RE: [EFM] EFM Requirements
Carlos
At 02:21 PM 8/24/01 -0300, carlosal@xxxxxxxxxxxxxxxxxx wrote:
Geoff,
I agree with Howard, and I apologize if my insistence on these
questions
seems to be way out of the scope for the EFM group. I'm just trying to
keep
a broad vision of the standard, thinking about the way some companies
(such
as mine) will use it. Also bear in mind that, as non native english
speaker, it's sometimes hard for me to make my point as clear as I
wish.
You seem to be doing just fine
Concerning the frame format, my understanding
is that we'll be using the
same format already used sucessfully by Ethernet in its many
incarnations.
My remark was to remember that 802.1q is showing signs of age; the VLAN
tag
field is no longer wide enough to acommodate some of the new
applications
of the Ethernet (in fact, it was design with something completely
different
in mind). As such, I believe that the 802.1q header will end up
being
updated, and it will probably increase the maximum frame size. In the
end,
silicon must be designed to allow for bigger frames to be transmitted
at
the MAC level. It's as simple as this.
No argument regarding the market need for VLAN Tag size vs the current
standard
As for the interoperability requirement, it's
something that I just began
to realize; I'm not completely sure if it's a good idea, or even if
it's
something to be discussed at 802.3ah. My take is that all EFM
compliant
equipment should support 802.1q, either the 1998 version or a
future
update.
PHYs support packets from our MAC. This is a non-issue
The main reason is that support of VLANs on
the access network is
very important as a way to provide multiple services to every
customer,
while keeping all these services isolated into a separate logical
network.
This requirement could either be stated as part of 802.3ah, or by
another
standard group. I'm not an expert on standardization issues, though,
so
I'll leave this as an open question.
Carlos Ribeiro
CTBC Telecom
Geoff