E-Line service is defined in PBB (IEEE 802.1ah) as a point-to-point service over the B-component infrastructure. The Nokia implementation offers support for PBB E-Line through the mapping of multiple Epipe services to a Backbone VPLS infrastructure.
The use of Epipe scales the E-Line services as no MAC switching, learning or replication is required to deliver the point-to-point service.
All packets ingressing the customer SAP/spoke-SDP are PBB encapsulated and unicasted through the B-VPLS ‟tunnel” using the backbone destination MAC of the remote PBB PE. The Epipe service does not support the forwarding of PBB encapsulated frames received on SAPs or Spoke-SDPs through their associated B-VPLS service. PBB frames are identified based on the configured PBB Ethertype (0x88e7 by default).
All the packets ingressing the B-VPLS destined for the Epipe are PBB de-encapsulated and forwarded to the customer SAP/spoke-SDP.
A PBB E-Line service support the configuration of a SAP or non-redundant spoke-SDP.