Brouter Ports; Spanning Tree And Vlans - Avaya 8800 Configuration Manual

can use any virtual router interface address to access the switch if routing is enabled on the
VLAN.

Brouter ports

The Ethernet Routing Switch 8800/8600 supports brouter ports. A brouter port is a single-port
VLAN that can route IP packets and bridge all nonroutable traffic. The difference between a
brouter port and a standard IP protocol-based VLAN configured to perform routing is that the
routing interface of the brouter port is not subject to the spanning tree state of the port. A brouter
port can be in the blocking state for nonroutable traffic and can still route IP traffic. This feature
removes interruptions caused by Spanning Tree Protocol recalculations in routed traffic.
Because a brouter port is a single-port VLAN, each brouter port decreases the number of
available VLANs by one and uses one VLAN ID.

Spanning Tree and VLANs

The main difference between a brouter port and a standard IP protocol-based VLAN (that is
configured for routing) is that the port spanning tree state has no effect on the brouter port
routing interface. Therefore, when you use a brouter port, the spanning tree protocol is
eliminated from the backbone network.
If you require VLAN connectivity in the core to support non-IP protocols, make sure that the
spanning tree does not cause blocked ports. Blocked ports can occur if you use a single
spanning tree group (STG) instance with multiple VLANs (see the following figure).
Configuration — OSPF and RIP
VLANs and routing
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