As AT&T proceeds with its three-stage 400 Gigabit Ethernet (GigE) trial, the service said a key goal is to drive interoperability not only between its vendor partners, but also between fellow service providers that it has to interconnect outside of its wireline footprint.
Dan Blemings, director of Ethernet product management at AT&T, said that optical network equipment vendors and service providers run proprietary systems so each deployment has to be custom fit.
“One of the networking realities we see on the optical side is when you have a certain metro and you have gear from vendor and when you want to connect to another metro or another service provider, you have to have the same gear,” Blemings said. “Even though it’s all-optical, vendors still put their own special sauces onto their platforms.”
Whenever AT&T wants to interconnect with another service provider to satisfy a business customer’s off-net needs, the telco has assigned network field technicians who will talk to the service provider partner to determine what vendor platform they are using.
“The way we do it today at AT&T is we have network people in the field who literally pick up the phone and call another service provider we want to connect to and ask what gear they are using because we want to put a ROADM in between us,” Blemings said. “That sort of behavior needs to change in the future because we need to move faster and have our gear work together more seamlessly.”
Such interoperability will be demonstrated in the third phase of its 400 GigE trial.
AT&T will test the first instance of a 400 GbE open router platform. AT&T said the "disaggregated router" platform uses merchant silicon and open source software.
By bringing together these disparate elements, the service provider will help break free of the proprietary boundaries inherent in traditional routing and optical systems.
“There are a handful of vendors there, a lot of which are making individual components,” Blemings said. “When you think about a disaggregated router, you have various piece parts that need to be open source and are interchangeable.”
Each phase of the 400 GigE trial will prove how AT&T can not only deliver services to its customers, but also how to carry it in the network and connect with other service providers.
“Phase one and phase two will certainly prove how we can do it to a customer, it’s also proving how we can do things in our network and how we can do interconnections,” Blemings said. “Think about having your backbone ready and handing off to your customer, so it’s applicable to both scenarios.”
The key challenge for AT&T and other service providers will be in helping the industry move toward industry standards for 400 GigE.
By helping to develop industry standards, AT&T and other carriers can have a framework to deliver 400 GigE services to their customers.
“There will be challenges in that standards are still being baked in the 400G space, so as we continue to evolve and do our trials, we’re going to have to keep an eye on in the industry with standards so we’re in alignment,” Blemings said. “Whatever product we put out at the end of the day needs to be industry compliant and we’re not going to run ahead of the standards bodies.”
At the same time, many of AT&T’s vendors have not built out platforms that can handle 400 GigE yet.
“The speeds we’re looking at here are so massive a lot of the components haven’t been built yet, so we’re working with our vendors to say what needs to be built tomorrow so we can pull this trial off,” Blemings said.