A bus network topology is a network architecture in which a set
of clients are connected in a linear fashion via a shared communications line (backbone),
called a bus.
With a bus topology, when a computer sends out a signal, the signal travels the
cable length in both directions from the sending computer. When the signal reaches the
end of the cable length, it bounces back and returns in the direction it came from(signal
bounce). Signal bounce is a problem, because if another signal is sent on the cable length
as the same time, the two signals will collide and be destroyed and then must be
retransmitted. For this reason, at each end of the cable there is a terminator. The
terminator is designed to absorb the signal when the signal reaches the end, preventing
signal bounce. Advantages
Ã˜ Easy to implement and extend.
Ã˜ Requires less cable length when compared to star topology.
Ã˜ Well suited for temporary or small networks not requiring high speeds
Ã˜ Cost effective that other topologies.Disadvantages
Ã˜ Difficult to administer/troubleshoot.
Ã˜ Scalability is very low.
Ã˜ Problem with the backbone cable leads to entire network failure.
Ã˜ Performance degrades as additional computers are added or on heavy
traffic.( If many computers are attached, the amount of data flowing
causes the network to slow down.)
In star topology, all computers are connected through one central device
known as a hub or a switch. All the pheripheral nodes (computers) can thus communicate
with all others by transmitting to and receiving from, the central node (hub/switch) only. Advantages
Ã˜ Scalable, easy to set up and to expand.
Ã˜ Failure of a single cable or a single computer doesnot affect the entire
Ã˜ Easy to a administer/troubleshoot.
Ã˜ Data packets are sent quickly as they do not have to travel through any
Ã˜ Extra hardware (Hub/Switch) required.
Ã˜ Failure of Hub/Switch leads to entire network failure.
A ring network is a network topology in which each node
connects to exactly two other nodes, forming a circular pathway for signals: a ring. Data
travels in one direction from node to node, with each node handling every message. Advantages
Ã˜ Signal degeration is low because each workstation is responsible for
regenerating or boosting the signal.Disadvantages
Ã˜ The biggest problem with ring topology is that if one computer fails or the
cable link is broken the entire network could go down.
Ã˜ When there is a cable change or when a workstation is moved in the
network, brief disconnection can interrupt or bring down the entire
A mesh topology consists of a network where every device on
the network is physically connected to every other device on the network. Advantages
Ã˜ Fault Tolerance
Ã˜ Provides great deal of performance and reliability.Disadvantages
Ã˜ Very hard to administer and manage because of numerous connections.
Ã˜ Costly because of the additional cabling and network interfaces to create
multiple pathways between each system.
A hybrid topology is a combination of any two or more
network topologies.For Example, a popular hybrid topology is the starbus
topology, in which a number of star topologies are connected by a central bus topology.3