Spanning Tree Support - HP 10:10 LAN Bridge MB Installation And Reference Manual

Spanning Tree Support

The HP 10:10 LAN Bridge MB uses the IEEE 802.1 Spanning Tree Protocol (STP). STP
ensures that only one path at a time is active between any two nodes on the network. This
allows you to have redundant bridges on the network as backup bridges. If an active bridge or
path fails, STP automatically activates an available path through a backup bridge. For networks
with more than one possible path between any two nodes, STP must be enabled.
To enable STP, set the bridge operating state to either Learning/STP (if you want it to operate
as a learning bridge) or Secure/STP (if you want it to operate as a secure bridge). To disable
STP, set the bridge operating state to either Learning or Secure. (Bridge Off will also disable
STP, but also stops the bridging function.)
Figure 6-2 shows a network that contains three subnets connected by bridges. Bridge 1 forms
the active path between Subnet A and Subnet C. Bridges 2 and 3 form an alternative, or
backup, path for traffic between Subnets A and C.
Subnet A
Bridge 2
Bridge 1
Subnet B
Bridge 3
Subnet C
Figure 6-2. Network With Redundant Paths
6-6 How the Bridge Works