AT&T is driving the white box football down the field again, announcing Friday that it has put its specifications for a distributed disaggregated chassis (DDC) white box architecture into the Open Compute Project (OCP.)
The carrier's DDC design, which was built on Broadcom's powerful Jericho2 family of merchant chips, aims to define a standard set of configurable building blocks on less costly service-class routers ranging from a single-line card systems, known as "pizza boxes," to large, disaggregated chassis clusters.
AT&T said it plans to apply the Jericho2 DDC design to the provider network edge and core routers that make up its global IP common backbone, which is the core network that carries all of AT&T's IP traffic. On an average day, the AT&T network carries more than 274.6 petabytes of data traffic, which will increase with the continued upswing of video traffic and the advent of 5G services and applications.
The company said the Jericho2 chips have also been optimized for 400G interfaces. AT&T has been preparing to go from 100G to 400G transport, which Verizon and other service providers are also prepping for, as part of its Open ROADM initiative.
In March, AT&T, Ciena, Fujitsu and Orange, along with the University of Texas at Dallas, demonstrated how optical networking equipment based on Open ROADM standards could quickly reboot in a disaster-recovery scenario.
"The release of our DDC specifications to the OCP takes our white box strategy to the next level,” said Chris Rice, senior vice president of network Infrastructure and cloud at AT&T, in a statement. “We’re entering an era where 100G simply can’t handle all of the new demands on our network. Designing a class of routers that can operate at 400G is critical to supporting the massive bandwidth demands that will come with 5G and fiber-based broadband services. We’re confident these specifications will set an industry standard for DDC white box architecture that other service providers will adopt and embrace.”
With the modular chassis design that's used in traditional high-capacity routers today, service providers buy the empty chassis and plug in vendor-specific common equipment cards that include power supplies, fans, fabric cards, and controllers.
To increase the capacity of the traditional router, the service provider can add line cards that provide the client interfaces. Those line cards mate to the fabric cards through an electrical backplane, and the fabric provides the connectivity between the ingress and egress line cards, according to AT&T.
With the DDC design, line cards and fabric cards are used as stand-alone white boxes with their own power supplies, fans and controllers. In addition, the backplane connectivity can be replaced with external cabling.
The DDC white box architecture can spin up massive horizontal scale-out because the system capacity is no longer limited by the physical dimensions of the chassis or the electrical conductance of the backplane. It also cuts down on cooling, as the components can be physically distributed if needed.
AT&T's DDC white box design includes three key elements:
• A line card system that supports 40 x 100G client ports, plus 13 400G fabric-facing ports.
• A line card system that support 10 x 400G client ports, plus 13 400G fabric-facing ports.
• A fabric system that supports 48 x 400G ports. A smaller, 24 x 400G fabric systems is also included.
AT&T said the links between the line card systems and the fabric systems operate at 400G, and use a cell-based protocol that distributes packets across various links. The design also supports redundancy in the event fabric links fail.
AT&T pioneers white box adoption
AT&T has been one of the primary drivers of white box router and switch adoption. In December, AT&T released its white box cell site router specifications into the OCP. While AT&T has been working with several vendors on its white box implementations, putting its specifications into the Open Compute Project bring even more companies into the developmental fold, which in turn benefits AT&T and OCP members.
While AT&T hasn't said which vendors it's using for the internet white boxes, AT&T is running its Vyatta software stack on them, which AT&T still plans to contribute into the Linux Foundation's DANOS community at some point this year.
The open, white box systems allow AT&T to run 10 times as much traffic as the proprietary routers it previously bought at the same price, according to a blog post by AT&T's Andre Fuetsch, president of AT&T Labs and AT&T's chief technology officer.
AT&T has internet white boxes in production on commercial traffic in Toronto and London with a goal of having them in 76 countries by the end of the year.