Local Area Network telecommunication 201 Group member: Deema Alharbi 200600617 Noura Almusailem 200700066

Introduction: Local Area network otherwise commonly known to everyone as LAN is quite simply the system that facilitates communication between computers and devices. In other words, when two or more computers are connected to each other in close proximity it is local area networks. In order for these computers to communicate they have to have the same set of protocols and hardware that are pre defined. Out of the other area networks, LAN is the most commonly used and is popular since it is the most practical and low cost option. LAN networks are most commonly used in offices, industries, schools, universities, factories among many other places. The function of LAN is to link many computers in tandem and connect them to output devices such as printers. For example, in a computer lab that has fifteen computers and only one printer, the best way to connect the network is by using a LAN, this way instead of connecting each of the computers to the printer, a network can be created and data can be transmitted much easily and can help avoid the clutter of too many wires.

In the late 1960's there was an increased demand for connecting computers together especially in university research labs. Cambridge University in 1974 developed the Cambridge ring, although this never went on to become a commercial success. Xerox PARC went on to develop the Ethernet in 1975. In 1976 Datapoint Communications went on to develop the ARCNET, which was commercially installed at Chase Manhattan Bank. Here onwards LAN developed into what it is today. There was a need for standardization since each company or developer was making their own system. With the help of the Institute of Electrical and electronics Engineers (IEEE) there was standardization.

Methodology: Considering that this research is based on theory that has already been investigated, there is no need for commonly used research tools such as surveys, questionnaires, interviews. Instead all of the research will be done from traditional sources such as books, research papers, internet websites and textbooks.

Analysis: Understanding packet switching is important since it forms the basis of the Area networks. These area networks are mainly defined by the distance they span. The following table differentiates the different types

Wide Area Network covers large area eg. The internet LAN WAN Definition Local area network, covers a small area, such as office, home, schools ec. Wide Area Network covers large area eg. The internet Speed High (1000mbps) Lower (150mbps) Data transfer rate High Low Cost Least expensive Medium to very expensive Components Layer 2 devices such as switches, layer 1 devices like hubs and repeaters Layer 3 devices such as routers and multiplayer switches Error rate Higher Bandwidth

A point to point network is one where two computers are connected to each other and can share information. By using LAN the computers on a network can communicate in such a way that any computer on the network can communicate with any other computer on the same network. Hence coining the term Multi Access networks. In terms of technologies for LAN many have been invented. The key difference is in their shape otherwise known as LAN topology. The following are some of the LAN topologies.

Bus Topology: Bus topology networks are formed when a single cable is attached to computers. A computer attached to a bus has the capability to send a signal down the cable and all the other computers in the network will receive the signal.

Ring Topology: In this type of network topology the computers are connected to a closed loop.

Mesh Topology: This type of topology establishes connections between each two pairs of computers. This type of topology requires many cables and many connections hence isn’t widely used.

Devices used in LAN: Hub: An Ethernet hub is a device that connects multiple Ethernet devices together hence making them behave like a single network segment. It has multiple input/output (I/O) ports. Router: A router is a device or, in some cases, software in a computer, that finds the next network point to which a packet should be sent. The router is usually connected to at least two networks and it decides which way to send each information. It is based on its current understanding of the state of the networks it is connected to.

Conclusion: A LAN is a very useful and widely used technology in offices, work places, industries, due to its unique nature and is very useful. The devices used in a LAN are many and each serves a vital function in ensuring the connectivity. There are many topologies of the way a LAN can be set with the most efficient being the star topology. It is the cheapest of the packet switched networks and compared to the others is the best option.

The following table summarizes the advantages and disadvantages of LAN: Can share costly hardware ex. Plotter printers Cheaper to buy network software than individual software All users can have access to all files Messages can be exchanged between users Internet connection can be shared Very expensive to set up and maintain Prone to virus, since it can spread to all computers in the network Prone to hacking If server goes down, the whole network may shut down

Thank you for listening. Feel free to ask.