MVRP provides a mechanism to dynamically share VLAN configuration information across layer 2 switches on a network. MVRP eliminates the need to manually configure VLANs on each switch, enabling the network to dynamically maintain VLANs based on the current network configuration. MVRP propagates local VLAN information to other devices, receives VLAN information from other devices, and dynamically updates local VLAN information. When the network topology changes, MVRP propagates and learns VLAN information again according to the new topology.

MVRP is defined in the IEEE 802.1ak standard. It perform the same functions as Generic Attribute Registration Protocol (GARP), while overcoming GARP limitations, such as bandwidth usage and convergence time in networks with a large numbers of VLANs.

MVRP makes use of the Multiple Registration Protocol (MRP). MRP provides the mechanism for switches on the same layer 2 network to transmit attribute values on a per MSTI (Multiple Spanning Tree Instance) basis. (An MSTI is a group or set of VLANs, all of which are part of the same spanning tree.)

Each MRP-enabled interface is called an MRP participant, and each MVRP-enabled interface is called an MVRP participant. When the VLAN configuration on an MVRP participant changes, it sends a Protocol Data Unit (PDU) to notify other MVRP participants to register and deregister the changed VLAN. MRP rapidly propagates the configuration information of an MRP participant throughout the layer 2 network.

MRP registers and deregisters VLAN attributes as follows:

  • When an interface receives a declaration for a VLAN, the interface registers the VLAN and joins the VLAN.
  • When an interface receives a withdrawal for a VLAN, the interface deregisters the VLAN and leaves the VLAN.

MVRP only applies to trunk interfaces.