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Re: [EFM] EFM x 802.3ah - broad picture x narrow scope


Aside from the etymology of EFM (which Geoff addressed) I agree with what you
have said.

I think the important distinction is that:

802.3ah defines PHY characteristics (and minimal changes to the MAC).

It is up to the system vendors to develop a system that supports subscriber
access and, furthermore, the integrators to come up with a complete subscriber
access package.

Within the task force, it is worth keeping an eye on what will be required in
the real world but only from the point of view that the PHY shouldn't prevent
the correct function of the layer 1 through 7 (or 9!) solution.


carlosal@xxxxxxxxxxxxxxxxxx wrote:

> Ryan,
> I'm posting this to everyone in the group, as it sums up my opinion in the
> recent discussion about EFM scope.
> There are several seemingly incompatible requirements to meet. We have to
> maintain compatibility with other Ethernet related standards such as
> 802.1d, 802.1q, and so on; at the same time, working with public access
> networks is not the same as working with corporate customers. Some
> potential customers require long reach, others can work with short reach.
> Some of the discussions are still at a somewhat 'intuitive' stage, where we
> have few actual data to make a informed decision.
> For me, the fundamental point is that 802.3ah is not the same as "Ethernet
> First Mile". Given the name, EFM is more of a concept: it covers all that
> is needed to bring Ethernet to the access network. 802.3ah is just this
> standard group, which has to keep a narrow scope. It's fair to say that
> there are good reasons for the narrow focus. The question now is, how to
> map all the requirements of the broad picture of "Ethernet First Mile" into
> the narrow scope of 802.3ah.
> Give this scenario, the trick is to find the key points that need to
> included into the 802.3ah standard in order to support the complete EFM
> proposition, without going way out of the scope. That's a huge quest for
> the group to solve.
> Carlos Ribeiro
> CTBC Telecom