Types of Network Topologies (Bus, Ring and Star)

NETWORK TOPOLOGIES:

• The term topology refers to the way a network is laid out.OR

• Cabling layout of a Network is called Network Topology.OR

• Physical layout of a network is called Network Topology.

• Network topologies are
• o Bus Topology or Linear Topology
• o Star Topology
• o Ring or Token Topology
• o Mesh Topology
• o  Tree Topology

Bus Topology:

• All Computers will be attached with a long cable called a Bus or Trunk or Back bone cable.
• Multi-Point Communication.
• No security of data.
• Not recommended for large or sensitive networks.
• T-Connectors and Terminators are used.
• It uses Carrier Sense Multiple Access (CSMA) technology for data transmission.

Advantages are

1. o       Least amount of Cabling of any topology.
2. o       Suitable for small network
3. o       Adding additional nodes is easy

Disadvantages are

1. o       If main Cable breaks, then whole Network will goes down.
2. o       If any link goes down, then network will goes down.
3. o       Only one medium for Data Transmission so Transmission Speed is very slow.
4. o       Terminators are requires at the both ends.

Star Topology:

• Most common use now a day.

• Point-to-Point or Uni-cost Communication.

• Security of data.

• All Computers will be connected to a Central controller, usually called a HUB or Switch.

• Central device (Switch or HUB) has addresses of all computers connected to it.

• If one device wants to send the data to another, it sends the data to the controller, which then relays the data to other connected devices.

Advantages are

1. o       Fast Communication Speed as compared to Bus Topology.
2. o       Easy to install and wire.
3. o       If one computer fails, no effect on network.
4. o       Easy to detect and remove faults.

Disadvantages are

1. o       High installation cost as compared to Bus Topology.
2. o  If central device fails then entire network will goes down.

Ring Topology:

• Its shape is just like a ring.

• Also called Token Ring Topology.

• Connects the nodes (computers) in a circular Chain.

• Point-to-point Communication only with two devices on either side of it.

• A signal or Token is passed along the ring in the direction (Anti Clock Wise), from device to device, until it reaches its required destination.
• Better Performance than Bus Topology but less effective than Star Topology.

• Not very common used for large networks.

Advantages are

1. Adding additional nodes is easy.
2. All computers have equal access on network.

Disadvantages are

1. Difficult to configure
2. If Cable breaks, then whole Network will goes down.
3. If any link goes down, then network will also goes down.
4. Only one medium for Data Transmission so Transmission Speed is very slow.