- Topology is the way in which computer network is connected.
- Interconnection configuration to provide efficient communication.
- Arrangement of nodes, cables and connecting devices.
1) Ring topology
- Each node connected to each other forming a ring like structure.
- Data packets travels from node to node as there is single path.
- Packet travels until it finds the final destination from node to node.
- Physically it is star topology but logically its a ring topology.
- Does not require a server.
- Cable failure affects limited users.
- Acts better in heavy network load.
- Each node has access to token and opportunity to transmit.
- Failure of one node can affect the entire network.
- Adding, removing or moving nodes affects the network.
- Wiring is costly and network adapter cards are required.
2) Bus topology:
- All devices such as server, node, printer are connected to common shared cable called as a bus.
- T-connectors are used to connect each device.
- Buses are bidirectional hence all devices are capable to send and receive signals simultaneously.
- But some buses are unidirectional.
- Messages passes to each node, if it matches to its address it takes it, else it transmits to the next node.
- Bus cable is terminated at each end of node by placing terminators to prevent signal reflecting back.
- Failure of one node does not affect the network.
- Good for smaller network in LAN.
- Less expensive than star topology.
- Easy to add devices or peripherals.
- Finite over speed and size.
- Failure of main cable can shutdown the entire network.
- Terminators are required at both ends.
- Finding an error in network is difficult.
3) Star topology
- All nodes are connected to central hub.
- Hub routes the messages from source to destination.
- It acts like repeater for data flow
- Easy for installing, wiring and adding or removing nodes.
- Node failure doesn't affect the network.
- Simple to detect errors and faults.
- Good for big network.
- Hub failure can shutdown whole network.
- Expensive cabling is required.
4) Tree topology
- Central hub or root node is connected to other lower end nodes.
- Central hub manages and functions each node.
- Root node act as a server.
- Lower level nodes can be connected to next lower level.
- Point-to-point configuration wiring for each node.
- Easy to add or remove node.
- Can be use for large networks.
- Central root or node failure can shut down entire network.
- Hard for installing and configuring, compare to other topologies.
5) Mesh Topology
- Dedicated point-to-point link is established between nodes.
- It requires n(n-1)/2 links to connect n nodes.
- Any node failure doesn't affect the network.
- Traffic load is very less because of dedicated link.
- Privacy and security is maintained.
- Fault detection and isolation is easy.
- Lot of cabling and i/o ports are required.
- Installation and reconfiguring is harder.
Star topology is best suited for office and home network.