Computer Networking

Abdul Rehman

Outline• Classification of Networks• Major Types of Networks• Topologies of Network for Local Area Networks

Networking• A network can be defined as two or more computers

connected together in such a way that they can share resources.

Networking Definition Cont..A resource may be:• A file• A folder• A printer• A disk drive etc.

Classification of Network

• A local area network (LAN) is a computer network covering a small geographic area, like a

• home

• office

• group of buildings

The Local Area Network (LAN)

Client

Client Client

Client Client

Client

Wide Area Network (WAN)

• Wide Area Network (WAN) is a computer network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries).

• The largest and most well-known example of a WAN is the Internet.

Wide Area Network

Fundamental Network Classifications Cont..

Metropolitan Area Network (MAN):o A metropolitan area network (MAN) is a network that

interconnects users with computer resources in a geographic area or region larger than that covered by even a large local area network (LAN).

Metropolitan Area Network (MAN)

Client and Server computer role in networking

• Server computer is a core component of the network, providing a link to the resources necessary to perform any task.

• Client computers normally request and receive information over the network client. Client computers also depends primarily on the central server for processing activities

Peer-to peer network (P2P)• A peer-to-peer network is a network where the computers

act as both client and servers.

Peer-to peer networking (P2P)

Client/Server Networking• In this design, a computer or small number of computers

are designated as centralized servers and given the task of providing services to a larger number of user machines called clients

Client/Server Networking

Network Topologies• A topology is a way of “laying out” the network.

Topologies can be either physical or logical. • The Major type of network topologies include Star, Ring,

Bus and Mesh topologies

Star Topology• Star topology is the most general type of network

arrangement that is used in offices and homes• The communication takes place via hub, which acts as a

common connection device.• All the data initiated by nodes passes through the hub. • Hub also manages and controls the whole network

Star Topology

Star Topology Cont…• Advantages of Star Topology:

• The star topology is easy to install• If any node fails it does not affect the network

• Disadvantages of Star topology• If the hub goes down, the whole network will be blocked

Ring Toplogy• In a ring network, the nodes are attached with each other

in a circle.• Each node has exactly two neighbors.• The computers and devices connect each other and

complete network

Ring Topology

Ring Toplogy Cont…• Advantages of Ring Topology

• There is no central node for controlling the network

• Disadvantages of Ring topology• The transmission signals go in sequential order which create

delays• A single break in cable can disturb the flow of whole network

Bus Toplogy• Bus toplogy is one of the most simple network topology • In bus topology all the nodes are connected into a single

cable.• This central cable is the backbone of the network

therefore it is known as the Bus• Every node send and receive through this Bus.

Bus Toplogy

Bus Toplogy Cont…• Advantages of the bus toplogy

• It is easy to add new node in bus toplogy• Bus topology requires smaller cable length as compared to star

topology

• Disadvantages of bus topology• If main cable breaks the whole communication system goes down.• If the number of devices is increased it drops down the efficiency

of bus network.

Mesh Topology• A mesh topology is made up network

where each node is interconnected with each other.

• It provides a one to one connection between devices on the network.

• The arrangement of mesh technology is very expensive

THE END