Networks
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LAN's Vs WAN's
- A local area network (LAN) supplies networking capability to a group of computers in close proximity to each other such as in an office building, a school, or a home. A LAN is useful for sharing resources like files, printers, games or other applications. A LAN in turn often connects to other LANs, and to the Internet or other WAN.
- An example of LAN is in school, its good for small areas.
WAN's
- A WAN spans a large geographic area, such as a state, province or country. WANs often connect multiple smaller networks, such as local area networks (LANs) or metro area networks (MANs)
- An example of this is Sainsburrys - when people scan things, they automatically send it to there 'base control' to order more
bus network topology
A bus network topology is a network architecture in which a set of clients are connected via a shared communications line/cables, called a bus. There are several common instances of the bus architecture, including one in the motherboard of most computers.
ring topology
A ring network is a network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node - a ring. Data travels from node to node, with each node along the way handling every packet.
star topology
Star networks are one of the most common computer network topologys. In its simplest form, a star network consists of one central switch, hub or computer, which acts as a conduit to transmit messages. This consists of a central node, to which all other nodes are connected; this central node provides a common connection point for all nodes through a hub.
Pros & Cons
Bus Networks
Pros
- It is easy to set-up and extend bus network.
Cable length required for this topology is the least compared to other networks.
Bus topology costs very less.
Linear Bus network is mostly used in small networks. Good for LAN.
- If it breaks you loose all connections on everything.
Ring Networks
- very organized.
- Each node gets to send the data when it receives an empty token. This helps to reduces chances of collision.
- all the traffic flows in only one direction at very high speed.
- Even when the load on the network increases, its performance is better than that of bus topology
- There is no need for network server to control the connectivity between workstations.
Additional components do not affect the performance of network
- Each computer has equal access to resources.
cons
- Network is highly dependent on the wire which connects different components.
Star Networks
- As compared to Bus topology it gives far much better performance, signals don’t necessarily get transmitted to all the workstations. A sent signal reaches the intended destination after passing through no more than 3-4 devices and 2-3 links. Performance of the network is dependent on the capacity of central hub.
cons
- Too much dependency on central device has its own drawbacks. If it fails whole network goes down.
Components needed to put together a network....
- sever - A computer or computer program that manages access to a centralized resource or service in a network. £342.00
- network interface card -it provided web servers which connect to the internet
- Modem - takes digital signals from a computer and then converts then to analogue, this way they can go down a telephone line.
- printer
- hub - connects lots of devices to the internet £25.00
- browser software - allows users to access webpages on the internet.