PT-7828 User’s Manual
Featured Functions
3-36
What happens if a link failure is detected? As shown in next figure, the STP process reconfigures
the network so that traffic from LAN segment 2 flows through Bridge B.
STP will determine which path between each bridged segment is most efficient, and then assign a
specific reference point on the network. When the most efficient path has been identified, the other
paths are blocked. In the above 3 figures, STP first determined that the path through Bridge C was
the most efficient, and as a result, blocked the path through Bridge B. After the failure of Bridge C,
STP re-evaluated the situation and opened the path through Bridge B.
How STP Works
When enabled, STP determines the most appropriate path for traffic through a network. The
method is described below:
STP Requirements
Before STP can configure the network, the system must satisfy the following requirements:
y
Communication must be established between all bridges. This communication is carried out
using Bridge Protocol Data Units (BPDUs), which are transmitted in packets with a known
multicast address.
