Forwarder

A Forwarder is hosted by a PE device and contains the procedures to make the switching and forwarding decisions for an L2VPN.

In VPWS, a Forwarder binds exactly one MPLS-side PseudoWire to exactly one customer-side Attachment Circuit—a VLAN or an Ethernet port, for example—that is attached to a CE. A VPWS Forwarder has exactly one ForwarderEndpoint.

In VPLS, a Forwarder binds a set of PseudoWires to an Attachment Circuit. A VPLS Forwarder has multiple ForwarderEndpoints.

For a VPWS discovered on a PE device, the MPLS Topology Server creates a Forwarder instance for the ForwarderEndpoint that it discovered and created for the VPWS on the PE device. For a VPLS discovered on a PE device, the MPLS Topology Server creates a Forwarder instance for the set of ForwarderEndpoints that it discovered and created for the VPLS on the PE device.

The MPLS Topology Server relates a Forwarder with its one or more ForwarderEndpoints and other discovered objects through the following computed relationships:

• Forwarder relationship ComposedOf

  Relates the Forwarder to its one or more ForwarderEndpoints.

• Forwarder relationship LayeredOver

  Points from a Forwarder to all LSPs that are underlying the one or more PseudoWires that are terminated by the one or more ForwarderEndpoints that are part of the Forwarder.

• Forwarder relationship Underlying

  Points from a Forwarder to the one or more PseudoWires that are terminated by the one or more ForwarderEndpoints that are part of the Forwarder.

  For a Forwarder that is associated with an Ethernet VLAN, points from the Forwarder to the VLAN.

• Forwarder relationship HostedBy

  Relates a Forwarder to the PE device that is hosting the Forwarder.