The Lightwave Blog

Posted by Meghan Fuller Hanna

I've spoken with several people lately about the likelihood of the IEEE and ITU finding common ground in the development of their separate 10-Gbit PON specifications. The two standards bodies met last month in Geneva to discuss next-generation optical access and explore any potential synergies that may exist between future incarnations of EPON and GPON.

My sources tell me that the standards bodies have not made a lot of progress, and the current status is "not real rosy," as one industry insider put it. Differences at the TC/MAC layer, in particular, may be difficult to reconcile. That said, some people believe it may be possible to find some synergies at the optical layer, which strikes me as very good news.

I understand there are numerous technical hurdles to overcome in order to achieve these synergies, but imagine the economies of scale that could be derived from, say, a common laser specification for both 10-Gbit GPON and EPON. The laser is, after all, the most expensive part of the ONU.

For a lot of folks, EPON versus GPON is something of a religious debate, but if we could lower the price of 10G PON optics by doubling the volume, it may well be worth it to find some common ground. Even if the two standards continued to be developed separately but shared some key optical building blocks, it seems to me a win-win for both camps.

What do you think?

Posted by Stephen Hardy

Last week's announcement that Ciena will design in a tunable pluggable transceiver from Bookham that doesn't conform to current multisource agreements (MSAs) -- and apparently expects to have a second source deliver similar modules -- raises the question of whether there is going to be a demand for a new MSA. Such an form factor would serve as an interim step down in size between, say, an X2 and an XFP-E.

Why would the industry need such an MSA? Clearly, Ciena wanted to deliver the benefits of tunable pluggables now and couldn't find a supplier capable of meeting its requirements in an XFP-E or smaller form factor. If Ciena is willing to go with a custom size, will its competitors do the same to avoid falling behind?

Yves LeMaitre, VP of telecom sales at Bookham, says there currently aren't MSA discussions focused on his company's device. "At the same time, you are absolutely right about the need for an MSA in the coming two years," he wrote in an email when I posed the question to him. "The value of a tunable-pluggable solution is evident and we believe that the adoption rate will be extremely high amongst optical systems manufacturers."

Unless someone comes up with a tunable X2, XFP, or XFP-E soon, the pressure for a new MSA will rise. The fact that there will be at least two companies making "Ciena-sized" modules might move such an MSA into the development fast lane.

Labels: Bookham, Ciena, transceivers, tunable