Networks
- Created by: miacampbell31
- Created on: 21-03-22 11:57
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- Networks
- LAN
- A network in which the computer systems are all situated relatively close to each other.
- Direct physical connection is possible due to small distance
- Network connects are normally wire cables, wireless links or fibre optic cable.
- A LAN usually serves a single organisation.
- MAN
- A network covering a highly populated area.
- Serves the inhabitants of a built-up area (often a town/city) rather than an individual organisation.
- Uses fibre optic cable and wireless to provide a powerful service.
- Close proximity of users make it cost-effective.
- WAN
- A network in which the computers are geographically remote.
- Make use of a range of connection methods, such as public telephone links, undersea cables and communication satellities.
- A WAN links the LANs in a geographically spread organisation.
- Server
- Manages network resources such as storage, files, hardware devices and communications.
- Switched hub
- Acts as a connection point for a number of network computers.
- Checks the destination/IP address of data packets and forwards them to the intended recipient
- Repeater
- Regenerates data transmission signals that have been attenuated.
- Network Card
- Connects a computer to a LAN so that it can communicate with the file server.
- Provides a port for connecting a network cable /Ethernet cable.
- Wireless Access Point
- Connects a computer to a network /router using Wi-Fi / Bluetooth.
- In a hotspot, using radio transmitters / antennae.
- Media Converter
- Changes the physical signals where different types of network link meet.
- For example, between fibre optic cable and twisted pair cable.
- Changes the physical signals where different types of network link meet.
- Connects a computer to a network /router using Wi-Fi / Bluetooth.
- IP Address
- IP Address set by the ISP.
- Linked to the physical location of the device.
- Will change / update with the location of the device.
- Linked to the physical location of the device.
- IP Address use 32 bits / 4 bytes.
- MAC Address
- Each device has a fixed MAC address.
- Which is embedded on the network card by the manufacturer.
- Each device has a fixed MAC address.
- Peer to Peer Network
- No dedicated /central server.
- All computers have equal status
- Each computer is a supplier and consumer of resourcers.
- Client Server
- Network organised around one or more servers.
- Maintains a database of passwords, access rights and authorised users.
- Acts as a file server sometimes. But main function is to provide security.
- Advantage: All resources are in one place, no problems caused by it's physical distribution.
- Advantage: Server does the required processing, only the results being sent to the client. Reducing network traffic.
- Bus Topology
- + If 1 node is not functioning, the network can still operate.
- + It is easier to add new nodes.
- + If a cable connecting a node to the backbone fails, only communication with that node is affected.
- - Collisions happen when more than one node wishes to send a message at the same time.
- Star Topology
- - cable failure means communication between the hub and the cable's single node will be affected.
- + no other communication will be effected
- + each node has own connection to hub there is no contention for pathways.
- + adding new node is easy as it just needs to be connected to the hub
- Ring Topology
- - diffuclt to add new nodes. Cable has to be severed to add.
- - broken connection in main cable will cause the network to fail. possible to isolate fault nodes.
- - data travels large distances around cable, can lead to problems with data signal.
- + Over come this, repeaters can be used to boost data signal.
- - data travels large distances around cable, can lead to problems with data signal.
- Cable Failure
- Star: Each device is connected to a central hub by it's own cable.
- If a cable fails only a single device is affected.
- More secure, data bpackets sent to/from the file server. Controls all security.
- Bus: All devices are connected to a common cable/ backbone
- If the backbone fails, all communication is affected.
- If a connecting cable fails, only that device is affected.
- Less secure, no central control of security. All nodes have access to backbone. Data packets travel in both directions.
- If the backbone fails, all communication is affected.
- Star: Each device is connected to a central hub by it's own cable.
- LAN
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