Ring Topology

The ring topology has a few pros but many more cons, which is why it is seldom used. On the
pro side, the ring topology is relatively easy to troubleshoot. A station will know when a cable
fault has occurred because it will stop receiving data from its upstream neighbor.
The cons are as follows:

It is expensive because multiple cables are needed for each workstation.
It is difficult to reconfigure.
It is not fault tolerant. A single cable fault can bring down the entire network.

Mesh Topology
a path exists from each station to every other station
in the network. Although not usually seen in LANs, a variation on this type of topology,
the
hybrid mesh
, is used in a limited fashion on the Internet and other WANs. Hybrid mesh
topology networks can have multiple connections between some locations, but this is done for
redundancy. Also, it is not a true mesh because there is not a connection between each and
every node; there are just a few, for backup purposes.
a mesh topology can become quite complex because wiring and
connections increase exponentially. For every
n
stations, you will have
n(n - 1)
/
2
connections. For
example, in a network of four computers, you will have
4(4 - 1)
/
2
connections, or six connections.
If your network grows to only 10 devices, you will have 45 connections to manage! Given this
impossible overhead, only small systems can be connected this way. The advantage to all the
work this topology requires is a more fail-safe or fault-tolerant
network, at least as far as cabling
is concerned. On the con side, the mesh topology is expensive and, as you have seen, quickly
becomes too complex. Today, the mesh topology is rarely used, and then only in a WAN environment
because it is fault tolerant. Computers or network devices can switch between these
multiple, redundant connections if the need arises.