Ethernet started out as a best effort protocol for the LAN. It has since evolved to become the dominant connection protocol for carriers too.
The Metro Ethernet standards have been evolving since at least 2006. The latest major evolution in Metro Ethernet is now finding its way into the marketplace with the Carrier Ethernet 2.0 (CE 2.0) certification.
Twenty of the top networking vendors in the world, among them Cisco, Juniper, Ciena and Huawei, have now passed the CE 2.0 certification process and are set to usher in a new era of Carrier Grade Ethernet services.
John Hawkins, senior adviser for Carrier Ethernet at Ciena, explained to Enterprise Networking Planet that CE 2.0 introduces a host of techniques and mechanisms for handling things like multi-level quality of service and handoffs between operators.
"We have been talking about Quality of Service for years and what's different here is that the mechanisms are all standards-based and the handoffs between operators is now significantly easier," Hawkins said. "Having a standard eliminates a lot of inter-operator negotiations and lawyers that you used to have to figure out, and now you can just refer to a Metro Ethernet Forum (MEF) compliant service."
The path to the CE 2.0 has been a very long one. Hawkins explained that in the past, the Metro Ethernet Forum (MEF) had been issuing standards on an intermittent basis with number such at MEF14 for specific items.
"In 2006, people used to talk about being MEF14 certified and it wasn't called CE 2.0 back than because we didn't coin the term CE until we hit 2.0," Hawkins said. "Now there are so many different documents that can be certified, it has all been put under the CE 2.0 umbrella."
Carrier Ethernet Interoperability
Interoperability for Ethernet is relatively straight forward. Hawkins noted that if you plug an Ethernet plug into an Ethernet port, it's going to work.
"The question is about how to maintain some semblance of an SLA (Service Level Agreement) across inter-operator links to insure consistent levels for quality of service," Hawkins said. "What the MEF standards do is define a common denominator that enables operators to map against."
Carrier Ethernet in many cases is being uses as a replacement for SONET-SDH, which at one time completely dominated the carrier landscape.
The CE 2.0 standard in many ways is trying to replicate some of the capabilities that had already been present and widely deployed in the legacy SONET network.
"We're trying to match what we already have in SONET," Hawkins said.
Hawkins noted however that in the early days of SONET, inter-carrier issues were also a topic that took years to work through.
"SONET had the same kind of tooth cutting exercises early in its day but eventually AT&Ts T-1 could be carried across Verizon's T-1 and it just worked," Hawkins said. "What CE 2.0 does is get us to that same equivalent point, but with an Ethernet handoff."