<communications, hardware, networking> A bridge which
continuously transmits network topology information to
other bridges, using the spanning tree protocol, in order to
notify all other bridges on the network when topology changes
are required.
This means that a network is able to reconfigure itself
whenever a network link (e.g. another bridge) fails, so an
alternative path can be found. The presence of a root
bridge also prevents loops from forming in the network.
The root bridge is where the paths that frames take through
the network they are assigned. It should be located centrally
on the network to provide the shortest path to other links on
the network. Unlike other bridges, the root bridge always
forwards frames out over all of its ports.
Every network should only have one root bridge. It should
have the lowest bridge ID number.
