Overview of VPWS Implementation
The Virtual Private Wire Service (VPWS). VPWS is a point-to-point service. There is one PW connecting two end points.
The LER processes the received Ethernet frames before encapsulating them with PW and LSP Headers.
The untagged Ethernet frames can be forwarded to the “MPLS-TP Encapsulation”
− without changes,
or
− with added PW tag.
The tagged Ethernet frames can be forwarded
− without changes,
− with changed tag (the ETH VLAN ID is changed to PW VLAN ID),
or
− with added PW tag.
The ENP Service creation defines how the Ethernet frames are handled based on the configured Service type.
Port Based means the AC frame can be untagged, priority or VLAN (PW) tagged.
− AC Port Based, No Change (figures 1 and 3),
− AC Port Based, Add PW Tag (figures 2 and 4).
With VLAN Based, the AC frame must be VLAN tagged.
− AC VLAN Based, No Change (figure 3),
− AC VLAN Based, Add PW (figure 4),
− AC VLAN Based, Change Tag (figure 5).
With Untagged Based, the AC frame must be untagged.
− AC Untagged, No Change (figure 1),
− AC Untagged, Add PW Tag (figure 2).