Network Tropologies

(Disclaimer: this was designed for WJEC Computer Science, so this may not meet the Computing specifications)

Networks are everywhere. There are many forms of them. There are many possible networks that can be configured. However, for GCSE you will only need to know three: star, bus and ring.

Before we begin, here is some important terminology you may need to know:

• Node: “a point in a network at which lines or pathways intersect or branch”
• Server: “a computer or computer program which manages access to a centralized resource or service in a network”
• Router: “a networking device that forwards data packets between computer networks”
• Packet: “a formatted unit of data”

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RING

In a ring network, every node on the network is connected to two other node at any one time. Data can only flow in one direction at any one time in this network. This is good because this reduces the chances of a data collision, however data must be passed along each node until it gets to it’s destination. This can pose a security risk as anyone with a connection to the network can intercept the data: change it, save it or delete it entirely. Taking this into consideration there should not be an issue with this is everyone on the network is trusted because this is a closed network, and being a closed network means that computers cannot easily be added to ring so the only way there could be an attack is if an attacker got in using the server or they physically connect themselves to the network. In this network there is also the issue that if one person drops offline the whole server be affected because the connection between computers has been broken – remember that data can only flow in one direction.

This network is often used in WANs or MANs.

Here is a list of positives and negatives with this network:

Positives:

• Data flows in one direction: this eradicates the chances of a data collision
• Computers cannot be easily added: this reduces the chance of an attack on the network

Negatives:

• Data has to be passed along each node: this means that data can be intercepted
• Computers cannot be easily added: this means that if a new employee (for example) cannot join the network
• If one computer goes down, the…