Networks

Advantages of Networking

• Users can share files
• Users can share peripherals, printers and connections to other networks
• Servers can control security, software updates and backup of data
• Communication with other people

Disadvantages of Networking

• Increased security risk to data
• Malware and viruses spread very easily between computers
• If a server fails, the computers connected to it may not work
• The computer may run more slowly if there is a lot of data on the network

LAN(Local Area Network)

• Covers a small geographical area located on a single site
• All the hardware for a LAN is owned by the organisation using it
• LANs are wired up with UTP cables, fibre optic cable or wireless using wifi

WAN(Wide Area Network)

• Covers a large geographical area, connecting LANs together
• Infrastructure between LANs is leased from telecommunication companies who own and manage it
• WANs are connected with telephone lines, fibre optic cable or satillite links

Bandwidth

• The amount of data that can be sent and recieved successfully in a given time
• This is not a measure of how fast data travels, but how much data can be sent of the transmission media
• Measured in bits per second, often called the bit rate
• Too many users of devices on the network can cause it to slow down if there is insufficient bandwidth for the data

Transmission Media

• Wired connections have a higher bandwidth than wireless connections.
• Fibre optic cables have a higher bandwidth than copper cables

The Error Rate

• Less reliable connections increase the number of errors that occur when data is transfered. This means data has to be resent until it arrives correctly
• The signal quaility of wireless connections is dependent on the range of the device from the wireless access point and other enviromental factors
• The signal quality on copper cables is determined by the grade of material used which reduces interference
• The length of the cable is also a factor

Latency

• The delay from transmitting data to recieving it.
• Latency is caused by bottlenecks in the infrastructure, for example not using switches to appropriately segment traffic on a network
• Hardware such as switches and transmission media may not operate at the same speed