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Star topology Star topology also is another example of dedicated point-to-point link which link to a central controller(hub). Unlike mesh topology ,star topology does not allow direct traffic between devices. The Hub act as an exchange:if one device wants to send data to another it sends the data to the controller/hub ,which then relays the data to the other connected device. Advantage easy to install and reconfigure. robustness.Wont effect the system if one of the link is fails. Easy fault identification and fault isolation. Disadvantage dependency of whole topology on one single point,the hub. more cable need compare to others topology like bus and ring. Star topology is usually using in Local-area network (LAN)

Mesh topology Every devices has a dedicated point to-point- link to every other device. To find the number of physical links in a fully connected mesh network with n nodes, we first consider that each node must be connected to every others nodes. Number of physical link=n(n-1) If each physical link is duplex, we can divide the number of links by 2, (n(n-1))/2. Advantage Eliminate traffic problem Robust. If one of the link is unusable, it will not effect the entire system Privacy and security Disadvantage installation and re-connection are difficult Wiring and cable required large spaces because required many cable in mesh topology Hardware can be expensive (Need lot of I/O port and cable) One practical example of mesh topology is the connection of telephone regional offices in which each regional office need to be connected to every other regional office.