A Forwarder is hosted by a PE device and contains the procedures to make the switching and forwarding decisions for an L2VPN.
In a VPWS L2VPN, 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 a VPLS L2VPN, a Forwarder binds a set of PseudoWires to an Attachment Circuit. A VPLS Forwarder has multiple ForwarderEndpoints.