Virtual Routing Between Vlans; Brouter Ports - Avaya ERS 8800 series Configuration Manual

IPv6 routing fundamentals

Virtual routing between VLANs

The Avaya Ethernet Routing Switch 8800/8600 supports wire-speed IP routing between
VLANs. As shown in
VLAN 2 reside on the same switch, for traffic to flow from VLAN 1 to VLAN 2, you must route
the traffic.
When you configure routing on a VLAN, an IP address assigned to the VLAN is the virtual
router interface address for the VLAN. The VLAN IP address is called a virtual router interface
because it is associated with no particular port. The VLAN IP address can be reached through
any VLAN port, and frames route from the VLAN through the gateway IP address. You can
forward routed traffic to another VLAN within the switch.
Figure 7: IP routing between VLANs
When you enable Spanning Tree Protocol on a VLAN, the spanning tree convergence must
be stable before the routing protocol becomes active. This requirement can lead to an
additional delay in IP traffic forwarding.
Because a port can belong to multiple VLANs, a one-to-one correspondence no longer exists
between the physical port and the router interface.
As with any IP address, you can use virtual router interface addresses for device management.
For the Simple Network Management Protocol (SNMP) or Telnet management, you can use
any virtual router interface address to access the switch while routing is enabled on the VLAN.

Brouter ports

The Avaya Ethernet Routing Switch 8800/8600 also 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 protocol-based VLAN configured for routing is that the
routing interface of the brouter port is not subject to the spanning tree state of the port. A brouter
32 Configuration — IPv6 Routing
Figure 7: IP routing between VLANs on page 32, although VLAN 1 and
November 2010