Introduction to Networking and Data Communication

Network Topologies

By the end of the lesson you should be able to: Describe bus, ring, and star topologies state the advantages and disadvantages of each topology

Topology - refers to how the nodes of a network are connected.

Types of Topology

• star topology
• ring topology
• bus topology

Star Topology

This is where all cables for each computer is being connected directly to the server via a hub or a switch. This implies that for hosts to communicate they have to do so through the server

Advantages

• each computer has a direct line to the server hence communication is very fast
• when there is a fault on the wire linking the host and the server, there is no interference with the rest of the network i.e it is reliable.
• a node can be added or removed without interfering with the entire network i.e it scalable
• network management can be done centrally

Disadvantages

• failure of the central switch node may bring down the entire network
• more cabling is required hence expensive

Bus Topology

This is where is a single central trunk/cable/backbone/bus on which all the workstations are connected. Usually, the trunk/bus/backbone has a terminator on both ends to prevent signal loss.

Advantages

• new computers can be added without disrupting other computers
• installing a bus topology network is easy
• it is less costly

Disadvantages

• any fault/breakage along the backbone brings down the whole network
• determining the point of failure is very difficult
• since there is a high rate of collision during data transmission, very few computers can be connected to the network at a time
• every workstation can see all the data on the network

Ring Topology

it is where the workstations are set out in a ring using a cable. A token is usually passed along the ring from node to node and if the token is meant for a given node then it releases the information to the network

Advantages

• uses a shorter cable hence economical
• it easy to install
• it provides high speed unidirectional communication

Disadvantages

• if any computer breaks down, communication is hampered in the ring

Network Topologies Link