Router interface types
Two types of router interfaces are supported by a Passport 8600 module:
- A Passport 8600 module supports the concept of brouter ports. A brouter
port is a single-port VLAN that can route IP packets as well as bridge all nonroutable traffic. The difference between a brouter port and a standard IP protocol-based VLAN configured to do routing is that the routing interface of the brouter port is not subject to the spanning tree state of the port.
A brouter port is actually a one-port VLAN; therefore, each brouter port decreases the number of available VLANs by one and uses one VLAN ID.
- Virtual router interfaces correspond to routing on a virtual port that is associated with a VLAN. This type of routing is the routing of IP traffic to and from a VLAN. Because a given port can belong to multiple VLANs (some of which are configured for routing on the switch and some of which are not), there is no longer a one-to-one correspondence between the physical port and the router interface. For VLAN routing, the router interface for the VLAN is called a virtual router interface because the IP address is assigned to an interface on the routing entity in the switch. This initial interface has a one-to-one correspondence with a VLAN on any given switch.