News

AT&T Submits White-Box Router Spec for Open Computing

• By David Ramel
• 10/07/2019

AT&T submitted specifications for a new white-box architecture to the Open Compute Project (OCP), targeting service provider-class routers with chips optimized for 400 gigabits per second (400G) speeds to meet evolving network demands.

Those demands result from new technologies such as 5G and fiber-based broadband services.

To meet these growing demands, AT&T's spec incorporates a Distributed Disaggregated Chassis (DDC) design, prominently featuring 400G Jericho2 merchant silicon chips from Broadcom.

Meeting growing demands is part of the mission statement of the OCP, which describes itself as "a collaborative community focused on redesigning hardware technology to efficiently support the growing demands on compute infrastructure."

To support that mission, the AT&T spec provides a new take on the traditional modular chassis design for high-capacity routers, incorporating stand-alone white boxes that bundle formerly separate equipment cards that provided components for power supplies, fans and controllers.

The three key building blocks for the new white box design were listed as:

• 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.

Four typical DDC configurations were presented as:

• A single line card system that supports 4 terabytes per second (Tbps) of capacity.
• A small cluster that consists of 1 plus 1 (added reliability) fabric systems and up to 4 line card systems. This configuration would support 16 Tbps of capacity.
• A medium cluster that consists of 7 fabric systems and up to 24 line card systems. This configuration supports 96 Tbps of capacity.
• A large cluster that consists of 13 fabric systems and up to 48 line card systems. This configuration supports 192 Tbps of capacity.

"The release of our DDC specifications to the OCP takes our white box strategy to the next level," said AT&T exec Chris Rice. "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."