Basic Types of Computer Network and Topologies

Computer Network: Basic Types and Topologies

Definition of Computer Network- 

It is a set of data processing nodes which are interconnected for the purpose of data communication.

Functions of Computer Network-

• Data Sharing- It shares the data files which are stored in one computer. The data can be accessed from another computer which is present on the same or different network.
• Resource Sharing- Resources like printers, scanners can be shared by using computer network to multiple computers. This feature can reduce the cost of making the resources physical available on each computer.
• Network Security- The network can restrict the unauthorized access of the resources on computer.

Structure of Computer Network-
The network structure consists of following elements.

• Hosts- The machines, which are intended to run user programs, are known as host.
• Subnet- The hosts are connected by the subnet. It carries messages from host to host.
• Transmission Lines- It moves the bit between the machines.
• Switching Elements- These are the specialized computers which are used to connect two or more transmission Lines. The Switching elements are also known as IMPs (Interface Message Processors).

Components of Computer Network-

• Message
• Sender 
• Protocol
• Receiver
• Medium

Types of Network Architecture

Client-Server Network-

• The computers providing the service are known as the server.
• The computers which request and use the service are known as Clients.
• Cabling Cost is higher.
• It is easy to manage.
• It is used in small and large networks.

Peer to Peer Network-

• Every computer acts as both of the Server and Client.
• All the computers have equal ability.
• Cabling cost is less.
• It is generally used in small networks with few numbers of computers (less than 10).
• It is easy to manage.
• No server is needed.

Network Topologies & Its Types

It defines the way in which the computers, printers and other devices are connected. It describes the layout of the wire and devices as well as the data transmissions path.

Types of Topology-

BUS Topology- It uses a common backbone to connect all the network devices in a network in linear shape. It is a Multi point Configuration. It send and broadcast messages to all the devices attached with shared cable. Only the recipient accepts and processes the message.

Advantage of BUS Topology-

• Easy to connect, understand, install and use for the small networks.

Disadvantage of BUS Topology-

• If there is any problem in the main cable, the entire network shuts down.

STAR Topology- In it, all devices are connected to a central point known as Hub. The hub provides a centralized administration.

Advantages of Star Topology-

• It is easy to install.
• No disruptions to network if one device is removed.
• Detecting fault is easy.

Disadvantages of Star Topology-

• It requires more cable length.
• If the hub fails, all nodes must be disabled.

Ring Topology- Each device has two neighbours for communication purpose. The messages travel trough a ring in same direction.

Advantages of Ring Topology-

• Equal accessibility is there for all stations.
• The network does not fail if a link between two nodes is broken.

Mesh Topology- It involves the concept of routes. Messages can be transferred through several ways from source to destination.

Advantages of Mesh Topology-

• Data transfer is faster.
• Addition and deletion process of the nodes are easy.

Disadvantages of Mesh Topology-

• It is expensive due to lots of cabling.