ICT3

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ICT3 Revision

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The needs of an expert user and a novice user

Novice: (have never used the system before) Priority is ease of learning and easy access to help, like to use the mouse, may prefer drop down menus, or click an icon in order to print a file, offer an easy way of undoing an action.

Expert: (have many years experience, know and use all the software functions) These users want to get the job done as quickly as possible, so provide short cut keys to save time from using the mouse & clicking icons etc. such as ctrl = P to print a file.

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Features Suitable for the Disabled User

Sensory Impairment: (such as being unable to read letters on a screen properly) Font size- use an easy to read font, such as arial or tahoma, and that its size is large enough for the users to read, starting at 12pt.

Blind Users: Use a voice synthesiser, where typed words are spoken out by the computer to the user. Use a voice dictation system so the user speaks into a microphone and the computer types the spoken word. also can use braille keyboards to enter data. ability to magnify the screen.

Pysical Impairment: If disability is so severe, use a voice dictation system so the user speaks into a microphone and the computer types the spoken word. Use specialist input devices such as blow pipes to activate controls, or infrared beams.

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Advantages/Disadvantages of Ring Topology

Advantages: Each node has the same access as the others so no one node can hog the network. Peer to peer network, so not dependent on one central server. Faster speeds as data goes in one direction, reducing data collisions.

Disadvantages: Difficult to add/remove devices because there is only one path for the data to follow. Faults are difficult to locate. If communications link or connection fails, the whole system goes down. Similarly, if one node breaks down the whole network fails.

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Advantages/Disadvantages of Star Topology

Advantages: Easy to add/remove devices. Fault tolerant - failure of cable or node should not cause problems for the rest of the network. Load tolerant - data transmission rates are consistent on each link as each node has its own path to the hub.

Disadvantages: Higher cost as it usually requires a large amount of cable, making it a more expensive topology. Dependence on the central hub may be central point of failure - if the device at the centre of the network fails, then the whole network will fail.

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Advantages/Disadvantages of wireless networking

Advantages: Allows inexpensive LANs to be set up without cables. Allows people the freedom of working anywhere a signal can be recieved. Ideal for networks in old listed buildings where the cables would not be allowed to be installed. Global set of standards- you can use wi-fi all over the world. Health and Safety - tidier desktop with no trailing cables.

Disadvantages: Power consumption is high - which means laptops soon exhaust their rechargeable batteries. There may be health problems in using wi-fi. There may be security problems even when encryption is used. Wi-Fi networks may have a very limited range. Can get interference if wireless network signals start to overlap. Transmission speed slower than cable.

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What should a security policy contain?

Why use a security policy: To restrict access to the computer equipment and to restrict access to the storage medium.

It should contain:

  • Physical methods
  • Software security
  • Audit trails
  • Continuous investigation of irregularities
  • System access controls
  • Log-in Procedures
  • Access Rights
  • Firewalls
  • Personnel Administration
  • Operational Procedures
  • Staff code of conduct and responsibilities
  • Disciplinary procedures
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Use of user accounts and logs

User accounts and logs are an important part of network software and prevent misuse of the network by users. Should misuse still occur then it is very easy using this software to determine the culprit.

User Accounts: Everyone whou uses a network is given a user account. This is set up by the network manager. At the time the account is created the network manager will allocate the user certain rights. All users are able to; change their password, change desktop settings and manage their own files in their storage area. it is then up to the person controlling the network to decide; which software the user can access, which shared files the user has access to, if a user is allowed to copy files and if a user is allowed to install software.

User Logs: When a user logs in they supply their username and password. The system then allocates network resources to the user. When a user no longer requires access to the network they can log out. As well as making sure only authorised users are allowed access to the network. the log-in procesure can provide an audit trail as to who has used what resources on the system. This is done by providing a user log, which is a record of the successful and failed log ins and also the resources used by those users who have access to reesources.

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Finding a website using the Internet

Use the URL

Surf the internet by following hyperlinks

Use a search engine

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FTP (File Transfer Protocol)

A standard set of rules providing a way of transferring files over the internet.

Allows any networked computer to manipulate files on another computer on that network.

Advantages: Free software available and relatively easy to use, a common protocol used worldwide, doesn't need a browser, very fast and efficient data transfer, Unlike attaching a file to an e-mail, FTP is not limited in file size.

Disadvantages: Does not need access rights to be set up on remote system, which means it can be used to attack a business' computer system if they are not properly safeguarded, data is transmitted in un-encrpted form including passwords, generally uses command line interface.

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On-line Databases

A major advantage to a company using a network rather than a series of stand-alone computers is that the users are all able to access the same database, thus avoiding having to duplicate data. Because the data is constantly being modified, it will always be up-to-date. Being able to interact with databases is therefore an important service provided by any network. E-commerce systems make use of online databases containing products, customer and order details. Electronic data interchange (EDI), where companies automatically exchange data, is used by large retailers for ordering goods automatically from their suppliers. This system performs ordering, checking and making payments, automatically without requiring any paperwork.

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Distributed Computing

Where a series of computers are networked together and they each work on solving the same problem. Each computer shares data, processing, storage and bandwidth in order to solve a single problem.

Application: Popular Power Project: helping to develop fu vaccines.

Advantages: Reduces cost because an expensive powerful supercomputer is not needed. Can pass work to computers anywhere in the world using the internet. Improved performance as each computer can work on part of the data.

Disadvantages: Issues with security of data spread out on so many different computers. Issues with communications breakdowns.

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Teleworking

Using communications to save a journey, for example, by using videoconferencing to save a journey abroad.

Advantages to the Company: Smaller offices are needed. Fewer backup staff. Staff less likely to have time off work sick. Reduced office overheads. Staff may be happier to work flexible hours. Less office furniture needed. Skilled workers can be retained. Employ workers from a wider range of talent. Comfortable environment can lead to greater productivity.

Disadvantages to the Company: Organisational structure may need to be changed. Hard to check how hard staff are working. More difficult to hold meetings as staff are at home. Hard for managers to manage the work. Employers have to pay for the employees ICT equipment. May be a security risk with ICT equipment distributed accross many homes. Health & Safety checks needed on employees homes.

Continued....

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Teleworking

Advantages to Employee: Can Live anywhere. Environmentally beneficial, reduces traffic congestion ond CO2 emissions as there is no commuting to work, therefore greener. Not having to travel to work saves time. Working hours are flexible. No expenses for travelling to work. Fit work around family commitments. No need to take time off to see workmen. Ideal for disabled people. 

Disadvantages to Employee: Home costs increase. Some employers may pay teleworkers less as there is more competition for jobs. Employees may feel isolated. Boundary between home and work is lost. Other people in the house may disrupt your work. May not be a quiet place in the house to work. Some staff may lose status. No workmates to go out with. May be passed over for promotion.

Benefits to Society: Reduced traffic congestion. Familt relationships improve. Can help sustain rural communities. Fewer greenhouse gas emissions. Less air pollution.

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Code of Conduct

An agreement made by an employee to obey the rules of the organisation and work within specified guidelines as regards use of ICT and the Internet. It also details the sanctions which will be applied should the employ not obey the rules.

It should contain:

  • Responsibilities
  • Respecting rights of others
  • Abiding by current legislation
  • Protecting hardware & software from malicious damage
  • Complying with licencing agreements
  • Permissions on data access
  • Security Policy
  • Authorisation
  • Consequences of breaking the code
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Misuse of ICT facilities and Penalties

Misuse examples;

  • introduction of viruses
  • Using telecommunications for own purposes
  • Using printers for personel use
  • Distribution of material that is ratially or sexually offensive
  • Bullying
  • Inappropriate use of mobile phones
  • Selling to other organisations
  • Violating terms of copyright

Penalties:

  • Informal Warnings
  • Written Warnings
  • Dismissal
  • Prosecution
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Factors that should be considered when creating a

What is a Risk Analysis?: The process of accessing the likelihood of certain events happening and estimating the cost of the damage they could cause and what can be done at reasonable cost to eliminate or minimise the risk.

Identify Potential Risks: viruses, fire, natural damage, hacking, fraud, power failure and gas leaks.

Likelihood of risk occuring

Short and long term consequences of threat: Financial loss due to loss of business through not being able to take orders, loss of integrity means people do not want to deal with the organisation.

The Disaster recovery programme: Ensures the availability of essential resources and computer equipment should disaster occur.

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Ownership and Control over the Internet

The internet is for everybody and no-one owns it. There is little control over the content of the material on the internet, although some governments have started to control what can be seen on it. There is also no control over the people who can access the material on the internet. This means that unless special software is used, children can easily gain access to pornographic or violent images. The lack of policing of the internet also means that the information is not checked to make sure that it is accurate. When you are using the internet you need to be able to check the material for its suitability and accuracy. 

There are a lot of pornographic images/videos on the internet. There are laws covering the production and distribution of this material but as much of this material comes from other countries, where the material is perfectly legal, there is not much that can be done to stop it. The main worry id that young children could access this material. There is special software that is able to filter out this material but it is hard to be completely sure. What is really worrying is that peodephiles use the internet for distributing pornographic pictures of young children and they also lure children into meetings with them after they have spoken to them in chat rooms. You therefore need to be extremely careful arranging any meetings with anyone that you have spoken to on-line.

Continued....

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Ownership and Control over the Internet

Material does not have to be pornographic to be offensive. An image of a pack of hounds attacking a fox may not be offensive to the members of a hunt but could be offensive to animal lovers. Whether material is offensive or not can depend on the person. There is, of course, material that almost everybody would find offensive.

Many countries in the world are not democratic and the people in charge of these countries do not allow free passage of information to and from these countries. They often control the media so that they only allow news which shows the government in a favourable light. Censorship of the internet by government allows them more control on what their people can and cannot view.

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What is a MIS?

An organised collection of people, procedures and resources designed to support the decisions of managers.

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Features of a Good MIS

Accuracy of the Data: The data used from the transaction systems that supply data to the management must be accurate. Flexibility of the Data  Analysis: Different managers have different requirements and the MIS must be able to cope with this. Providing Data in an appropriate form: Managers will need the data to be presented according to their requirments. Some will want it tabulated and others will want trends displayed in graphs and charts. Accessible to a wide range of users: Managers have a wide range of skills and knowledge of ICT systems but MIS needs to be used by all managers. Improves Interpersonel Communications: Amongst managers and employees: managers can get precise information which allows them to communicate this information with managers in other areas. They are also more capable of communicating with subordinates because their decisions are made on sound information. Allows Individual Project Planning: Part of any managers job is to plan for the future. The information from MIS can be used to help plan new developments such as opening new branches, the provision of a new distribution network. Avoids Information Overload: MIS must not produce any superfluous information as this can waste time and can sometimes make essential information harder to use.

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Features of a Poor MIS

  • Complexity of the system
  • Lack of formal methods
  • Inadequate initial analysis
  • Lack of management involvement in the design
  • Inappropriate hardware and software
  • Lack of management knowledge of ICT systems and their capabilities
  • Poor communication between proffesionals
  • Lack of professional standards
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Why Maintenance Procedures are needed?

  • Changes in the way the company operates
  • The rate of VAT could change
  • Changes in income tax
  • Businesses change direction
  • Businesses involved in new ventures
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Types of Maintenance

Perfective: Is maintenance that will improve the performance of the ICT system. Usually this will involve adding features not originally present to the software to make it produce the information from a database faster or to improve the speed of a network.

Adaptive: The way of doing things changes in an organisation. For example, there may be new laws which means that the system needs changing. Changes in the way the organisation operates may require a change in the system.

Corrective: This is correcting faults or bugs that did not reveal themselves during testing. Sometimes the combination of new software and hardware causes the older software to crash. Software manufacturers often produce updates to deal with these issues and these have to be installed.

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What is a Relational Database?

A large collection of data items stored in tables containing links between them so that the data can be accessed in many different ways and by a range of different application programmes.

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Data Warehouse

A huge database dpecifically structured for information access and reporting.

A data warehouse is used to store all an organisations historical data and it is used my MIS' to extract information that will help managers make decisions. The data warehouse is a corporate resource which everyone in the organisation can use provided they have access rights. Examples include:

  • Finding out the day of the week on which a particular store sold the greater number of a certain product in 2006
  • How employee absence due to sickness varied over the last year between the Newcastle branch and the Manchester branch.
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Data Mining

Once the data has been stored in a data warehouse it then needs to be mined to discover; patterns in the data, associations in the data and trends over time. By drilling down into the mass of data, data mining allows users to understand the data more by discovering meaningful patterns in a huge mass of data is possible with the use of data mining software which presents the results in the form of tables and graphs. Data mining can produce data such as; lists of customers likely to buy a certain product, comparisons with competitors, useful what if results from modelling excercises, prediction for future sales, analysis of best sites for shops, sales patterns, customer buying patterns, who is most likely to change their credit card and those customers who are most loyal to the company/product.

Applications: Helping in the fight against terrorism - since 9/11 the US government has been analysing poeple's travel, spending and communication habits using data mining. In order to spot patterns of abnormal behaviour that could lead it to terrorists.

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Data Consistency

When data is held in more than one file it should be stored a in a consistent way.

Because the attributes of any one entity are contained within one file, there is no risk of the same attribute being stored in a different format in a different file Whereas a flat file could store a date as a date/time field in one file and as text in another, making them incompatible.  Also, if the data is changed in one of the files it must also be changed in the other file to ensure consistency.

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Data Redundancy

It refers to the unnecessary duplication of data, where the same data can be duplicated in many files.

In a well designed relational database there should be no repeating attributes (i.e. Fields), no piece of data should be unnecessarily repeated. In a flat-file database details about such information as customer details will be duplicated.  

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Data Integrity

The integrity of data is the correctness of the data, i.e. the extent to which it truthfully represents the original information.

One of the problems of maintaining integrity arises when updating occurs - in a relational database you only have to change data in one table and all other references in any other table will automatically be changed Whereas every record has to be changed in a flat-file database, if one record was left unchanged the data would no longer be wholly correct.  

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Data Independence

The data and the applications which use it are separate.

Provided that new fields are not created, the structure of the database can be changed without affecting the applications which process it.

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Factors which influence the choice of a network

  • Cost of network
  • Size of organisation
  • How the system will be used
  • Existing Systems
  • Performance Required
  • Security Issues
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Facilities needed for an E-commerce System

Trained staff to create and maintain the website: Creating good e-commerce and updating the site with new products, new prices, new features etc. requires expertise and design skills.

An electronic catelogue/database of stock: The database of stock with a user interface that provides the user with information about products, prices, etc.

Using the search facility the cutomer can go straight to the product they are interested in or they can just browse.

Methods of secure payment/shopping trolley: Customers must be able to add goods to their trolley and then go to the on-line checkout to pay for them. Credit and debit card details need to be kept secure when transmitted over the internet and encrption is used to ensure that hackers cannot access this information.

Database of customer orders: This database keeps details on what customers have ordered and is used in case goods need to be returned. It can also be used for repeat orders so the customer does not have to enter all their details in again, thus saving time. 

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Changeover Strategies

Direct Changeover:

Method user stops old system one day and starts the new one the next day

+Adv requires fewer resources & is easy to do provided nothing goes wrong

-Disadv risky if new system is cutting edge & not tried out; if system fails then could ruin the business

Parallel Changeover


Method run old and new together for a few weeks or months using the same data. If results match, and users are happy with it, then new system can be implemented.


+Adv reduces risk if system is brand new. Old system is then abandoned

-Disadv Cannot be used if there is no existing system; requires more planning; expensive in people’s time as work is being done twice

Continued ....

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Changeover Strategies

Phased Conversion

Method system broken down into modules and implemented a module at a time until whole system is transferred

+Adv allows problems to be solved before moving on to next module

-Disadv only suitable for systems consisting of separate modules

Pilot Conversion


Method ideal for large organisations with lots of branches as new system used only by one branch and then transferred to other branches over time

+Adv implementation is on a much smaller and manageable scale

-Disadv takes longer to implement the system in all branches

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Users will become dissatisfied because...

  •     The full range of user requirements has not been met so system does not live up to user expectations.
  •      Change in business needs may mean current system cannot deal with the new demands placed on it.
  •      System fails to supply users with the information they require. 
  •       User interface causes users problems, meaning they have to contact the help desk more often.
  •      Cost of user support is too high.
  • System may crash regularly owing to lack of testing

   

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Factors of HCI

  • Consistency of signposting and pop-up information
  • On-screen help
  • Layout appropriate task
  • Differentiation in user expertise
  • Clear navigational structure
  • Use by disabled people
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Data Normalisation

A staged process which removes repeated groups of data and inconsistencies.

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Consequences of Change: Skills

New ICT systems need new skills and staff must be prepared to learn these skills. Old skills may not be needed, so it is necessary for staff to go on courses to ensure that they do not become unemployable. When new systems are introduced, staff will need to be trained to use the new system. The increased use of ICT usually means that there is an increase in the number of skilled jobs available, usually at the expense of less skilled jobs. There are a number of jobs and skills that have now disappeared and these include:

  • Typist - most people word-process their own documents
  • Filing Clerk - data is now stored on computers in databases.
  • Internal post clerk - these people delivered internal mail. Most internal mail makes use of e-mail now
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Consequences of Change: Work Patterns

With the increased use of computers and communications, many organisations now operate in global markets and have to be able to react to customers' requests. This necessitates some operations having to run 24 hours a day. Flexibility can mean that more part time work, and work outside normal office hours is also available. This will suit some people such as mothers with young children but others may not get time off at the same time as their partner.

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Moral Issues associated with the Internet

Deliberately setting up websites containing incorrect information: People may rely on and use this information thinking its correct.

Bullying: In chat rooms, by e-mail, in blogs, by text message is a problem especially for the young.

Inappropriate Websites: People are able to view inappropriate material such as ***********, racism, violent videos, how to make explosives etc.

Using e-mails to give bad news when explaining face-to-face would have been better.

Spreading Rumours: It is easy to spread rumours using the internet. You only have to tell a few people in a chat room and the rumour will soon spread. Normally, if someone started a rumour that was untrue and it caused another person distress, then the person starting the rumour could be sued. When rumours are started over the internet it is difficult to identify the person responsible.

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Ethical Issues associated with the Internet

Plagiarism: Copying material without attributing or referencing the source of the information. This could also involve using websites which sell essays or coursework.

Sending spam: People waste time deleting spam if the spam filter allows it through.

Companies monitoring staff use of the internet and e-mail. Some organisations will even read personel e-mails.

Using someone's wireless internet connection without Permission. Sometimes it is possible to connect to the internet using an open network. The net result of using the network is to slow the network down for legitimate users.

Using photo editing software to distort reality: By using photo/video editing software you can distort reality and you can no longer believe what you see in video, TV, newspapers, magazines and on websites.

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Social Issues associated with the Internet

Privacy Issues: Social networking sites, e-commerce sites, internet service provider records, e-mail monitoring at work, etc. all erode a users privacy.

Gambling Addiction: Gambling can cause many social problems and it is on the rise with the ease with bets can be made using the internet.

Obesity: Many activities in the past involved physical excercise which kept people healthy. Use of the internet for long periods of time is not a healthy activity.

Addiction to computer games: Many children spend hours playing computer games and their social skills and school work can suffer as a result.

Widens the gaps between the haves and have nots: Internet access widens the gap between rich and poor countries and individuals.

Organisations moving call centres abroad: Because the wage bill is less and the same service can be provided cheaply using the internet and internet phone links.

The growth of e-commerce may mean shops have to close, leaving some city centres looking desolate.

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Distributed Databases

A distributed database has data stored on a number of computers at different locations but appears as one logical database.

Advantages: Reduce dependence on one central huge store of data, Reduces network traffic as local queries can be performed using the data on the local server, Faster reponse to user queries of the database, Easy to backup and copy data from one server to another and if one server fails then the other servers can be used.

Disadvantages: Heavy reliance on networks and communications which may not always be reliable, Local databases may be amended or used incorrectly leading to greater chance of data inconsistency, Security may be problematic particularly if sensitive personel data is being transferred, If one of the links to a server failed then the data could not be obtained from that server, Increased costs owing to the use of expensive communication lines and Harder to control the security of data spread in many different locations.

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Client-Server Network

A network where several computers are connected to one or more servers, where processing and resources are shared....preferred choice for large organisations.

Advantages: Security is better because it is controlled centrally on the server, and a person is given responsibility for it. The server is the central backing store for all data, meaning all users can access to the same set of data. All the administration of the network, such as allocation of user names, passwords, help, etc. is performed centrally so users do not have to worry about them.

Disadvantages: More expensive than peer-to-peer as servers are expensive. All users are reliant on server, but the network is unusable if the server breaks down until it can be repaired. Requires specialist knowledge to operate, need to have a person who understands the technicalities of a network in charge of the network - known as the network manager.

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Peer-to-Peer Network

A small network where each computer has the same status, processing is local on a single PC, resources are shared.

Advantages: Cost saving, as no server is needed, so all the computers can be the same. No network manager is needed, as all users take responsibility for the network. Easy to set up as they are the simplest of computer networks and can be set up by anyone.

Disadvantages: Poorer security as resources are shared, so users have to decide what resources of theirs can be used by other users on the network. Users need more IT knowledge as they will be responsible for the files on their own computers. Users may find it difficult to find files, as these will not be organised and held centrally.

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Feasibility Report

The feasibility study is an initial investigation to look at the likelihood of ceing able to create a new system.

Should include;

  • Statement of purpose of the system
  • Definition od system scope so that everyone is clear what the system does, and also what it does not do.
  • Details of existing hardware and software
  • Major data processing funstions and processes
  • List of problems of current system
  • Costs & Benefits of development costs will be incurred such as staff, equipment, software, training, etc.
  • Conclusion & Recommendations
  • May be a draft plan for the implementation project
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Included in a Disaster Recovery Programme

The plan will cover;

  • the total or partial loss of computing equipment
  • the loss of essential services such as electricity, heating or air conditioning
  • the loss of certain key employees
  • the loss of maintenance or support services
  • the loss of data or software
  • the complete or partial loss of telecommunications equipment or services
  • the complete or partial loss of the premises housing the IT equipment
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Comments

Simon Buchanan

thank you so much just what i was looking for! is there an AS one because that would be great!

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