* Specification for service-provider networks enters home stretch
The IEEE last week said that its 802.1Qay specification for service-provider networks has entered the final phase for ratification as a standard.
The specification details Provider Backbone Bridge Traffic Engineering (PBB-TE), a way to enable service providers to set up traffic-engineered paths across a Carrier Ethernet Network. That is, the goal is to make Ethernet more connection-oriented and deterministic at the service provider level. By doing so, the hope is that service providers will be able to serve up multimedia services at high speeds and in real-time.
When last we checked in on 802.1Qay, the group had recently released Draft 2.0. Now, the working group has reached technical agreement on the spec and has handed it over to the IEEE Standards Board for a final review.
PBB-TE turns off Ethernet’s Spanning Tree and media-access-control address-flooding and learning characteristics. The group says this enables Ethernet to evolve into a transport resource layer that can replace SONET/SDH as the data layer. The spec also allows a service provider to organize the traffic-engineered path to provide 1-to-1 resiliency.
Why would you want to replace SONET/SDH? The group argues that the same economy of scale that has gotten Ethernet this far in other network scenarios would also serve service providers well.
This effort has been attacked in the past from MPLS proponents, and in fact there are those who say that neither PBB-TE nor MPLS may win, ultimately. Tom Nolle presented an interesting argument last summer to that effect.
