[802.3_EPOC] What is the problem with the EPoC converter, and what is the CLT?

["Salinger, Jorge" <Jorge_Salinger@xxxxxxxxxxxxxxxxx>]

Paul, David, Howard, and EPoC Study Group members,

I'm expanding a discussion that I had with Marek, Ed, and Mark to the entire team. I know this will get unruly, but I see this as a "white elephant in the room" for what seems like some sort of philosophical argument, so might as well get it out in the open. Also, I recognize that this was a subject of discussion during the meeting in Newport Beach, but I did not understand it then and thought it might not be important. I see now that it is a key problem that if not resolved will haunt us forever. So, let's see if we can discuss it via Email and see if we can resolve it before the meeting in Hawaii.

My initial statement of the problem to Ed, Mark and Marek, expanded for clarity, is: I struggle with what the CLT is, and what is the problem with the converter that we need to define. I see the EPON and EPoC systems containing these components:

EPON: OLT <=== Fiber =====================================> ONUs

EPoC: OLT <=== Fiber ====> converter <=== HFC network ====> CNUs

 

The bottom line is that I want to buy a standard OLT, and buy ONUs for customers I can connect via fiber. And, when I can't run fiber to customers, I want to buy a converter between the fiber and the HFC network so I can use the same standard OLT, and use CNUs (an RF version of the ONU) for those customers attached to the HFC network.

The FIRST KEY POINT here is that I want to use the same OLT.

The SECOND KEY POINT is that I want to buy a passthrough device that will be invisible to the OLT, which will take the optical EPON signals and convert them into RF signals. This passthrough device must be flexible in several ways, such as allowing me to use different portions of the RF spectrum, including more and less spectrum as available.

The THIRD KEY POINT is that I want the CNU to be functionally equivalent to the ONU so that the OLT does not know the difference.

I think that I want the RF PHY that the converter and the CNU will use to be defined at IEEE because that should make it easier for the vendors that will implement the converter and the CNU to develop it. 

But people tell me that this will be a problem because, from what I understand, the IEEE does not specify converters or some such rationale. Because of that we have to talk about a CLT instead of the OLT, to hide the converter inside the OLT (if I understood correctly).

I hope I was able to keep the definition of the problem simple and clean enough to have a straightforward discussion of why we can't do what I, and my esteemed MSO colleagues, need.

So, what is the problem with the converter, and why is there a need to instead define a CLT which is something I don't want to have? 

Thanks!

Jorge

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