There has been interest in carrier Ethernet for a decade or more and — let's be honest –more than a little hype, too. In the early days, the focus was on how Ethernet was going to displace SONET and Synchronous Digital Hierarchy as a low-level optical technology.
Then we were going to have Ethernet to the home, or maybe to every business site. And, with the advent of Provider Backbone Transport (PBT, also called Provider Backbone Bridging and PBB-TE), we've heard people say that Ethernet was going to replace MPLS.
Today, almost all carriers rate carrier Ethernet as either no.1 or no.2 among their technology priorities, and the reason they give is PBT. With PBT, Ethernet acquires traffic-engineering features that many believe are as good as or better than MPLS; that, of course, is why there's so much fuss about the battle between PBT and MPLS today.
The real story here lies deeper, however. Network operators are looking hard at what should have been the real issue of next-generation networks (NGN) all along, which is how these networks can best form the foundation for all the services future enterprises and consumers will buy.
Ethernet isn't a replacement for SONET, nor is it the basis for enterprise-transparent LAN services or something; it's a contender for the foundation of NGNs, and that's not only big news to the industry, it's a big change in the Ethernet mission. “More and more services are based on Ethernet, as a result using Ethernet in the NGN is a logical choice,” says Aziz Ala’ali, Regional Director, Extreme Networks.
If Ethernet is going to be useful as the foundation for flexible service delivery, it needs some critical capabilities, and vendors are starting to step up and offer them. One capability that's critical is scalability and traffic engineering, which PBB and PBT provide. These let Ethernet infrastructures scale handle not only major metropolitan areas but whole countries, and simultaneously provide for stringent service-level agreements (SLA) and controlled failover modes to handle node and trunk problems.
There are many factors driving telcos to deploy carrier Ethernet, the top reason being cost and simplicity. “Carrier Ethernet is just another flavor of Ethernet, a very simple and cost effective technology. If we look at cost, the cost to acquire a bps (bit per second) is much lower than any other competing technology. At the same time, the cost to manage and maintain Ethernet is also low,” says Yarob Sakhnini, Systems Engineering Manager, Brocade.
Another trend is the change in the traditional nature of telecom products and services. Virtualisation and cloud-based application are driving significant changes in user behaviour and network resource utilization. “Service providers are left with no choice but to evolve their business model to one that more effectively manages the demand for new services, network traffic distribution, and bandwidth growth requirements, all of which can be addressed with carrier Ethernet technology,” says Mashood Ahmad, Regional Managing Director, Ciena.
He adds that though initially it was attractive due to cost, carrier Ethernet’s adoption is now primarily driven by the shift in emphasis to top-line revenue growth, which can be achieved through creation and deployment of new services with greater velocity, automation and customisation.
While its lossy nature and limited self-healing mechanisms when compared to SDH stalled Ethernet progress in the telecom infrastructure, the latest standards for QoS, traffic engineering and OAM have transformed Ethernet infrastructure into a very reliable media that can cope with the demand of the converged traffic.
“Ethernet is getting faster and faster with the introduction of production grade 40 GE and 100 GE in the very near future. Keeping this in mind, telcos will have to choose the right Ethernet platforms that can scale when they want to adopt these higher speeds of Ethernet in the near future without going through expensive and painful forklift upgrades,” says Sakhnini.
With the ever-increasing demand for bandwidth and the new crop of value-added services, carriers are being forced to rise to the challenge of providing quality service and make their networks more efficient by streamlining all their services. This can only be met with heavy use of cost-effective technologies such as carrier Ethernet which promises to make networks very simple again. If the age old adage that network simplicity is the key to network stability, carrier Ethernet sure looks the road ahead for telcos.