current traffic demand matrix would need to be multiplied by a factor of at least 1.1.

Service subscription forecasts may be able to provide more granular predictions of future

demand growth, possibly predicting the increase of particular traffic demands.

he plan identifies and explains the feasibility of the recommendations.

Determining Appropriate Overprovisioning Factors

The derived traffic matrices described in the previous section are averages taken

over the sample interval; hence, they lack information on the variation in traffic

demands within each interval.

There will invariably be bursts within the measurement interval that are above the average

rate. If traffic bursts are sufficiently large, temporary congestion may occur, causing delay,

jitter, and loss, which may result in the violation of SLA commitments even though the link

is, on average, not 100 percent utilized.

To ensure that bursts above the average do not affect the SLAs, the actual bandwidth may

need to be overprovisioned relative to the measured average rates. Hence, a key capacity

planning consideration is to determine the amount by which bandwidth needs to be

overprovisioned relative to the measured average rate, in order to meet a defined SLA target

for delay, jitter, and loss. We define this as the overprovisioning factor (OP).

The overprovisioning factor required to achieve a particular SLA target depends on the arrival

distribution of the traffic on the link, and the link speed. Opinions remain divided on what

arrival distribution describes traffic in IP networks. One view is that traffic is self-similar,

which means that it is bursty on many or all timescales (that is, regardless of the time period

the traffic is measured over, the variation in the average rate of the traffic stream is the

same).

An alternative view is that IP traffic arrivals follow a Poisson (or more generally Markovian)

arrival process. For Poisson distributed traffic, the longer the time period over which the

traffic stream is measured, the less variation there is in the average rate of the traffic stream.

Conversely, the shorter the time interval over which the stream is measured, the greater the

visibility of burst or the burstiness of the traffic stream.

For Poisson traffic, queuing theory shows that as link speeds increase and traffic is more

highly aggregated, queuing delays reduce for a given level of utilization. For self-similar

traffic, however, if the traffic is truly bursty at all timescales, the queuing delay would not

decrease with increased traffic aggregation.

However, while views on whether IP network traffic tends toward self-similar or Poisson are

still split, this does not fundamentally affect the capacity planning methodology we are

describing. Rather, the impact of these observations is that, for high-speed links, the

overprovisioning factor required to achieve a specified SLA target would need to be

significantly greater for self-similar traffic than for Poisson traffic.

Note: A number of studies, both theoretical and empirical, have sought to quantify the

bandwidth provisioning required to achieve a particular target for delay, jitter, and loss,

although none of these studies has yet been accepted as definitive. In the rest of this section,

by way of example, we use the results attained in the study by Telkamp to illustrate the

capacity planning methodology. We chose these results because they probably represent the

most widely used guidance with respect to core network overprovisioning.

To determine the overprovisioning factors required to achieve various SLA targets,

researchers captured a number of sets of packet-level measurements from an operational IP

backbone carrying Internet and VPN traffic. The traces were used in simulation to determine

the bursting and queuing of traffic at small timescales over this interval, as a means of

identifying the relationship between measures of link utilization that can be easily obtained

with capacity planning techniques (for example, 5-minute average utilizations) and queuing

delays experienced in much smaller timeframes.

By using traces of actual traffic, they avoided the need to make assumptions about the

nature of the traffic distribution. Each set of packet measurements or “trace” contained

timestamps in microseconds of the arrival time for every packet on a link, over an interval of

minutes. The traces, each with a different average rate, were then used in a simulation in

which multiple traces were multiplexed together and the resulting trace was run through a

simulated fixed-speed queue (for example, at 622 Mbps).

In this example, three traces with 5-minute average rates of 126 Mbps, 206 Mbps, and 240

Mbps are multiplexed together, resulting in a trace with a 5-minute average rate of 572

Mbps, which is run through a 622-Mbps queue (that is, at a 5-minute average utilization of

92 percent). The queue depth was monitored during the simulation to determine how much

queuing delay occurred. This process was then repeated with different mixes of traffic;

because each mix had a different average utilization, multiple data points were produced for

a specific interface speed.

After performing this process for multiple interface speeds, the researchers derived results

showing the relationship between average link utilization and the probability of queuing

delay. The graph in Figure 5 uses the results of this study to show the relationship between

the measured 5-minute average link utilization and queuing delay for a number of link

speeds. The delay value shown is the P99.9 delay, meaning that 999 out of 1000 packets will

have a delay caused by queuing that is lower than this value.

The x-axis in Figure 5 represents the 5-minute average link utilization; the y-axis represents

the P99.9 delay. The lines show fitted functions to the simulation results for various link

speeds, from 155 Mbps to 2.5 Gbps. Note that other relationships would result if the

measured utilization was averaged over longer time periods (such as 10 minutes or 15

minutes), as in these cases there may be greater variations that are hidden by averaging, and

hence lower average utilizations would be needed to achieve the same delay.

The results in Figure 5 show that for the same relative levels of utilization, shorter delays are

experienced for 1-Gbps links than for 622-Mbps links; that is, the level of overprovisioning

required to achieve a particular delay target reduces as link bandwidth increases, which is

indicative of Poisson traffic.

Taking these results as an example, we can determine the overprovisioning factor that is

required to achieve particular SLA objectives. For example, if we assume that DiffServ is not

deployed in the core network, and we want to achieve a target P99.9 queuing delay of 2 ms

on a 155-Mbps link, then using Figure 5, we can determine that the 5-minute average link

utilization should not be higher than approximately 70 percent or 109 Mbps (that is, an OP

of 1/0.7 = 1.42 is required), meaning that the provisioned link bandwidth should be at least

1.42 times the 5-minute average link utilization.

To achieve the same objective for a 1-Gbps link, the 5-minute average utilization should be

no more than 96 percent or 960 Mbps (OP = 1.04).

Table 1. P99.9 Delay Multiplication Factors

Number of Hops Delay Multiplication Factor

Although the study by Telkamp did not focus on voice traffic, in similar studies by the same

authors for voice over IP (VoIP)-only traffic (with silence suppression), the OP factors required

to achieve the same delay targets were similar. We can apply the same principle on a per-

class basis when DiffServ is deployed. To assure a P99.9 queuing delay of 1 ms for a class

serviced with an assured forwarding (AF) per-hop behaviour (PHB), providing a minimum

bandwidth assurance of 622 Mbps (that is, 25 percent of a 2.5-Gbps link), the 5-minute

average utilization for the class should not be higher than approximately 85 percent, or 529

Considering another example, to ensure a P99.9 queuing delay of 500 microseconds for a

class serviced with an expedited forwarding (EF) PHB implemented with a strict priority

queue on a 2.5-Gbps link, as the scheduler servicing rate of the strict priority queue is 2.5

Gbps, the 5-minute average utilization for the class should not be higher than approximately

92 percent, or 2.3 Gbps (OP = 1.09) of the link rate. Note that these results are for queuing

delay only and exclude the possible delay impact on EF traffic due to the scheduler and the

interface first in, first out (FIFO) behaviour.

The delay that has been discussed so far is per link and not end-to-end across the core. In

most cases, traffic will traverse multiple links in the network and hence will potentially be

subject to queuing delays multiple times. Telkamp’s results show that the P99.9 delay was

not additive over multiple hops; rather, Table 1 shows the delay “multiplication factor”

experienced over a number of hops relative to the delay over a single hop.

If the delay objective across the core is known, the overprovisioning factor that needs to be

maintained per link can be determined. The core delay objective is divided by the

multiplication factor from Table 1 to find the per-hop delay objective. This delay can then be

looked up in the graph in Figure 5 to find the maximum utilization for a specific link capacity

that will meet this per-hop queuing delay objective.

Consider, for example, a network comprising 155-Mbps links with a P99.9 delay objective

across the core network of 10 ms, and a maximum of 8 hops. Table 1 shows that the 8 hops

cause a multiplication of the per-link number by 3.3, so the per-link objective becomes 10

ms/3.3 = 3 ms.

he plan includes a comparison of actual resource usage with forecast

usage according to organisation requirements.

Collecting and Reporting Capacity Information

Collecting and reporting capacity information should be linked to the three

recommended areas of capacity management:

What-if analysis, which centers on network change and how the change affects the

environment

Baselining and trending

Exception management

Within each of these areas, develop an information collection plan. In the case of network or

application what-if analyses, you need tools to mimic the network environment and to

understand the affect of the change relative to potential resource issues within the device

control plane or the data plane. In the case of baselining and trending, you need snapshots

for devices and links showing current resource utilization.

You then review the data over time to understand potential upgrade requirements. This

allows network administrators to properly plan upgrades before capacity or performance

problems arise. When problems do arise, you need exception management to alert the

network administrators so they can tune the network or fix the problem.

This process can be divided into the following steps:

Determine your needs.

Define a process.

Define capacity areas.

Define the capacity variables.

Interpret the data.

Determine your Needs

Developing a capacity and performance management plan requires understanding the

information you need and the purpose of that information. Split the plan into three required

areas: one each for what-if analysis, baselining/trending, and exception management. Within

each of these areas, discover what resources and tools are available and what is needed.

Many organization fail with tool deployments because they consider the technology and

features of the tools but don't consider the people and expertise needed to manage the tools.

Include the required people and expertise in your plan, as well as process improvements.

These people may include system administrators to manage the network management

stations, data base administrators to help with database administration, trained

administrators to use and monitor the tools, and higher level network administrators to

determine policies, thresholds, and information collection requirements.

Define a Process

You also need a process to ensure that the tool is used successfully and consistently. You

may require process improvements to define what network administrators should do when

threshold violations occur or what process to follow for baselining, trending, and upgrading

the network. Once you determine the requirements and resources for successful capacity

planning, you can consider the methodology. Many organizations choose to outsource this

type of functionality to a network services organization such as INS or build the expertise in-

house because they consider the service a core competency.

Define Capacity Areas

The plan for capacity planning should also include a definition of capacity areas. These are

areas of the network that can share a common capacity planning strategy: for example, the

corporate LAN, WAN field offices, critical WAN sites, and dial-in access. Defining different

areas is helpful for several reasons:

Different areas may have different thresholds. For example, LAN bandwidth is much cheaper

than WAN bandwidth so utilization thresholds should be lower.

Different areas may require monitoring different MIB variables. For instance, FECN and

BECN counters in Frame Relay are critical in understanding frame-relay capacity problems.

It may be more difficult or time consuming to upgrade some areas of the network. For

example, international circuits can have much longer lead times and need a corresponding

higher level of planning.

Define the Capacity Variables

The next important area is defining the variables to monitor and the threshold values that

require action. Defining the capacity variables significantly depends on the devices and

media used within the network. In general parameters such as CPU, memory and link

utilization are valuable. However, other areas may be important for specific technologies or

requirements. These may include queue depths, performance, frame-relay congestion

notification, backplane utilization, buffer utilization, netflow statistics, broadcast volume,

and RMON data. Keep in mind your long term plans, but start with only a few key areas to

help ensure success.

Interpret the Data

Understanding the collected data is also key to providing a high-quality service. For instance,

many organizations don't fully understand peak and average utilization levels. The following

diagram shows a capacity parameter peak based on a 5 minute SNMP collection interval,

(shown in green).

Even though the reported value was less than the threshold (shown in red) peaks still can

occur within the collection interval that are above the threshold value (shown in blue). This is

significant because during the collection interval, the organization may be experiencing peak

values that affect performance or capacity of the network. Be careful to select a meaningful

collection interval that is useful and that does not cause excessive overhead.

Another example is average utilization. If employees are only in the office from eight to five,

but the average utilization is 7X24, the information may be misleading

he network is available and accessible according to organisation

requirements.

LAN stands for Local Area Network, LAN (Local Area Network) is a network which is

established to meet the needs of small areas. It can be applied to home, offices,

airports and in small college computer labs. The idea of developing LAN is to utilize the fast

data transfer over a small geographical area. LAN (Local Area Network) was developed with a

view to establish better interconnections within the individual computer units. LAN (Local

Area Network) network is preferred due to its fast access and affordability. LAN (Local Area

Network) is employed to build successful sophisticated network for data sharing.

How LAN Works

Early LAN (Local Area Network) networks were formed using coaxial cable, coax is an electric

cable and it is used to carry radio signals. LAN (Local Area Network) setup is developed by

connecting two or more than two computers with each other using a physical connection in

order to share files and data overtime. The basic application of this cable is to connect the

radio transmitters with their antennas.

However it is also used for developing internet connections and for distributing cable

channels. Most common type of developing LAN (Local Area Network) network is the

Ethernet. Ethernet is usually termed as a major data and physical link layer technology.

Ethernet is often associated with the name of engineer Robert Metcalfe. Ethernet today can

give the maximum data rate of up to 100 Mbps.

Ethernet has proved to be an effective way to serve as a data transfer medium for internet

protocols. Usually Ethernet cables are extended to the length of 100 meters, but this is not

the ultimate limit. Ethernet cables can be extended according to the need. When you decide

to develop a LAN (Local Area Network), try to use the specialized software like the Microsoft

windows. Microsoft widows provide special internet sharing features which help LAN (Local

Area Network).

Maintain the availability of a LAN Time: 120 minutes Activity: Self and Group

Wireless Local Area Network (WLAN)

The wireless connection that enables you to connect with your LAN (Local Area Network),

while you move around is known as WLAN or wireless local area network. The worldwide

trend of carrying and using laptops has decreased the use of traditional LANs. Moreover the

office workers who possess laptops often prefer WLAN, so that they can do their office work

at home while they remain connected to their LAN.

WLAN are admired due to their ease of installment and wireless arrangements. The first

wireless LAN was ALOHA net, which was invented by Norman Abramson In 1970.wireless

distribution system is the one in which many different access points are linked without the

Hassel of wires involved. Wireless LANs are of many types. Wireless LAN can be peer to peer

or can be an adhoc network.

Application of LAN and benefits of LAN

Applications of LAN (Local Area Network) is widely used in universities, some banks, in

homes and in some air reservation systems. LAN enables you to store data in any central

computer from where it can be shared throughout the organization. File transfer and

recovery is easy in a LAN (Local Area Network) network because backup files are stored in a

single server.

Restricted LAN PCs offers enough security to the data because only authentic users can

share and access data. LAN (Local Area Network) helps you to save the installation cost of

various soft wares, because resources are managed and shared centrally. Moreover expensive

hardware devices such as laser printers, CD writers and scanners can be used equally from

each individual unit.

User files can be accessed from many different workstations. The ease of sharing resources

and hardware devices reduces the cost of employing independent printers and scanners. This

sharing reduces cost and increases productivity. The risk of data loss is reduced due to the

effective physical backup system. The recovery of lost data with the help of data recovery soft

wares involves additional cost. However physical backup support also helps to cover this

additional cost.

etwork availability problems are resolved according to organisation

specifications.

Networks are networks. Despite best efforts to keep things smooth all the time

every day, things happen. Here’s a look at some common network issues, some

tips for quickly resolving them, and even better, how to prevent them from occurring again.

1. Duplicate IP Addresses

When two devices attempt to share a single IP, you see the dreaded “Address Already in Use”

error — with no ability to access the network. The Quick Fix: The blame for this often rests

with your router’s default DHCP configuration. DHCP is probably trying to assign your new

device an address at the beginning of your subnet, and another device may already occupy

these low-numbered addresses with static IPs.

If you’ve just introduced a new device or server to your network, it may have its own DHCP

server. Simply disable the DHCP server on that device to restore sanity to your network. The

Preventive Measure: You can take one simple step to avoid IP conflicts by modifying your

router’s configuration to begin assigning DHCP addresses near the top end of your subnet,

leaving the lower addresses available for devices that require static IPs.

2. IP Address Exhaustion

To troubleshoot this issue, use the ipconfig command. If the workstation has assigned itself

an IP address that begins with 169.x.x.x, it means that no IP address was available from the

DHCP server. The Quick Fix: Some users on cable internet might not have a local router, in

which case IP addresses are assigned on a limited basis directly from your ISP. You have

probably run out of allowed IP addresses from your ISP. The solution to this is to purchase

either a standalone router or WiFi access point with an integrated router. This creates your

own local pool of internal addresses, ensuring you won’t run out.

If you already have a local router with DHCP, the default address pool might be too small for

your network. By accessing the DHCP settings on the router, you can adjust the size of the

address pool to meet your network’s needs. The Preventive Measure: It’s important that any

internet-connected network have a local router in operation with NAT and DHCP, both for

security reasons and to prevent IP address exhaustion. The router needs to be the only

device connected to the modem, with all other devices connecting through the router.

3. DNS Problems

Errors such as The Network Path Cannot Be Found, IP Address Could Not Be Found, or DNS

Name Does Not Exist, can usually be traced to a DNS configuration issue. The command line

utility nslookup can be used to quickly show a workstation’s DNS settings. The Quick

Fix: Workstations and other network devices can be configured to use their own DNS servers,

ignoring the server assigned by DHCP. Checking the ‘Internet Protocol Version 4 (TCP/IP)’

settings for your adapter will show if an incorrect DNS server is specified, so just select

“Obtain DNS server address automatically” instead.

The Prevention Measure: Your local router might be configured to operate as a DNS Server,

creating a DNS pass-through to your ISPs servers. On busy networks, this may overload the

capabilities of the router. Change your network’s DHCP settings to directly access your DNS

servers.

4. Single Workstation Unable to Connect to the Network

If only a single workstation is displaying the “No internet” message when opening a web

browser, we can usually assume that the rest of the network is healthy and turn our

attention to any hardware and software that is particular to this system. The Quick Fix: To

resolve this network issue, start by eliminating the obvious communication barriers such as

a bad cable, poor WiFi signal, failing network card or incorrect drivers. Ensure that the

workstation’s network adapter is configured with the correct IP, subnet, and DNS servers.

If that doesn’t solve the problem, check any firewall software on the device to ensure that

necessary ports are open to the external network. Common ports include 80 and 443 for web

traffic, plus 25, 587, 465, 110, and 995 for email. The Preventive Measure: It’s usually best

to leave all workstation TCP/IP settings to “Automatically assigned.” Use a DHCP server to

hand out a uniform configuration to all devices on the network. If a static IP is needed on a

particular workstation or server, most DHCP servers allow the ability to create static IP

mappings.

5. Unable to Connect to Local File or Printer Shares

Sharing problems are among the most difficult network problems to solve, due to the number

of components that need to be configured properly. Most commonly, sharing problems arise

due to conflicts between mixed security environments. Even different versions of the same

operating system sometimes use slightly different security models, which can make

interconnection of workstations difficult.

The Quick Fix: We can cure sharing problems most efficiently by drilling down through the

possibilities in this order:

Ensure that the required services are running. On Windows systems, the server, TCP/IP

NetBIOS Helper, workstation, and computer browser services all need to be running. On

Linux machines, Samba is the primary component required to share with Windows systems.

Check your firewall(s). It’s very common for a workstation’s firewall to be configured to block

file and printer sharing traffic, especially if a new antivirus package is installed that

introduces its own firewall. Firewall issues can also exist at the hardware level, so ensure

that routers or managed switches are passing share traffic within the subnet. Speaking of

subnet….

Ensure all workstations are on the same subnet. This problem typically only appears on

complex networks, however, even simple networks sometimes have static-IP equipment with

an improperly configured subnet. The result is that external traffic will move about just fine,

while internal traffic will hit unexpected roadblocks.

All Windows network adapters will need File and Printer Sharing for Microsoft Networks,

Client for Microsoft Networks, and NetBIOS over TCP/IP enabled. Once the above checks

have passed, it’s finally time to check the most likely culprit, permissions. There are multiple

layers of access required, each with their own interface within the OS. Check for:

Systems configured with the wrong workgroup or domain.

Incorrectly configured HomeGroup.

Network type set to Public.

Incorrect NTFS permissions.

6. Local Network is Unable to Connect to the internet

This situation can either be intermittent or persistent. Often times, the most difficult aspect

of dealing with any external network problem is finding the company responsible. And then

tasking them to solve the issue, particularly with intermittent failures that are difficult to

trace. It can sometimes be such a problem that organizations will have to switch internet

providers in order to solve the issue.

The Quick Fix: A router and modem reboot is the first order of business. The tracert then

utility can be used to identify communication breaks. It will clearly hiccup on the particular

router hop that is causing the problem. Contact your ISP with your findings, providing

screenshots as necessary.

The Preventive Measure: To avoid the finger-pointing that can prevent rapid resolution of

external issues, do some research to ensure that you procure connectivity only from local

Tier 1 providers. Other ISPs are more than happy to sell you service, however, they are

simply piggybacking the Tier 1 connection, since they don’t actually own the infrastructure

in your area. The goal is to remove as many middle-men as possible, so that when (not if) you

experience a problem, one phone call is all that is required to identify the issue and get

technicians to work on it.

7. Slow Internet Performance

Slow performance is typically due to congestion, or sometimes poor quality connections that

have corroded or otherwise deteriorated. Congestion may not be directly related to bandwidth

exhaustion, as a single overloaded port on a switch or router can diminish network

performance. This can be especially true on leased lines where dedicated bandwidth is to be

expected, but speed tests indicate the network is not reaching its rated potential.

The Quick Fix: Use speed test websites, conducting tests from geographically remote servers.

This can pinpoint areas of congestion on the ISP’s network. In the case of cable internet, the

local network is shared amongst your neighbours, committing your ISP to a costly bandwidth

upgrade when saturation occurs. Report your findings to your ISP so that they can take

steps to resolve the issue.

DNS servers are an often overlooked aspect of internet performance. Using incorrect DNS

servers can result in routing congestion or load balancing problems. While you should

typically use your ISP’s DNS settings whenever possible, they may actually be routing traffic

through overloaded web caches. You can temporarily adjust your DNS settings to use

OpenDNS instead.

The Preventive Measure: if internet performance is critical, you’ll need to procure adequate

connectivity. While cable internet may be inexpensive, you could be setting yourself up for

frequent jeers from employees. A local DSL operator may offer improved reliability for a

slightly higher cost, but for the most consistent performance, you may find that an expensive

leased line is a requirement for your organization

he management ensures that a plan of a proposed change predicts the

impact and risks to the organisation associated with the change.

Setting up a local network and file sharing in Windows 7

Use the steps in this section to set up a home network using standard RJ-45

hardware and cables. When using steps involving Windows, log in using the main

administrative account. Normally this is the first account that was created when the

computer was first turned on.

Before you begin setting up a local network

Confirm that you have the following hardware and follow these steps:

Network interface card (NIC) or an on-the-motherboard network port for each computer. HP

and Compaq computers are network ready with NICs installed. Confirm the computer has a

RJ-45 network port on the back.

Network hub (or router). A separate network hub may not be necessary if your home is

already equipped with RJ-45 jacks in the walls or if your DSL or cable modem provides RJ-

45 ports (select models). If you need a network hub, consult with a network specialist at your

local computer store to determine a hub that meets your needs.

A crossover cable can be used to connect two computers without a hub. However, it only

allows two computers to connect and is not expandable.

Network cables for each computer.

Disconnect the Internet. If you have a DSL or cable modem, disconnect it.

Disable any firewall software. Firewall software may interfere with network setup. You can

enable the firewall after network setup is complete.

Step 1: Connecting the network hardware and cables to set up a local network

Do the following to set up the network hardware and connect the networking cables.

Set up and turn on the power for the network hub or other networking device. (Follow the

instructions provided by the manufacturer).

Connect the computers to the networking device. If a crossover cable is used, connect the

cable to the RJ45 network ports on each computer.

Connect the computer power cords and turn the computers on.

Make changes to a LAN Time: 120 minutes Activity: Self and Group

Step 2: Turning on Network discovery and file sharing in Windows 7

Turn on Network discovery and file sharing on each computer that you want to access on the

network. Follow these steps to begin setting up the network:

Click Start , and then click Control Panel.

Under Network and Internet, click Choose Homegroup and sharing options.

In the Homegroup settings window, click Change advanced sharing settings.

Turn on network discovery and file and printer sharing. Review the other settings and turn

them on or off.

Click Save changes.

Step 3: Sharing drives, folders, and files in a Windows 7 network

To share non-public folders with other computers on a local network, follow these steps:

Click Start , and then click Computer.

Browse to the folder you want to share.

Right-click the folder, select Share with, and then click Homegroup (Read), Homegroup

(Read/Write), or Specific people.

If you chose Specific people, the File Sharing window displays.

Click the down arrow and select the account you want to share with, and then click Add.

A User Account Control might open. You must accept this Window to make the necessary

changes.

Click an arrow under Permission Level to set the permission level for each account or group.

Step 4: Testing a local network in Windows 7

Open the Windows 7 network window and browse through the shared folders in each

computer on the network. If the computer is able to read and access files from a remote

computer, the remote computer is set up correctly. Browse to every available computer from

each computer on the network. If there are any issues, go back through these steps and

verify that the settings are correct. When all computers are able to network to each other on

the network, continue with the next step to enable Internet access and the firewall.

Step 5: Enabling Internet access and firewall for a local network

Once you have verified that your home network is capable of transferring files, connect and

enable Internet connections for computers with Internet access.

CAUTION:

Make sure that each computer with Internet access is well protected from security threats. At

the minimum, each computer should have its Internet connection protected with a firewall

and Windows should be updated with the latest critical updates from Microsoft Windows

Update. If malicious activity comes though one computer, the activity can quickly spread

through the entire network.

he management ensures that a plan of a proposed change establishes

when the change should occur to minimise the impacts and risks

Accessing shared files and directories in Windows 7

Do the following to access shared files and directories in a local network:

Ensure network discovery and file sharing is turned On.

Click Start , click Control Panel, click Network and Internet, and then click Network and

Sharing Center.

Double-click Network.

The Network window opens and displays computers with shared folders that are detected on

local networks.

Double-click the computer you want to access.

When accessing shared files or directories the following error message window may display:

This error can be caused by the following:

Password Protection is On and the Guest account is On.

The account does not have permission to access the share. This typically occurs when

specific permissions are set up on systems with multiple share folders.

Windows 7 file sharing displays all the shared folders, even those you do not have permission

to access.

To resolve the error, verify the following:

The account has the proper permissions to access the computer.

The computer name and account name are spelled correctly.

Make sure that Firewall software on any connected computer is set to allow access.

he management includes a contingency plan that allows the network to

be restored to a status acceptable to the user in the event of problems

with the change

Contingency planning

The key elements of a contingency plan are “protection, detection, and recoverability.”

A contingency plan acknowledges that disaster can happen: the organization must design a

plan to accommodate the survival of organizational operations in the event of flood, fire,

earthquake, electrical disturbance, or other unexpected events that can disrupt the

organization’s systems. Risk analysis should offer guidance on the likelihood of various

contingencies, and in what resources to invest providing such recovery methods as off-site

systems, backups and so on. Several references discuss contingency planning.

Every effective contingency plan must consider backing up data files.

Most critical to the firm is that a contingency plan:

Exists;

Is communicated to employees; and

Is tested regularly.

The network disaster recovery plan is usually in the form a formal document that is

created by network administrator and other key IT /network management staff.

Depending on the underlying network and organization requirements, it may include

plans and procedures for recovering:

Local area networks (LAN), wide area networks (WAN) and wireless networks

Network-based applications and services

Servers and computer systems

The disaster can be a natural and/or physical disaster, such as flooding or fire, or a

"virtual" disaster in the form of viruses or hacker attacks.

The plan may also include possible threats, network weaknesses and/or

vulnerabilities, which if exploited can result in network outage or degradation and the

procedures to counter them.

esting establishes the success of the installation and of the changes

according to user and organisation requirements.

After installing LAN Speed Test v4, it begins in (Lite) mode. LAN Speed Test (Lite) is

fully functional with no time limits, etc. - only some of the more advanced features

are disabled. LAN Speed Test was designed from the ground up to be a simple but powerful

tool for measuring file transfer, hard drive, USB Drive, and Local Area Network (LAN) speeds

(wired & wireless). First, you pick a folder to test to. This folder can be on a local drive or

USB drive, etc. to test the drive speed, or a shared folder on your network to test your

network speed.

Next, LAN Speed Test builds a file in memory, then transfers it both ways (without effects of

Windows/Mac file caching) while keeping track of the time, and then does the calculations

for you. For more advanced users, you can test to LAN Speed Test Server instead of a shared

folder to take the slower hard drives out of the process as you are testing from one

computer's RAM to another computer's RAM. Simple concept and easy to use. You'll find that

LAN Speed Test will quickly become one of your favourite network tools!

Some of LAN Speed Test v4 features include...

Test the speed of your Local Network by testing to/from network shared folders

Test the speed of your local drives (USB Drives, hard drives, etc.)

Compatible with LST Server (v1.5 or later) for real network performance results

without hard drive limitations – Even test your WAN (Internet) speed with LST Server

Very fast! Most tests are less than 1 minute

Completely Portable - No installation needed

Can be run from a hard drive, USB Flash drives, Network Share, etc.

Compatible with Windows 7 or later and Windows Server 2008 or later

Compatible with Mac 10.7.5 (Lion) or later

LAN Speed Test and LAN Speed Test (Lite) are now the same download

Packets up to 9 GB in size and up to 1000 packets *

Chunk size adjustable up to 1 MB (for advanced testers)

View results by Average, Maximum, and Minimum throughputs *

Progress bar and cancel button allowing user to cancel at any time

Ability to choose Network Interface Card for computers with multiple NICs

Ability to view each packet's results in a chart or by details *

Ability to view results as Gbps, Mbps, Kbps, GBps, MBps, or KBps *

Email results manually, automatically, or only when under a certain speed *

Log results to .csv file with user configurable file location. All entries are SQL

compatible for easy importing into SQL Server, MySql, etc.) *

Option to log Avg, Max, & Min automatically *

View/Edit Log built right into LAN Speed Test *

Network Scan (see other devices on your network, keep notes about them, etc.) *

Run multiple tests automatically - any number of tests from 1 sec to 24 hrs apart *

Open/Save all options and results to .csv file

Command Line Mode - All testing options available from command line *

Command Line Builder (automatically builds the command line options that you need

based on your current settings)

LAN Speed Test's user interface has been greatly improved - Plus it's fully high DPI -

he plan ensures that people affected by the change are notified to

minimise disruption to their activity.

What is Networking and Communication?

Data communications refers to the transmission of this digital data between two or

more computers and a computer network or data network is a telecommunications network

that allows computers to exchange data. The physical connection between networked

computing devices is established using either cable media or wireless media. The best-known

computer network is the Internet.

What are the types of Computer Networks?

In computer networks, the data is passed in the form of packets. The devices that transmit

or receive this data, such as a phone or a computer, are referred to as nodes. There are three

main types of networks:

1. Local Area Network (LAN): It is usually a small network that is restricted to a small

geographic area. A computer network available only to the residents of a building can be

called a LAN.

2. Wide Area Network (WAN): As the name implies, these networks cover a broad range of

geographic area. WANs are used to connect LANs and other types of networks together so

that users and computers can communicate with computers in other regions. An example of

a WAN is the much-used and loved, Internet.

3. Metropolitan Area Network (MAN): MAN is a network that connects the users with

computer resources in a geographic area that is larger than LAN but not quite as large as

What are the basic components of Computer Networks?

1.Servers - Servers are computers that hold shared files, programs, and the network

operating system. Servers provide access to network resources to all the users of the

network. There are many different kinds of servers, and one server can provide several

functions. For example, there are file servers, print servers, mail servers, communication

servers, database servers, print servers, fax servers and web servers, to name a few.

2.Clients - Clients are computers that access and use the network and shared network

resources. Client computers are basically the customers (users) of the network, as they

request and receive services from the servers.

3.Transmission Media - Transmission media are the facilities used to interconnect computers

in a network, such as twisted-pair wire, coaxial cable, and optical fiber cable. Transmission

media are sometimes called channels, links or lines.

4.Shared data - Shared data are data that file servers provide to clients such as data files,

printer access programs and e-mail.

5.Shared printers and other peripherals - Shared printers and peripherals are hardware

resources provided to the users of the network by servers. Resources provided include data

files, printers, software, or any other items used by clients on the network.

6.Network Interface Card - Each computer in a network has a special expansion card called a

network interface card (NIC). The NIC prepares (formats) and sends data, receives data, and

controls data flow between the computer and the network. On the transmit side, the NIC

passes frames of data on to the physical layer, which transmits the data to the physical link.

On the receiver's side, the NIC processes bits received from the physical layer and processes

the message based on its contents.

7.Local Operating System - A local operating system allows personal computers to access

files, print to a local printer, and have and use one or more disk and CD drives that are

located on the computer.

8.Network Operating System - The network operating system is a program that runs on

computers and servers, and allows the computers to communicate over the network.

9.Hub - Hub is a device that splits a network connection into multiple computers. It is like a

distribution center. When a computer request information from a network or a specific

computer, it sends the request to the hub through a cable. The hub will receive the request

and transmit it to the entire network. Each computer in the network should then figure out

whether the broadcast data is for them or not.

10.Switch - Switch is a telecommunication device grouped as one of computer network

components. It uses physical device addresses in each incoming messages so that it can

deliver the message to the right destination or port

You are now ready to go through a check list. Be honest with yourself

Tick the box with either a √ or an X to indicate your response

I am able to maintain the performance of a local area computer network (LAN);

I am able to execute procedures on a LAN;

I am able to administer security, maintain the supply of consumables, and plan

capacity for a LAN;

I am able to maintain the availability of a LAN, and

I am able to manage changes to a LAN

You must think about any point you could not tick. Write this down as a goal.

Decide on a plan of action to achieve these goals. Regularly review these goals.

My Goals and Planning: __________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Support a local area computer network 114043 - geeks4learning

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