Specifications

Chapter 4 Common Configuration
56
4.6 STP Setup ( available in AP/Gateway modes)
Spanning Tree Protocol (STP) is a link
management protocol that helps to prevent
undesirable loops occur in the network. For an
Ethernet network to function properly, only one
active path can exist between two stations. If a
loop exists in the network topology, duplication of
messages will occur and this might confuse the
forwarding algorithm and allow duplicate frames
to be forwarded.
In short, the main purpose of activating STP is to
prevent looping when you have redundant paths in
the network. Without activating STP, redundant
topology will cause broadcast storming.
To establish path redundancy, STP creates a
tree
that spans all of the switches in an extended
network, forcing redundant paths into a standby,
or blocked, state. but establishes the redundant
links as a backup if the initial link should fail. If
STP costs change, or if one network segment in
the STP becomes unreachable, the spanning tree
algorithm reconfigures the spanning tree
topology and re-establishes the link by activating
the standby path. Without spanning tree in place,
it is possible that both connections may be
simultaneously live, which could result in an
endless loop of traffic on the
LAN.