The Lightwave Blog

Posted by Stephen Hardy

As part of my research for a June issue article on 100G semiconductors (When will we see them?), I spoke with John D'Ambrosia in his role as a spokesman for the Ethernet Alliance. John also happens to be the head of the IEEE P802.3ba task force charged with developing the 40- and 100-Gigabit Ethernet specifications. While talking about chips, John also had a few things to say about optics for these emerging applications. Herewith a sampling:

On keeping 40GbE and 100GbE optical specs as simple as possible: "If you look back at the 10-gig optics, what initially came out of the group was more complicated than desirable, because most of the interfaces were XAUI based and you basically wound up having several layers that you put into your optics solution -- which quickly evolved to 'take all that stuff out.' And now we have simple solutions like the XFP or SFP+."

Which doesn't mean you won't see functions pulled out second- and third-generation 100GbE modules: He foresees three stages of module evolution. which are spelled out in a whitepaper on the Ethernet Alliance site.

On the recently announced 40GbE serial effort: "For this new effort, people are looking at doing a serial-type interface at 40-gig. And the carrier people are really driving this one. They really want to see a 40-gig serial interface that will allow them to coexist easier with their OC-768 equipment....I don't know where they're going to go with the electrical interfaces on that yet, and I think that remains to be seen for that project. I think that they'll probably leverage in the short term off of the same NAUI-type interface that we're talking about [for the current singlemode-based specs], and then have your internal muxes."

On the prospects for on-time ratification of the task force's current standards work: "At this point, I don't really see anything that's going to throw us off of schedule."

Labels: 100GbE, 40GbE, ICs, standards