SANTA CLARA, Calif. -- Open Networking Summit -- AT&T on Wednesday announced it will open source key networking software used in its gigabit Internet service.
The technology AT&T Inc. (NYSE: T) is open sourcing is being used by the carrier to transform expensive GPON OLTs into virtual network functions running on commodity servers and other hardware. It's part of AT&T's Gigapower gigabit Internet service for home and enterprise.
AT&T doesn't "just clone a hardware device completely in software and continue running it as before. Instead, we break out the different subsystems in each device. We then optimize each of those subsystems. We upgrade some and discard others. That's what we're doing with the GPON OLT, as well as other pieces like the Broadband Network Gateway and the Ethernet Aggregation Switch. And while we're breaking down those components, we're also releasing into open source the specifications for the commodity hardware that will run those components," says John Donovan, senior executive vice president, technology and operations, in a blog post scheduled to go live Wednesday on the AT&T Innovation Space Blog.
AT&T is virtualizing individual line cards in each OLT, combining them into a single PON media access control card. The virtual OLT "will become open hardware that reduces power consumption, scales faster, and costs less," says Donovan, who is scheduled to deliver a keynote here Wednesday.
AT&T plans to contribute the hardware specs to the Open Compute Project, so that any hardware vendor can build and sell the vOLT to AT&T and other companies, and others can "build on the concept and design," Donovan says. AT&T hopes to see prototype devices by the end of the year, with trials and deployments next year.
Also, the service provider plans to submit its customized YANG design tool into open source through the OpenDaylight community, to allow innovators to create services that plug into AT&T's software-defined framework, Donovan says.
Additionally, AT&T is working with ON.Lab building Central Office Re-architected as Datacenter (CORD), an open source system to support broadband access, like GigaPower.
Light Reading wrote about that work on Monday, while Andre Fuetsch, senior VP architecture and design for AT&T, provided us with a few more specifics on Tuesday. (See AT&T to Show Off Next-Gen Central Office.)
The stakes for AT&T's CORD efforts are big; the carrier has more than 4,500 central offices in the US. Apps running on the ONOS network operating system used in CORD will be developed by both AT&T and third-party vendors.
AT&T expects virtualizing the GPON DSLAM will improve costs by disaggregating functions to "centralize the functionality that's better suited to be centralized, as opposed to stranding it and keeping it underutilized in a particular area where it's not necessary," Fuetsch says. In particular, service profile network administration aggregation will benefit from disaggregation. "By having a disaggregated architecture it gives us more flexibility to put those functions where they are most appropriate, and to utilize them to a greater degree depending on their placement and proximity." It's a similar argument to virtualizing the RAN, he says.
Why would AT&T open source software and hardware designs it's worked hard on, rather than keeping the technology for itself? "We want to encourage greater adoption across the service provider space," Fuetsch says. "We believe the more service providers and vendors use it, the more it will drive where we need to go faster."
He adds, "This is the typical dilemma of open source. Do you want to keep it in house or take it outside? We think the advantages of taking it out outweigh any internal proprietary advantages we might have."