Carrier Ethernet Catch-All

Ethernet continues to evolve as the swiss-army knife of network protocols and services – with an increasing focus from service providers to adopt and adapt it to their own needs, and the needs of their customers.

From its roots as a relatively simple, best-effort local area network protocol, carriers, vendors and standards bodies like the Metro Ethernet Forum are continuing to add carrier-grade features, new OAM&P capabilities and extensions to the core Ethernet protocol to position the technology as a foundational element in tomorrow’s converged IP networks.

And as service providers become more adept at bending Ethernet to fit their needs, new and potentially lucrative applications for Carrier Ethernet continue to emerge. That not only includes offering Carrier Ethernet services to businesses – both as a relatively low-end T1 replacement but also as a more dynamic, high-bandwidth, gigabit-speed solution for connecting data centers and moving great loads of traffic. It also involves using Ethernet as a convergence protocol that will handle business, residential and – in an increasingly important application – mobile voice and data backhaul traffic on a consolidated IP-based network infrastructure.

“We’re seeing customers on the same network they provide Ethernet business services also looking to deliver mobile backhaul, as well as, still in its early stages, video to consumers,” said Tom Mock, senior vice president of strategic planning for Ciena. That type of network/service approach, with Ethernet as the glue, “is just beginning to come to maturity,” he said.

Beyond best effort

The key to providing those carrier class Ethernet services is the development of new capabilities to augment the core characteristics of Ethernet. Ciena’s Mock points to developments in three key areas as being most crucial:

- making Ethernet more deterministic rather than best effort to accommodate voice and video services in particular

- enabling applications that are more connection-oriented, ie, require a set-up and take-down path from a network point of view

- dealing with synchronization and timing issues, especially as Ethernet is used for applications like mobile backhaul carrying voice traffic

The industry is moving rapidly forward with work in these areas. While early approaches like transporting Ethernet over IP/MPLS using pseudowire technology or via provider backbone transport, or PBT, have gained some momentum, next-generation options are gaining adherents as well, in particular MPLS-TP (or Transport Profile). What all of these more “connection-oriented” approaches to Ethernet have in common is a goal to “set up a more explicit path in the network, just like a SONET circuit,” said Ralph Santitoro, director of carrier Ethernet market development for Fujitsu Network Communications.

Like SONET, COE features explicit forwarding of connections and bandwidth resource reservation to ensure that traffic is guaranteed to be properly delivered across the network. Combine more connection-oriented approaches to Ethernet with higher-bandwidth packet optical network technologies and the next generation of carrier infrastructure starts to come into focus, Santitoro said.

The exchange question

Further extending the reach of carrier Ethernet are emerging Ethernet exchanges. Such exchanges enable carrier customers to interconnect their carrier Ethernet offerings so that they can more easily serve end user customers wanting to interconnect multiple locations, including locations that are only served by other carriers. Mobile backhaul will also likely be an important application of carrier exchanges.

Neutral Tandem launched a carrier Ethernet exchange in February, expanding its current interconnect business – which includes customers such as XO Communications, U.S. Signal and Zayo – to include carrier Ethernet services. To support the new offering, Neutral Tandem is adding Ethernet switches and deploying a network management system to handle provisioning. “It will simplify the ordering and provisioning process and keep track of service level agreements and billing,” explained Neutral Tandem Chief Operating Officer Surendra Saboo. We have over 110 carrier customers. A lot of them would be buyers and sellers on this Ethernet exchange.”

Others are making progress on the exchange front as well. In October, collocation provider Equinix announced its service launch, followed by a similar announcement from startup company Carrier Ethernet Neutral Exchange (CENX) in November. CENX aims to streamline the process for handing off carrier Ethernet services from one network to the next, translating service characteristics from one carrier’s classifications into others’. This can take months for just one interconnection today, but CENX will establish multiple connections in just days, using common interface specifications established by the Metro Ethernet Forum.

One carrier’s vision

How can service providers parlay these trends into new revenue and business opportunities? Consider AT&T, which is rapidly expanding its carrier Ethernet capabilities, focusing in the past year on better integrating Ethernet provisioning into its own operating environment and building on the carrier-grade capabilities of the service as well as interconnection with other carriers around the world, said Sandy Brown, AT&T’s vice president of connectivity services.

Another part of AT&T’s Ethernet service focus has been adapting it to specific enterprise requirements, such as “as an access arrangement for virtual private networks or voice over IP or as access to cloud computing services,” Brown said. “On top of that, carrier Ethernet is just a very cost efficient solution for companies with high bandwidth needs. The other thing we focus on is Ethernet to the cell site, there’s just tremendous growth in data requirements for carriers and Ethernet can deliver backhaul services reliably and efficiently.

In the past year, AT&T has extended its Opt-E-MAN end-to-end switched Ethernet service to more than 38 countries, Brown said. In addition, AT&T is delivering its 10gbs private line Ethernet services to a “batch of customers,” essentially enterprises that have very high data requirements such as financial services firms of companies connecting large data centers. “Ethernet is a great fit for that application class,” Brown said, adding that such users used to do a lot of Layer 1 switching over dark fiber, “do-it-yourself-style” but now “we’re seeing more outsourcing and buying of carrier Ethernet services.”

As the market for carrier Ethernet expands, the challenge for service providers is to slash service provisioning cycle times by improving internal operational processes. “In the TDM world, the customer would send an [order] to the telco and everyone would know what to do with it. In the Ethernet world, those standards and processes are less developed,” said Brown. “There is a great opportunity for service providers to move to that next generation of capabilities.”