Networks Unit 1 - Computer Systems St Kentigern’s Academy

NetworksNetworks

Unit 1 - Computer SystemsUnit 1 - Computer Systems

St Kentigern’s AcademySt Kentigern’s Academy

What I need to know…What I need to know… Comparison of LANs, WANs, Intranet and Internet work in Comparison of LANs, WANs, Intranet and Internet work in

terms of transmission media, bandwidth, geographical spread terms of transmission media, bandwidth, geographical spread and functions;and functions;

Distinction between a mainframe with terminals and a network Distinction between a mainframe with terminals and a network

of computers; of computers;

Descriptive comparison of peer-to-peer networks and client Descriptive comparison of peer-to-peer networks and client server networks;server networks;

Description of the functions of file, print and web servers;Description of the functions of file, print and web servers; Description of a node and a channel; Description of a node and a channel;

Description of bus, star, ring and mesh topologies using the Description of bus, star, ring and mesh topologies using the terms node and channel;terms node and channel;

What I need to know…What I need to know…

Description of the consequences for each of the Description of the consequences for each of the above topologies of node and channel failure;above topologies of node and channel failure;

Simple description of the functions and uses of a Simple description of the functions and uses of a

hub, switch and router;hub, switch and router; Identification of the need for a network interface Identification of the need for a network interface

card (NIC);card (NIC);

Description and explanation of the trends towards Description and explanation of the trends towards higher bandwidth and wireless communications;higher bandwidth and wireless communications;

What I need to know…What I need to know…

Description of the following technical reasons for the Description of the following technical reasons for the increasingly widespread use of networks: increasingly widespread use of networks: advances in computer hardware, including processors, main advances in computer hardware, including processors, main

memory capacity, backing storage, data transfer rates memory capacity, backing storage, data transfer rates improved network related software, including browsers and improved network related software, including browsers and

network operating systems;network operating systems;

Description of the misuse of networks for the Description of the misuse of networks for the following illegal purposes: breaching copyright, following illegal purposes: breaching copyright, hacking and planting viruses;hacking and planting viruses;

Description of the application of the Computer Description of the application of the Computer

Misuse Act, the Copyright Designs and Patents Act Misuse Act, the Copyright Designs and Patents Act and the Data Protection Act to the misuse of and the Data Protection Act to the misuse of networks.networks.

What you already knowWhat you already know

A A networknetwork is defined as an is defined as an interconnected set of independent interconnected set of independent computers connected by a computers connected by a communication channel.communication channel.

Networks are used to transmit and Networks are used to transmit and share data as well as enable share data as well as enable communications.communications.

What you already knowWhat you already know

TerminalsTerminals are composed of a monitor are composed of a monitor and keyboard with little or no local and keyboard with little or no local storage or processing power which serve storage or processing power which serve as access points to the as access points to the storage/processing capabilities of a storage/processing capabilities of a mainframe.mainframe.

What you already knowWhat you already know Mainframes Mainframes are powerful computer systems which are powerful computer systems which

are designed to provide:are designed to provide:

High capacity I/O capability;High capacity I/O capability;

High speed processing;High speed processing;

Centralized storage and processing;Centralized storage and processing;

Reliability and security; Reliability and security;

High availability; &High availability; &

Thorough backup and recovery.Thorough backup and recovery.

Mainframes v’s NetworkMainframes v’s Network

Mainframe computer Mainframe computer with terminalswith terminals

Network of computers Network of computers (client-server)(client-server)

User terminals are User terminals are ‘dumb’- they do not have ‘dumb’- they do not have any processing powerany processing power

Each network client Each network client machine has its own machine has its own processorprocessor

All processing is done All processing is done centrally in the centrally in the mainframe, which is a mainframe, which is a multi-processor machinemulti-processor machine

Processing is done on the Processing is done on the network clientsnetwork clients

Multi-userMulti-user Single userSingle user

Local Area NetworkLocal Area Network

Functions:Functions: Include sharing data files, sharing Include sharing data files, sharing

peripherals, communications.peripherals, communications.

Geographical Spread:Geographical Spread: Confined to a limited geographical area, Confined to a limited geographical area,

usually a room, department or a college usually a room, department or a college campus.campus.

Local Area NetworkLocal Area Network

Transmission Media:Transmission Media: Either cable or wireless (WLAN). One Either cable or wireless (WLAN). One

characteristic of the transmission media is characteristic of the transmission media is that it is owned by the organization who that it is owned by the organization who owns the LAN. Cable is typically CAT(egory) owns the LAN. Cable is typically CAT(egory) 5 copper wire or fibre-optic cable.5 copper wire or fibre-optic cable.

BandwidthBandwidth A high bandwidth, e.g. 100-1000 Mbps. A high bandwidth, e.g. 100-1000 Mbps.

This bandwidth is available for both This bandwidth is available for both sending and receiving data.sending and receiving data.

Wide Area NetworkWide Area Network

Functions:Functions: Include sharing data files, email and Include sharing data files, email and

video conferencing. WANs are not used video conferencing. WANs are not used for peripheral sharing.for peripheral sharing.

Geographical Spread:Geographical Spread: No physical limitations.No physical limitations.

Wide Area NetworkWide Area Network

Transmission Media:Transmission Media: Any combination of copper cable, optical Any combination of copper cable, optical

fibre and wireless. The transmission fibre and wireless. The transmission media is owned by many different media is owned by many different organizations.organizations.

BandwidthBandwidth

A low bandwidth compared to a WAN. A low bandwidth compared to a WAN.

IntranetIntranet Functions:Functions:

To share company information and computing To share company information and computing resources among employees. Can also be resources among employees. Can also be used for group work and for teleconferences.used for group work and for teleconferences.

Geographical Spread:Geographical Spread: A private network belonging to a company or A private network belonging to a company or

organization, for internal use only, although it organization, for internal use only, although it may be geographically widespread. An may be geographically widespread. An Intranet uses normal Internet protocols, web Intranet uses normal Internet protocols, web browsers, HTML and in general looks like a browsers, HTML and in general looks like a private version of the Internetprivate version of the Internet

IntranetIntranet

Transmission media:Transmission media: Use the same as WAN’sUse the same as WAN’s

Bandwidth:Bandwidth: Variable depending upon the situation. Variable depending upon the situation.

Bandwidth will be high on a LAN which is Bandwidth will be high on a LAN which is part of an Intranet, but when data is being part of an Intranet, but when data is being sent via the Internet, then bandwidth will be sent via the Internet, then bandwidth will be much lower.much lower.

InternetworkInternetwork Functions:Functions:

An internetwork consists of two or more LANs. An internetwork consists of two or more LANs. The networks are connected by devices such as The networks are connected by devices such as routers or switches in such a manner that all of routers or switches in such a manner that all of the users and devices can communicate. An the users and devices can communicate. An Internetwork functions as a single network, e.g. Internetwork functions as a single network, e.g. the internetthe internet

Geographical Spread:Geographical Spread: Could be used to link several LAN’s in the same Could be used to link several LAN’s in the same

complex or it could link networks across a complex or it could link networks across a city/country/the world.city/country/the world.

InternetworkInternetwork

Transmission Media:Transmission Media: If it is linking several LAN’s in the same If it is linking several LAN’s in the same

geographical location it will probably use geographical location it will probably use fibre-optic. fibre-optic.

If is is linking over a wide geographical If is is linking over a wide geographical area it will use a form of broadband. area it will use a form of broadband.

It may also be wireless.It may also be wireless.

Bandwidth:Bandwidth: Will be variable, the same as the intranetWill be variable, the same as the intranet

Network topologiesNetwork topologies

A A topologytopology refers to the structure of a refers to the structure of a network: the way in which the interconnection network: the way in which the interconnection between the terminals/workstations/nodes on between the terminals/workstations/nodes on the network is organized.the network is organized.

A A nodenode is any device attached to a network. is any device attached to a network.

A A channelchannel is a path over which data is is a path over which data is transmitted between one computer and transmitted between one computer and another.another.

Network topologiesNetwork topologies

LAN topologies are:LAN topologies are: Bus Topology;Bus Topology; Ring Topology; &Ring Topology; & Star Topology.Star Topology.

Wan topology is:Wan topology is: Mesh Topology.Mesh Topology.

Bus topologiesBus topologies

node channel

T T


All nodes are connected to a main All nodes are connected to a main communications channel, the bus;communications channel, the bus;

Workstations broadcast their signal to Workstations broadcast their signal to all nodes on the network; &all nodes on the network; &


Each node recognizes and accepts only Each node recognizes and accepts only its own message.its own message.

This is done by a device called a This is done by a device called a terminator at each end to catch stray terminator at each end to catch stray signals and prevent them from signals and prevent them from interfering with other signals on the interfering with other signals on the bus.bus.


AdvantagesAdvantages: : If one of the nodes on a bus network fails, If one of the nodes on a bus network fails,

then it has no effect on the rest of the then it has no effect on the rest of the network;network;

Easy to add new nodes.Easy to add new nodes.

DisadvantagesDisadvantages: : If the channel is faulty, then the network If the channel is faulty, then the network

is unable to operate;is unable to operate; Nodes may have to compete with each Nodes may have to compete with each

other to transmit and receive data.other to transmit and receive data.

Ring topologiesRing topologies

node channel


Each of the nodes is connected to a Each of the nodes is connected to a single channel whose ends are joined to single channel whose ends are joined to form a circle.form a circle.

Data travels round the channel in Data travels round the channel in packets in one direction only, each packets in one direction only, each node passing them to the next until it node passing them to the next until it reaches the receiving node which reaches the receiving node which accepts the data.accepts the data.


AdvantagesAdvantages rings support high data transfer rates; rings support high data transfer rates; they are very stable when under pressure.they are very stable when under pressure.

DisadvantagesDisadvantages they can be expensive to install because of they can be expensive to install because of

the electronics; the electronics; failure of one node can lead to the network failure of one node can lead to the network

crashing unless a bypass installed; crashing unless a bypass installed; a break in the channel crashes network.a break in the channel crashes network.

Star topologiesStar topologies

Centralnode

node

Channel


•All nodes are connected by their own individual channels to one central device called the central node.

•When a node transmits a signal to the network it goes to the hub or central node which then broadcasts it to the other nodes.

•This topology can be used to connect LAN’s to each other to form an internetwork.


•Advantages

•a node or channel failure will not disable the entire network;

•Very easy to expand.

•Disadvantages

•cabling costs are high;

•can become congested at the central node;

•if central node fails then the network goes down.

Mesh topologiesMesh topologies

channel

node


•Mesh topology has multiple channels between nodes on the network.

•Data can be sent through one of several routes through the network.

•If every node is directly connected to every other node it is known as a fully connected mesh.

•A fully connected mesh network provides the greatest possible protection against failure of a single communication channel since there are many alternative routes for the data to take.


•Advantages•failure of a node or channel does not disrupt network traffic. •Transmission bottlenecks are avoided because of alternative channels.

•Disadvantages •additional burdens in terms of cabling and maintenance of the network

Network Interface CardsNetwork Interface Cards

A A network interface cardnetwork interface card, or NIC is a small circuit , or NIC is a small circuit board that is fitted inside a computer system to board that is fitted inside a computer system to allow it to communicate with a computer network.allow it to communicate with a computer network.

In addition to a network interface card, some In addition to a network interface card, some computers have a computers have a wireless network interface wireless network interface card which allows them to communicate with other card which allows them to communicate with other computers on a local area network from anywhere computers on a local area network from anywhere in the immediate vicinity of a in the immediate vicinity of a wireless base station.wireless base station.

WiFi WiFi is one current standard of wireless networking.is one current standard of wireless networking.

Peer-to-Peer NetworksPeer-to-Peer Networks

This is a network in which the This is a network in which the computers are managed computers are managed independently of each other and independently of each other and have equal status when it comes to have equal status when it comes to communicating with each other, communicating with each other, sharing resources like data files and sharing resources like data files and peripherals, or carrying out key peripherals, or carrying out key operations such as validating users.operations such as validating users.


Sharing resourcesSharing resources Each workstation can make its resources Each workstation can make its resources

available to the other resources available available to the other resources available to the other workstations on the network.to the other workstations on the network.

The resources could be a hard disk, a cd-The resources could be a hard disk, a cd-rom, a printer or data files.rom, a printer or data files.

A shared resource simply appears as A shared resource simply appears as another device connected to the station another device connected to the station and the user accesses the resource and the user accesses the resource transparantly.transparantly.


Sharing resourcesSharing resources Each workstation can make its resources Each workstation can make its resources

available to the other resources available available to the other resources available to the other workstations on the network.to the other workstations on the network.

The resources could be a hard disk, a cd-The resources could be a hard disk, a cd-rom, a printer or data files.rom, a printer or data files.

A shared resource simply appears as A shared resource simply appears as another device connected to the station another device connected to the station and the user accesses the resource and the user accesses the resource transparantly.transparantly.


Centralised StorageCentralised Storage There is none.There is none.

Back-up regimeBack-up regime Because of no centralised storage each Because of no centralised storage each

workstation must be backed up workstation must be backed up individually.individually.


SecuritySecurity Is difficult to implement because there is Is difficult to implement because there is

no mechanism for centrally managing no mechanism for centrally managing acccess to the network.acccess to the network.

Individual workstations can set up id’s Individual workstations can set up id’s and passwords.and passwords.

EnvironmentEnvironment Best suited to a trusting environment – Best suited to a trusting environment –

home!home!

Client-Server NetworksClient-Server Networks

Is composed of a client and a server.Is composed of a client and a server. The client is a workstation operated by a The client is a workstation operated by a

user;user; The server is a computer which controls a The server is a computer which controls a

resource which it makes available to resource which it makes available to clients on the network.clients on the network.

Examples of resources are:Examples of resources are: Data files, printers, applications, access Data files, printers, applications, access

to web pagesto web pages


Sharing ResourcesSharing Resources All resources on the network are All resources on the network are

managed by the servers which provide managed by the servers which provide clients with access to resources.clients with access to resources.

Centralised StorageCentralised Storage Data is normally stored on central Data is normally stored on central

storage attached to a file serverstorage attached to a file server


Back-up RegimeBack-up Regime Centralised storage means that a rigorous Centralised storage means that a rigorous

backup regime can be organised with regular backup regime can be organised with regular backups being made each day from the file backups being made each day from the file server.server.

SecuritySecurity A server holding a database of user info that A server holding a database of user info that

contains id’s, passwords and access rights is contains id’s, passwords and access rights is normally given the task of implementing the normally given the task of implementing the security on the network.security on the network.


EnvironmentsEnvironments Used in businesses and organisations.Used in businesses and organisations.

Peer-to-Peer v’s Client-Peer-to-Peer v’s Client-ServerServer

Advantages of client-server networks:Advantages of client-server networks: Increased security over peer-to-peer – each user must log in to Increased security over peer-to-peer – each user must log in to

serverserver

Different users can be given different levels of access to data.Different users can be given different levels of access to data.

Resources are controlled through the serverResources are controlled through the server

Workgroup computing – many users can work on the same Workgroup computing – many users can work on the same document simultaneously.document simultaneously.

Flexible use of stations – any user can log into the file server Flexible use of stations – any user can log into the file server and can access their own data from any station.and can access their own data from any station.

Backup is done centrally – the system administrator is Backup is done centrally – the system administrator is responsible for making backup copies of all the data on the file responsible for making backup copies of all the data on the file server.server.


Disadvantages of client-server networks:Disadvantages of client-server networks: If the file server is not working then users cannot If the file server is not working then users cannot

access their data.access their data.

Client-server is more expensive than peer-to-peer – Client-server is more expensive than peer-to-peer – it is necessary to buy a server and server software.it is necessary to buy a server and server software.

Advantages of peer-to-peer networks:Advantages of peer-to-peer networks: Each station on a peer to peer network has a Each station on a peer to peer network has a

similar status, with its own local storage similar status, with its own local storage devices.devices.

Cheaper than client/server – no need for file Cheaper than client/server – no need for file server software.server software.

Easier to set up current operating systems for Easier to set up current operating systems for peer-to-peer operations, for example, Windows peer-to-peer operations, for example, Windows XP.XP.


Disadvantages of peer-to-peer Disadvantages of peer-to-peer networksnetworks:: No central file storage – users must always use No central file storage – users must always use

the same machine to access their own data.the same machine to access their own data.

Users must backup their own data.Users must backup their own data.

If one station is switched off, it may not be If one station is switched off, it may not be possible to access some resources.possible to access some resources.

Peer-to-peer is less secure than client/server - Peer-to-peer is less secure than client/server - users may not be required to login.users may not be required to login.


Hubs, Switches and Hubs, Switches and routersrouters

Whatever type of transmission Whatever type of transmission medium or topology is chosen for a medium or topology is chosen for a network, there must be some means network, there must be some means of connecting the workstations.of connecting the workstations.

Hubs switches and routers are all Hubs switches and routers are all devices which allow workstations to be devices which allow workstations to be connected and so create a network connected and so create a network topology.topology.

HubsHubs A A repeater repeater is a device which boosts a signal is a device which boosts a signal

on a cable. on a cable. A repeater has two ports, or connections, one A repeater has two ports, or connections, one

for the input signal and one for the output.for the input signal and one for the output.

Repeater

HubsHubs

A hub works in the same manner as a A hub works in the same manner as a repeater, except that a hub has multiple repeater, except that a hub has multiple ports, allowing more than one device to ports, allowing more than one device to share the wire.share the wire.

Hub

Each workstation which is connected to a hub Each workstation which is connected to a hub may be up to 100 meters away.may be up to 100 meters away.

A hub is a shared device- only one station A hub is a shared device- only one station ‘speaks’ at a time. All connected stations hear ‘speaks’ at a time. All connected stations hear the broadcast, even if it isn’t meant for them.the broadcast, even if it isn’t meant for them.

This places unnecessary traffic on the This places unnecessary traffic on the network, causing collisions which slow the network, causing collisions which slow the network down.network down.

HubsHubs

SwitchSwitch A switch operates like a ‘smart’ hub.A switch operates like a ‘smart’ hub.

A switch divides a network into segments, one A switch divides a network into segments, one segment for each connected machine.segment for each connected machine.

More than one machine can speak at once and More than one machine can speak at once and only the intended recipients receive the data only the intended recipients receive the data signal.signal.

Workstations which are connected via a switch Workstations which are connected via a switch benefit because there are no collisions between benefit because there are no collisions between signals to reduce the speed of the network. signals to reduce the speed of the network.

RouterRouter

A router is a device which links two or A router is a device which links two or more networks.more networks.

The function of the router is to look at The function of the router is to look at the destination addresses of the the destination addresses of the packets of data passing through it, packets of data passing through it, and decide which route each packet and decide which route each packet should take.should take.

File, Print and Web File, Print and Web ServersServers

Function of a File ServerFunction of a File Server This server provides central disk This server provides central disk

storage for user’s programs and data storage for user’s programs and data on a networkon a network

File server software is also requiredFile server software is also required The software’s function is to organise The software’s function is to organise

the storage of user data and handle the the storage of user data and handle the security of the networksecurity of the network

Functions of a Print Functions of a Print ServerServer

A print server or printer server allows A print server or printer server allows all of the client stations to use a all of the client stations to use a printer controlled by it.printer controlled by it.

A printer server provides a queuing A printer server provides a queuing facility which allows users to receive facility which allows users to receive their printouts in turn, or it may be their printouts in turn, or it may be programmed to give priority to programmed to give priority to particular users.particular users.

Functions of a Web Functions of a Web ServerServer

A web server is a computer that A web server is a computer that provides World Wide Web services provides World Wide Web services to a network. to a network.

The term web server may also be The term web server may also be used to refer only to the software. used to refer only to the software.

Trends towards higher Trends towards higher bandwidths and wireless bandwidths and wireless

communicationcommunication

Higher BandwidthHigher Bandwidth Bandwidth is the measurement of the Bandwidth is the measurement of the

quantity of data which may be carried quantity of data which may be carried by a communication channel at one by a communication channel at one time.time.

A current Ethernet LAN has a A current Ethernet LAN has a bandwidth of 1000Mbps.bandwidth of 1000Mbps.

A current fileserver may have 1000 Mbps (Gigabit) bandwidth A current fileserver may have 1000 Mbps (Gigabit) bandwidth connection to a local area network. connection to a local area network.

New desktop computers and laptops now have Gigabit network New desktop computers and laptops now have Gigabit network interface cards.interface cards. Such bandwidths can download a DVD-quality, full-length Such bandwidths can download a DVD-quality, full-length

Hollywood movie as quickly as 30 seconds, depending on network Hollywood movie as quickly as 30 seconds, depending on network conditions, compared with several hours over a typical Internet conditions, compared with several hours over a typical Internet broadband connection.broadband connection.

Basic home broadband using ADSL has a bandwidth of 512 Basic home broadband using ADSL has a bandwidth of 512 Kbps, although 1 Mbps and 2 Mbps have now become standardKbps, although 1 Mbps and 2 Mbps have now become standard N.B. there are physical limits to current ASDL technology, mainly N.B. there are physical limits to current ASDL technology, mainly

due to the distance between the subscriber and the local telephone due to the distance between the subscriber and the local telephone exchange. Also, domestic ADSL is subject to a contention ratio- exchange. Also, domestic ADSL is subject to a contention ratio- which means that each line is shared by a number of other users, which means that each line is shared by a number of other users, e.g. 25-50.e.g. 25-50.


communicationcommunication


communicationcommunicationWireless CommunicationWireless Communication More devices are having wireless More devices are having wireless

functions incorporated as standard. functions incorporated as standard. Most laptop computers are fitted with Most laptop computers are fitted with wireless network interface cards in wireless network interface cards in order to access networks without a order to access networks without a physical connection.physical connection.

We discussed a number of these We discussed a number of these technologies in the last section.technologies in the last section.

Technical reasons for the increasingly Technical reasons for the increasingly widespread use of networkswidespread use of networks

Advances in computer hardwareAdvances in computer hardware

ProcessorsProcessors have become faster, and one have become faster, and one trend is to increase the number of trend is to increase the number of processors on a single chip or in one processors on a single chip or in one computer system in order to improve computer system in order to improve system performancesystem performance

Main memory capacity Main memory capacity has tended to has tended to increase as the cost of RAM chips continues increase as the cost of RAM chips continues to fall. This has allowed the development to fall. This has allowed the development and implementation of larger, more and implementation of larger, more complex complex network operating systems network operating systems software.software.


Backing storage Backing storage capacity has increased as capacity has increased as the cost of hard disk storage falls and new the cost of hard disk storage falls and new types of storage media, such as Blu-ray, are types of storage media, such as Blu-ray, are introduced. Large capacity hard disk drives introduced. Large capacity hard disk drives make it possible to store the data from make it possible to store the data from many networks users on one file server. many networks users on one file server.

Data transfer rates Data transfer rates are also increasing, are also increasing, for instance, 10 Mbps Ethernet is being for instance, 10 Mbps Ethernet is being replaced by 100 Mbps. This improvement in replaced by 100 Mbps. This improvement in bandwidth allows larger files to be bandwidth allows larger files to be transferred in less time.transferred in less time.

Technical reasons for the increasingly Technical reasons for the increasingly widespread use of networks widespread use of networks

Improved network related softwareImproved network related software

Browser softwareBrowser software over the past few years has been the ability of over the past few years has been the ability of

modern browsers to have their functionality modern browsers to have their functionality extended by the addition of various plug-ins. extended by the addition of various plug-ins.

Plug-ins allow browsers to display different types Plug-ins allow browsers to display different types of data other than plain HTML pages, such as of data other than plain HTML pages, such as animated graphics, sequences and streamed animated graphics, sequences and streamed video. video. Some examples of plug-ins are Flash, Shockwave. Some examples of plug-ins are Flash, Shockwave.

RealPlayer, Acrobat, QuickTime and Cortona.RealPlayer, Acrobat, QuickTime and Cortona.


A network operating systemA network operating system controls all controls all of the devices on a network so that resources of the devices on a network so that resources can be shared efficiently and files can be can be shared efficiently and files can be transferred. It handles the administration of transferred. It handles the administration of all network functions. all network functions.

Network operating systems are usually in twoNetwork operating systems are usually in two parts parts server server and and client/requesterclient/requester. The . The requester makes disks, software, ports and requester makes disks, software, ports and other facilities available to the workstation other facilities available to the workstation for the server on request, such as print for the server on request, such as print services and data sharing. Each service services and data sharing. Each service requested by a station is accessed via the requested by a station is accessed via the client software.client software.

The misuse of networks and The misuse of networks and applicable Actsapplicable Acts

The laws which apply to the misuse of networks The laws which apply to the misuse of networks include the include the Copyright, Designs and Patents Act Copyright, Designs and Patents Act 19881988, the , the computer Misuse Act 1990computer Misuse Act 1990, and the , and the Data Protection Act 1998Data Protection Act 1998..

Since these Acts were passed, individuals may be Since these Acts were passed, individuals may be

prosecuted for carrying out certain activities prosecuted for carrying out certain activities relating to networks which are classified as illegal. relating to networks which are classified as illegal. Any convictions which is made is a result of the Any convictions which is made is a result of the application of these Acts.application of these Acts.

Review the Intermediate 2 course for these three Review the Intermediate 2 course for these three Acts.Acts.

Documents

Networks Unit 1 - Computer Systems St Kentigern’s Academy