MVRP Overview

In a large bridged local area network with many interconnected switches, manual management of VLANs is complicated and prone to human error. Multiple VLAN Registration Protocol (MVRP) is a Multiple Registration Protocol (MRP) application that helps to create VLANs dynamically (VLAN registration) and automate the administration of VLAN membership (distribution and deregistration) within the network without manual intervention.

MVRP provides IEEE 802.1ak-compliant VLAN pruning and dynamic VLAN creation on switch ports connecting access and core switches. An MVRP-aware switch can exchange VLAN configuration information with other MVRP-aware switches, prune unnecessary broadcast and unknown unicast traffic, and dynamically create and manage VLANs on switches. MVRP allows the propagation of VLAN information from device to device. With MVRP, an access switch can be manually configured with all the desired VLANs for the network, and all other MVRP-enabled switches on the network learn those VLANs dynamically. The network administrator does not have to manually configure the VLANs in each of the devices in the topology. When the VLAN configurations on a switch are changed, MVRP automatically changes the VLAN configurations in the required switches.

MVRP maintains the following advantages:
  • Reduces the broadcast, unknown-unicast, and multicast traffic (BUM traffic) scope to the interested devices or switches in the network. If there are no active users for a VLAN at a remote destination, then traffic is dropped at source itself thereby efficiently utilizing the network bandwidth.
  • Reduces the chances of errors in VLAN configuration by automatically providing VLAN ID consistency across the network. In addition to this, if the VLAN configuration on a switch changes, MVRP automatically changes the VLAN configurations in the affected devices.
MVRP allows bridges in a bridged LAN to issue and revoke declarations of a VLAN attribute.
  • When a port receives a VLAN attribute declaration message, it joins the VLAN and propagates that VLAN declaration on other MVRP ports.
  • When a port receives a VLAN attribute withdrawal message, it leaves the VLAN and propagates that VLAN withdrawal on other MVRP ports.

Beginning with FastIron 08.0.90, GARP VLAN Registration Protocol (GVRP) is not supported on ICX platforms. MVRP is a successor to GVRP, and Ruckus recommends using MVRP which is more efficient than GVRP due to the protocol design. MVRP is not backward-compatible with GVRP and therefore will not interoperate with GVRP.

MRP messages used by MVRP

MVRP uses MRP messages to issue or withdraw declaration of VLANs to other MVRP-aware switches. The following MRP messages are used by MVRP:
  • Empty: MVRP information (VLANs) is not declared and not registered.
  • In: MVRP information is not declared but the VLAN is registered.
  • JoinEmpty: MVRP information is declared but the VLAN is not registered.
  • JoinIn: MVRP information is declared and the VLAN is registered.
  • Leave: MVRP information that was previously declared is now withdrawn.
  • LeaveAll: All the registered VLANs are unregistered and the VLANs need to be reregistered.
  • New: The MVRP information is new and the VLAN may not be registered yet.

The JoinIn, JoinEmpty, and New messages are declarations, while Leave and LeaveAll messages are withdrawals.

MVRP Timers

MVRP uses MRP messages to make or withdraw declaration of VLANs to other MVRP-aware switches. MVRP timers define the interval at which MVRP updates (VLAN join or VLAN leave messages) are transmitted. MVRP global timers are enabled by default. Global timer configurations reflect on all MVRP-enabled ports in the system. MVRP timers are per interface level and apply only to the specified interface. MVRP timers must be set to the same values on all the devices that are participating in MVRP. Interface-level timer configuration takes precedence over global timer configurations.

MVRP has the following timers that determine the interval for VLAN declaration and withdrawal events:
  • Join timer: Defines the interval for the MVRP PDU transmit that makes VLAN declaration on other MVRP-enabled interfaces.
  • Leave timer: Defines the time period an MVRP-enabled interface waits after receiving a leave message on the port to remove the port from the VLAN indicated in the leave message. If the interface receives a VLAN join message before the timer expires, the VLAN remains registered.
  • Leave-all timer: Defines the time interval at which a port (MVRP participant) generates LeaveAll PDUs.

MVRP Registration Modes

There are two registration modes that define the VLAN participation in MVRP:
  • Normal: In this mode, the interface accepts all MVRP messages and participates in MVRP. This is the default registration mode setting.
  • Forbidden: The registration mode of MVRP can be set to forbid the VLAN from participating in MVRP. If the VLAN is added to the forbidden VLAN list using the mvrp registration-mode forbidden command, MVRP neither declares nor registers any VLANs on the port. All the registration messages received for those VLANs are ignored. By default, the registration mode is set to Normal, which allows the VLAN to be learned or declared through MVRP.
Note: Whenever an access port is added to a VLAN or whenever MVRP ports are statically tagged to the VLAN, the registration mode of all the MVRP ports is automatically set to Fixed for that VLAN.

You can also set the applicant state of the port that defines MVRP participation of the port. If a port is configured as non-participant, MVRP PDU transmission will be prohibited on the port. By default, the applicant mode of the port is a normal participant, which allows VLAN registration and propagation of VLAN information.