at&t logoWhen AT&T begins deploying XGS-PON, perhaps in 2019, broadband speeds up to 10 Gbps won’t be the only technology advance involved. The carrier also expects to make heavy use of software-based networking and network virtualization, said Eddy Barker, AT&T assistant vice president of fixed access technology design and architecture, in an interview. Recently completed AT&T XGS-PON trials offer a preview of what we might expect to see.

Virtualization’s Role
In the trials, AT&T virtualized XGS-PON networks in Atlanta and Dallas used Open Source Access Manager Hardware Abstraction software. Among other things, virtualized equipment included optical line terminals (OLTs) and upstream broadband network gateways, Barker said.

Traditionally, in addition to offering proprietary OLTs and broadband network gateways, vendors also would have offered element management systems that only work their own equipment, Barker explained – and that system would have required a custom integration with AT&T’s operations support system, Barker said.

Today, however, “that paradigm is sort of legacy,” he observed.

AT&T’s vision now is for an open control plane that can work with any customer premises equipment that has appropriate open interfaces.

The goal of virtualization would be to “drive down the capital cost of building the network but [to also] use Open Source to allow [us] to take software and build it once and use it for a multitude of vendors’ equipment doing physical functions,” Barker explained.

With this goal in mind, AT&T has been working to “spin up a community and get everybody involved on the vendor side,” he said.

Another important goal is to have numerous software-defined access solutions, all using the same software solutions. The virtualization work that AT&T is doing for XGS-PON will also apply to other access technologies such as Gfast, the company noted in a press release.

Initially AT&T will have a relatively small number of clouds in each city to support network virtualization, but eventually the company will “start pushing down more virtualized network functions” and will move toward distributed data centers closer to the network edge, Barker said.

“It’s all about [how to] operate more quickly, with lower latency [for a] better customer experience,” he added.

AT&T XGS-PON Plans
AT&T currently uses GPON to support speeds up to 1 Gbps, primarily to residential users. The company is looking at XGS-PON technology as its next evolutionary step to serve business customers and to provide small cell backhaul in addition to serving residential broadband.

“Going forward, it gives us the ability to get multiple gigabits,” explained Barker.

This year will be a big one for AT&T XGS-PON development efforts and the carrier “will look diligently at build plans beyond 2018,” he said. “In 2019, we will have the ability to deploy XGS-PON cost effectively.”

XGS-PON deployment goals include “taking advantage of as much of [an] Open Source strategy as we can,” Barker said.