Vlan advertisement protocol (vap), Vlan advertisement protocol (vap) -8 – Alcatel Carrier Internetworking Solutions Omni Switch/Router User Manual

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VLAN Advertisement Protocol (VAP)

Page 21-8

VLAN Advertisement Protocol (VAP)

The

VLAN

Advertisement Protocol (

VAP

) is an interswitch protocol that keeps the

VLAN

membership databases stored on switches in sync and enables the auto-discovery of network
nodes.

VAP

is useful when you want all

VLAN

s to communicate over a backbone, but do not

want locally connected devices to receive all backbone traffic.

In order for a switch to participate in

VAP

exchanges,

VAP

must be enabled through a soft-

ware configuration command. The switch does not need to have attached devices that are a
part of all groups and

VLAN

s for which

VAP

information is exchanged; however, all groups

and

VLAN

s must be defined on each switch.

Each switch in a network maintains an AutoTracker database. This database is built by
observing traffic that matches user-configured policies. The

VAP

protocol reads this database

on all switches and then advertises entries in the database to all other switches in the
network.

VAP Exchanges Between Switches

VAP

updates nodes on any new entries in AutoTracker databases every 60 seconds.

VAP

also stores information in its own database. Currently this information is used by

SNMP

-

based network management software. The database contains information on

VLAN

member-

ship; it maps each learned

MAC

address to a group and to any associated

VLAN

s. This data-

base can contain information on up to

40,000 MAC

addresses.

VAP packets sent
between switches.

VAP packets sent
between switches.

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