2.1 TYPES OF COMPUTER NETWORK MAINTENANCE

PENCEGAHAN

Penyelenggaraan Pencegahan merupakan satu kaedah jangka panjang untuk mempastikan PC sentiasa dalam keadaan baik. Ia merupakan proses yang perlu dilakukan secara berjadual. Terdapat beberapa langkah yang harus dibuat dalam proses penyelenggaraan pencegahan iaitu PC Clean Disk, Disk Defragmenter,\ Membuang Temporary File dan Membuat Windows Update. Clean Disk dilaksanakan bagi membuang fail-fail yang tidak diperlukan yang mengambil ruang di dalam

CPU yang menyebabkan PC perlahan. Disk Defragmenter pula adalah proses penyusunan semula fail-fail di dalam PC dan memperbaiki fail-fail yang rosak. Ia perlu dilaksanakan bagi meningkatkan kadar kelajuan sesebuah PC. Temporary file adalah fail yang wujud apabila kita mencapai laman web di Internet ataupun fail-fail yang wujud apabila tidak disimpan pada sesuatu PC. Fail-fail ini perlu diikeluarkan/padam/hapus untuk menjimatkan ruang pada memori PC. Langkah terakhir PC perlu dibuat Windows Update bagi mendapatkan patches terkini daripada Microsoft. Ini adalah bagi melindungi PC daripada ancaman pihak luar. Sebelum melakukan windows update, pastikan komputer tersebut mempunyai kemudahan internet atau disambungkan kepada rangkaian.

PEMBETULAN

Penyelenggaraan pembetulan adalah kerja yang dilakukan untuk menggantikan sesuatu yang telah rosak. Contohnya mengganti power supply pada komputer, membersihkan kipas pada CPU, menggantikan RAM yang baru untuk menambahkan kapasiti tersebut. Kebanyakan perkhidmatan yang dikehendaki oleh pengguna adalah penyelenggaraan pembetulan.

RAMALAN

Penyelenggaraan ramalan adalah kerja yang dilakukan untuk mengetahui jangka masa sesuatu rangkaian tersebut. Penyelenggaraan ini adalah satu ramalan yang akan terjadi pada masa terdekat.

Network maintenance basically means you have to do what it takes in order to keep a network up and running and it includes a number of tasks:

· Troubleshooting network problems.

· Hardware and software installation/configuration.

· Monitoring and improving network performance.

· Planning for future network growth.

· Creating network documentation and keeping it up-to-date.

· Ensuring compliance with company policies.

· Ensuring compliance with legal regulations.

· Securing the network against all kind of threats.

2.2 COMPANY RESOURCES RELATED TO COMPUTER NETWORK MAINTENANCE

Sumber syarikat yang berkaitan dengan penyelenggaraan rangkaian komputer:

• Bajet – untuk menentukan bajet yang diperlukan pada sebuah syarikat
• Kakitangan mahir – untuk menyelengara dan melahirkan tenaga mahir dalam penyelenggaraan tersebut
• Alat – Syarikat perlulah menyediakan alat peralatan rangkaian bagi pemasangan rangkaian komputer yang perlu diselenggarakan.

Adalah mudah untuk berfikir komputer begitu maju mempunyai masalah yang sama seperti mesin lain. Mereka harus bekerja dengan sempurna setiap masa. Menetapkan mereka sekali, dan mereka hanya bekerja. Yang benar adalah bahawa rangkaian komputer adalah mesin kompleks dan perisian, berkomunikasi secara serentak, menggunakan beratus-ratus bahagian-bahagian dan wayar, dan di bawah serangan yang berterusan oleh keperluan pemprosesan aplikasi, virus yang tidak diingini dan spyware dan mereka sendiri pengguna. Berikut adalah sepuluh sebab-sebab setiap pelayan yang tetap dan proaktif dan penyelenggaraan stesen kerja:

i. Kemas kini keselamatan Microsoft yang kritikal perlu digunakan sekurang-kurangnya sekali sebulan

ii. Firewall, virus dan perlindungan spyware memerlukan kajian dan pengurusan dari masa

iii. Penggunaan harian pelayan dan stesen kerja oleh kakitangan pejabat boleh mewujudkan isu-isu rangkaian.

iv. Pengurusan status sandaran, data yang dipilih dan data ujian adalah penting untuk pemulihan data

v. Server proaktif dan stesen kerja standardisasi mengurangkan masalah Pengurusan sumber cakera keras menghalang isu-isu penyimpanan & kemalangan pelayan

vi. Analisis log peristiwa server boleh mengenal pasti isu-isu sebelum mereka mencipta masalah rangkaian

vii. Pengoptimuman tetap server dan stesen kerja untuk meningkatkan kelajuan dan kecekapan

viii. Penyelenggaraan proaktif memberikan ketenangan sebenar fikiran bahawa seseorang itu kerap menjaga rangkaian anda

ix. Bajet bulanan diramalkan dan sokongan mengurangkan kewangan dan teknikal

2.3 BANDWIDTH MANAGEMENT SOFTWARE

BANDWIDTH

In computer networks, bandwidth is used as a synonym for data transfer rate, the amount of data that can be carried from one point to another in a given time period (usually a second). Network bandwidth is usually expressed in bits per second (bps); modern networks typically have speeds measured in the millions of bits per second (megabits per second, or Mbps) or billions of bits per second (gigabits per second, or Gbps).

Note that bandwidth is not the only factor that affects network performance: There is also packet loss, latency and jitter, all of which degrade network throughput and make a link perform like one with lower bandwidth. A network path usually consists of a succession of links, each with its own bandwidth, so the end-to-end bandwidth is limited to the bandwidth of the lowest speed link (the bottleneck).

Different applications require different bandwidths. An instant messaging conversation might take less than 1,000 bits per second (bps); a voice over IP (VoIP) conversation requires 56 kilobits per second (Kbps) to sound smooth and clear. Standard definition video (480p) works at 1 megabit per second (Mbps), but HD video (720p) wants around 4 Mbps, and HDX (1080p), more than 7 Mbps.

Effective bandwidth -- the highest reliable transmission rate a path can provide -- is measured with a bandwidth test. This rate can be determined by repeatedly measuring the time required for a specific file to leave its point of origin and successfully download at its destination.

BANDWIDHT MANAGER

Software that can prioritize communications by allowing high-priority traffic to use more available bandwidth in the network than lower-priority data. For example, real-time video can be given more bandwidth than file transfers. Large file transfers could be given a lower priority than smaller ones. All of the adjustments are designed to make traffic flow smoothly and avoid congestion.

Bandwidth management is the process of measuring and controlling the communications (traffic, packets) on a network link, to avoid filling the link to capacity or overfilling the link, which would result in network congestion and poor performance of the network. Bandwidth management is measured in bits per second (bit/s) or bytes per second (B/s).

TOOLS AND TECHNIQUES :

1. Packet Sniffer

A packet analyzer (also known as a network analyzer, protocol analyzer or packet sniffer—or, for particular types of networks, an Ethernet sniffer or wireless sniffer) is a computer program or piece of computer hardware that can intercept and log traffic that passes over a digital network or part of a network.^[1] As data streams flow across the network, the sniffer captures each packet and, if needed, decodes the packet's raw data, showing the values of various fields in the packet, and analyzes its content according to the appropriate RFC or other specifications.

Packet capture is the process of intercepting and logging traffic.

2. Network Traffic Measurement

In computer networks, network traffic measurement is the process of measuring the amount and type of traffic on a particular network. This is especially important with regard to effective bandwidth management.

Monitoring network bandwidth is very important for network administrators to rectify the problems that are choking their network bandwidth. Here are 12 free best tools for monitoring network bandwidth. These tools also provide visual representation and graph of how much data is being consumed by the users.

1. Solarwinds

SolarWinds Real-Time Bandwidth Monitor polls your interface as frequently as every half second and reports real-time bandwidth usage on an easy-to-understand graph. Set critical and warning thresholds to instantly see when usage is out of bounds.

2. Wireshark

It is useful in network troubleshooting, development of communication and software protocol, analysis and education. This is a multiplatform application that uses widget toolkit from GTK+ in its latest releases, as well as Qt in development versions to execute its UI and utilizing pcap in packet capturing.

3. Bandwidth Monitor

This application evaluates bandwidth usage on the installed computer. Bandwidth Monitor displays actual download as well as upload speeds both in numerical and graphical forms, registers bandwidth usage, as well as offering weekly, monthly, and daily bandwidth usage reports. This tool evaluates every network connection on computers like LAN network, VPN connection and Internet network.

4. Networx

5. Nuttcp-Cygwin-GUI

6. Cacti

7. Master Shaper

8. BandwidthD

9. PRTG Network Monitor

10. Sarg

11. Squid

12. Internet Bandwidth Monitor (IBM)

2.4 COMPUTER NETWORK MAINTENANCE TIME

DOWNTIME

The term downtime is used to refer to periods when a system is unavailable. Downtime or outage duration refers to a period of time that a system fails to provide or perform its primary function. Reliability, availability, recovery, and unavailability are related concepts. The unavailability is the proportion of a time-span that a system is unavailable or offline. This is usually a result of the system failing to function because of an unplanned event, or because of routine maintenance (a planned event).

The term is commonly applied to networks and servers. The common reasons for unplanned outages are system failures (such as a crash) or communications failures (commonly known as network outage).

The term is also commonly applied in industrial environments in relation to failures in industrial production equipment. Some facilities measure the downtime incurred during a work shift, or during a 12- or 24-hour period. Another common practice is to identify each downtime event as having an operational, electrical or mechanical origin.

The opposite of downtime is uptime.

HOW IT WORKS

Time-based maintenance is performed on a calendar schedule. A maintenance plan for a piece of equipment is put together that needs to be performed regularly. An example is the maintenance that is done on an air-conditioner every year before summer. With the maintenance plan in place, the maintenance is performed each time the calendar rolls over the specified number of days.

2.5 COMPUTER NETWORK MAINTENANCE ANNOUNCEMENT AND TROUBLE TICKET

EXAMPLE

Maintenance Notice

2017/02/04 18:00 (Saturday) - 2017/02/05 12:00 (Sunday) - ITS Maintenance on Feb 4-5, 2017

The following maintenance will be carried out on Feb 4-5, 2017 (this Saturday and Sunday) and among them, the major services to be affected include:

1. Internet service in the Centennial Campus: Saturday 6:00 pm - 8:00 pm

2. Internet service in the Main Campus: Sunday 10:00 am - noon

For enquiries, please contact our Service Desk at ithelp@hku.hk or 3917 0123 during office hours; and call our Computer Room at 2859 2496 after office hours.

Please refer to http://www.its.hku.hk/whats-new/20170127/its-maintenance-window-201702 for details.

We apologize for any inconvenience that may cause.

K C Chang
Systems Team
Information Technology Services

TROUBLE TICKET

A trouble ticket (sometimes called a trouble report) is a mechanism used in an organization to track the detection, reporting, and resolution of some type of problem. Trouble ticketing systems originated in manufacturing as a paper-based reporting system; now most are Web-based and associated with customer relationship management (CRM) environments, such as call centers or e-business Web sites, or with high-level technology environments such as network operations centers (NOCs). A number of companies make software for trouble ticketing, such as NesterSoft's Request Commander. Several other types of software, such as Bluebird include a trouble ticket component.

A trouble ticket is the result of an end user submitting a help request via an issue tracking system, and it typically contains elements detailing the exact nature of the problem the end user is having with a specific network component. The trouble ticket is then forwarded to the appropriate IT technician, who is responsible for addressing the issues within the trouble ticket based on the ticket's severity, impact to the organization, time received, etc.

FUNCTIONALITY

Issue-tracking systems fulfill different functions, in particular:

· Entering of dysfunctions, errors and requests (e.g. manually or by e-mail Response Management Systems)

· Distribution and assignment of issues to persons in charge

· Monitoring of handling, time spent and quality of work

· Ensuring the observation of internal processes by forced control with help of workflows

· Statistical analysis of the number of tickets

· Automatic generation of tickets by alarming systems, e.g. network monitoring

· Fulfillment of external service agreements (Service Level Agreement, SLA)

· Systematic collection of questions and answers for FAQs

· Assignment of a priority to each issue based on the overall importance of that issue, the customer, date of submission, SLA

· Containing a detailed descriptions of the problem being experienced, attempted solutions or workarounds, and other relevant information

· Maintaining of a history of each change

WORKFLOW

An example scenario is presented to demonstrate how a common issue tracking system would work:

1. A customer service technician receives a telephone call, email, or other communication from a customer about a problem. Some applications provide built-in messaging system and automatic error reporting from exception handling blocks.

2. The technician verifies that the problem is real, and not just perceived. The technician will also ensure that enough information about the problem is obtained from the customer. This information generally includes the environment of the customer, when and how the issue occurs, and all other relevant circumstances.

3. The technician creates the issue in the system, entering all relevant data, as provided by the customer.

4. As work is done on that issue, the system is updated with new data by the technician. Any attempt at fixing the problem should be noted in the issue system. Ticket status most likely will be changed from open to pending.

5. After the issue has been fully addressed, it is marked as resolved in the issue tracking system.

If the problem is not fully resolved, the ticket will be reopened once the technician receives new information from the customer. A Run Book Automation process that implements best practices for these workflows and increases IT personnel effectiveness is becoming very common.

2.6 COMPUTER NETWORK MAINTENANCE MANAGEMENT PLAN PREPARATION

You must build processes and procedures for performing your network maintenance tasks; this is called network maintenance planning. Network maintenance planning includes the following:

1. Scheduling maintenance

2. Formalizing change-control procedures

3. Establishing network documentation procedures

4. Establishing effective communication

5. Defining templates/procedures/conventions – standardization.

6. Disaster Recovery.

2.6.1 Scheduled Maintenance

The benefits of scheduled maintenance include the following:

•Network downtime is reduced.

•Long-term maintenance tasks will not be neglected or forgotten.

•Predictable lead times for change requests.

•Disruptive maintenance tasks can be scheduled during assigned maintenance windows, reducing downtime during production hours.

2.6.2 Change Control

•In many companies, change control is formalised and answers the following types of questions:

1. Which types of change require authorisation and who is responsible for authorising them?

2. Which changes have to be done during a maintenance window and which changes can be done immediately?

3. What other actions (such as updating documentation) need to be taken after a successful change?

4. What conditions allow skipping some of the normal change procedures and which elements of the procedures should still be followed?

2.6.3 Network Documentation

Typical elements of network documentation include the following:

1. Network drawings: Diagrams of the physical and logical structure of the network. 2. Connection documentation: Lists of all relevant physical connections, such as patches, connections to service providers, and power circuits.

3. Equipment lists: Lists of all devices, part numbers, serial numbers, installed software versions, (if applicable) software. Licenses, warranty/service information. 4. IP address administration: Lists of the IP subnets scheme and all IP addresses in use.

5. Configurations: A set of all current device configurations or even an archive that contains all previous configurations.

6. Design documentation: This is a document describing the motivation behind certain implementation choices.

2.6.4 Effective Communication

Communication is vital both during troubleshooting and technical support and afterward. During troubleshooting, certain questions must be answered, such as the following:

1. Who is making changes and when?

2. How does the change affect others?

3. What are the results of tests that were done, and what conclusions can be drawn?

2.6.5 Standardization

One of the ways to streamline processes and make sure that tasks are executed in a consistent manner is to define and document procedures; this is called standardization. Defining and using templates is an effective method of network documentation, and it helps in creating a consistent network maintenance process:

1. Are logging and debug time stamps set to local time or coordinated universal time (UTC)?

2. Should access lists end with an explicit "deny any"?

3. In an IP subnet, is the first or the last valid IP address allocated to the local gateway?

2.6.6 Disaster Recovery

The quicker you can replace failed devices and restore functionality, the quicker your network will be running again. To replace a failed device, you need the following items:

1. Replacement hardware.

2. The current software version for the device.

3. The current configuration for the device.

4. The tools to transfer the software and configuration to the device.

5. Licenses (if applicable).

6. Knowledge of the procedures to install software, configurations, and licenses.

Missing any of the listed items severely affects the time it takes to replace the device.

2.7 COMPUTER NETWORK MAINTENANCE JOB ORDER CONTENT

A work order is an order received by an organization from a customer or client, or an order created internally within the organization. A work order may be for products or services.

A "Work Order" sometimes is used in place of an "Invoice" or "Statement" and presented for payment requests.

A work order may be a maintenance or repair request from students, faculty or staff in a university.

Orders received from outside an organization are often dispatched (reviewed and scheduled) before being executed. Work orders may be for preventive maintenance

Contractors may use a single job work order and invoice form that contains the customer information, describes the work performed, lists charges for material and labor, and can be given to the customer as an invoice.

In a service environment, a job order cannot be the equivalent to a work or service order where the job order records the location, date and time the service is carried out and the nature of service that was carried out, the work order does not. The type of personnel (e.g. job position) may also be listed on the job order. A rate (e.g. $/hour, $/week) and also the total amount of hours worked and total value is also shown.

2.8 TECHNICAL WRITING SKILLS

Technical writing is any written form of writing or drafting technical communication used in a variety of technical and occupational fields, such as computer hardware and software, engineering, chemistry, aeronautics, robotics, finance, consumer electronics, and biotechnology. It encompasses the largest sub-field within technical communication.

The Society for Technical Communication defines technical communication as any form of communication that exhibits one or more of the following characteristics:

(1) Communicating about technical or specialized topics, such as computer applications, medical procedures, or environmental regulations;

(2) Communicating through technology, such as web pages, help files, or social media sites; or

(3) Providing instructions about how to do something, regardless of the task's technical nature.

2.8.1 6 Skill Sets Technical Writer Needs to Succeed

Like any profession, becoming a technical writer requires a mastery of certain skill sets. The following is a sampling of what a modern day technical writer needs to bring to the table to be a successful technical communicator.

1. Write clearly, concisely, and precisely. The ability to write well and convey information to the intended audience in an easily understood manner is still the primary prerequisite.

2. Be proficient in using the tools of the trade. Knowing your way around computer systems is a given. You also need to be able to learn quickly and become proficient using computer applications associated with producing your documentation such as Adobe FrameMaker, MS Word, MadCap Flare, RoboHelp, Photoshop, and Illustrator.

3. Be able to select the proper support visuals needed to enhance the written word. To a growing extent, the technical writer needs an appreciation for graphics and formatting as well as illustration skills. For many organizations, the technical writer must collaborate with the subject matter expert (SME) to obtain engineering drawings and the illustrator to design and develop the needed support graphics. Technical writers are often responsible for taking their own photographs too.

4. Have a natural curiosity for exploring things technical and learning how they work. The technical skill of a technical writer depends greatly on the subject matter, product, or service that requires documentation. Most writers expand their knowledge through experience in the profession or by taking specialized technical writing training.

5. Know how to ask questions and learn from the answers. Interacting with SMEs is one the most overlooked skills. You have to be part journalist and part investigative reporter. And, you can’t be too proud to ask the "dumb technical questions" that make engineers do double-takes. When setting up an interview or review, consider the personalities and preferences of your SMEs. Make sure you have all your questions ready up front and that you understand the answers before you leave the meeting. If a follow up is needed, schedule it then.

6. Refine the art of patience and persistence. Unless you have patience, you’ll never make it as a technical communicator. I hate to say it, but most SMEs tend to drag their feet when it comes to a timely turnaround for reviews. It’s a delicate balance, but with a little persistence, they can be trained.

Technical writers and communicators add tremendous value to a documentation project and to the organization that employs them. They make information more useable and accessible to those who need that information, and in doing so, they advance the goals of the organization.