SAN JOSE, Calif. -- When engineers gather in October to discuss the future of Ethernet, one of the big questions will be the possibility of a 50 Gbit/s standard. The Ethernet Alliance is hosting the October 16 event in Santa Clara, Calif., billed as “The Great Rate Debate.” Engineers from Alcatel-Lucent, Avago Brocade, Broadcom, Cisco, Dell, Finisar, Intel, and Juniper are among those slated to speak.
The event comes in the wake of a surprise switchback on the Ethernet road map earlier this year. After the IEEE approved 40G and 100G Ethernet standards as the next big leaps after today’s 10G, a consortium of vendors launched an effort in June to set de facto 25G and 50G standards for datacenter servers. The IEEE quickly responded, announcing in July a new 25G standards effort.
So far the IEEE has not said anything about a 50G follow-up effort, but it would make sense for two reasons. The datacenter consortium is already planning to define a 50G rate, and 56G serial serdes and optical interconnects are in the works that would likely become the next big building blocks in communications.
“A number of people still feel the need to do 40G, and I know a number of people who want to do 50G,” says John D’Ambrosia, chairman of the Ethernet Alliance. He also chairs an IEEE effort to set a 400G Ethernet rate in which engineers are discussing 25G, 50G, and even 100G links as bases for the standard. “People are recognizing how fast the industry is moving to 50G,” he says, noting a handful of efforts underway at the Optical Internetworking Forum. “We want to align with the OIF [but] … there may be questions about how much of its 56G optical work we can pull in.”
Among other topics, engineers at the October event will take up the ongoing debate between NRZ and PAM4 modulation, and also concepts for flexible media access controllers. The new ideas suggest Ethernet is continuing to be pulled into a diversity of uses.
“It’s not one simple answer of getting everyone’s desktop on a network anymore,” D’Ambrosia says. “The economics of the application will determine the solution, and there’s no right answer -- it depends on the app.”
— Rick Merritt, Silicon Valley Bureau Chief, EE Times