On 1/6/20 11:05 AM, Mike Hammett wrote:
What is the vendor-lock scene like in the world of OLT optics? Is it as bad as Ethernet optics? If it exists, is there actually a good reason for it (other than money)?
My experience has been that it's arguably worse. Some sort of vendor lock is downright common often with no way to override it. Of course, you can always re-code the optics, but bleh. The claims usually are that GPON (and PON in general) is more sensitive to timing and DDM characteristics of the optic than AE (which is, to a degree, true) and that OLT optics launch much higher power than typical AE optics (also true) and that therefore it's required that you use 1st party optics to maintain FDA laser compliance (which is, afaik, BS). The way I know most of this (aside from the DDM interface specifics, potentially) is BS is that the same vendor(s) generally have surprisingly little to say about the passive optics.
I'm sure I'll get people saying that for something so important, one should only deploy first-party optics, regardless of the cost. Zhone's pricing isn't bad at all.... but if there's effectively no difference, then you might as well buy the cheaper one.
My solution has been to grill my preferred OLT vendor on their 1st party optic cost. I've generally been able to get them down to the point where, while still notably more expensive than white-box offerings, it's not patently outrageous, and then I don't get support hassles which is worth at least something (even if it's largely artificial) on a port with 32+ potential users on it if I do have an apparent issue that may be related to the optics. My one complaint with fs.com optics has also been somewhat more variable launch power from unit to unit. Though they are always within spec, they seem to vary a bit more than with bigger name modules especially within a lot. That does matter a bit more with PON optics than with AE, so that is one thing to consider, too, though it's a minor complaint again since everything is always within spec. -- Brandon Martin