|
Carrier Services
Ethernet everywhere? 4th OIF interoperability tests begin
Three-month tests will focus on multi-domain transport and service restoration
by Doug Allen
After a year off, the Optical Internetworking Forum is back with their fourth not-quite annual interoperability testing event, AKA the “Worldwide Interoperability Demonstration 2009 — Enabling Broadband On-Demand Services” (see OIF drives on-demand Ethernet service harmony).
This latest round, begun in March, will last three months and bring together seven Tier 1 carriers across a globe-spanning test bed, focusing on a number of fairly diverse transport technologies and multi-domain service restoration. The event will encompass testing that cuts across barriers between disparate provider networks and administrative domains, technology layers, and control and management systems.
China Telecom, Deutsche Telekom, France Telecom Group, KDDI R&D Labs, NTT, Telecom Italia and Verizon form this year’s roster. This year’s goal is to define an interoperable, multi-network data and control plane technology that allows providers to instantiate dynamically provisioned broadband sessions end-to-end with the desired SLAs and QoS metrics; or put another way, establishing a standard (or implementation agreement, in this case) for cross-network Ethernet services.
To that end, the OIF is linking carrier POPs throughout the world through virtual connections to create a test network topology that can support a number of control plane schemes under OIF development. These include User Network Interface (UNI) 2.0 and its brother protocol, External Network-to-Network Interface (E-NNI) 2.0, two signaling implementation agreements crucial to inter-provider Ethernet Everywhere.
Building on the 2007 tests which trailed Ethernet Private Line over SONET/SDH control and data planes, the OIF is particularly focused on E-NNI 2.0 this time around as the lynchpin for dynamically provisioned Ethernet services, since it can deliver Ethernet services over legacy or more next-gen network protocols, and acts as the primary service activation interface, integrating all other network domain control protocols needed to carry these disparate forms of network traffic. It’s still early days for E-NNI 2.0 IA (Implementation Agreement), having been passed earlier this month, so the current interoperability testing will be both maiden voyage and the first opportunity to evaluate and tweak the emerging the (almost) standard.
If the tests go as planned, carriers can expect a formal standard for Ethernet services, especially the mesh-based Ethernet Virtual Private Line (VPLS) variant, while multiplexing transport for greater network resource control and reduced bandwidth consumption. The OIF sees EVPL as an important focus, since it believes the majority of Carrier Ethernet services, today mostly Ethernet Private Line (EPL), are moving towards more fully-switched flavors such as VPLS for its administrative simplicity and more efficient transport.
EVPL is “smarter” than EPL since it is packet-aware, but is largely deployed within a single provider’s network. The OIF will also test EVPL over several bearer layers to enable Ethernet to break out of its single-provider “island” limitations, including T-MPLS, PBB-TE and OTN.
Two of the OIF’s top priorities are making sure the control plane can simply and effectively map individual customer sessions — and their requisite QoS demands — within the overall Ethernet transport signal, so network resources can be allocated as needed, no more no less, on a just-in-time basis (or close to it, as these services aren’t quite ready for real-time implementation); and the knotty problem of service restoration across network boundaries, activated through the control plane, for fast fail-over in case of a data plane failure or outage. Using a mesh network topology, such schemes become feasible without having to allot largely unused bandwidth in a 1:1 redundancy scheme, as is commonly done with SONET/SDH.
|
|
|
