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RE: Proposal for accomodating 10.0000 and 9.58464 line rates

Hi Shimon,

I knew there had been a non-frame-based proposal for 802.3x so I should have
realized that there was probably previous work done that could be
referenced.  There was also a proposal along these lines in the early days
of 802.3z to support flow control for full duplex repeaters.  In both cases
it was conceptually different from today's issue because these proposals
were for the PHY to generate a flow control signal based on some information
obtained from the far end of the link, whereas today we are asking the PHY
to generate the signal based on local conditions.  The impact on the MAC is
the same, however, regardless of how the PHY generates the signal.

Regarding having to implement half-duplex functions in a 10G MAC, I guess
this proposal does require some of this.  I would have thought that the bulk
of the half-duplex complexity was in collision handling, backoff, and
retransmission.  How painful is deference by itself?


> ----------
> From: 	Shimon Muller[SMTP:Shimon.Muller@xxxxxxxxxxx]
> Reply To: 	Shimon Muller
> Sent: 	Friday, July 23, 1999 2:23 PM
> To: 	stds-802-3-hssg@xxxxxxxx
> Subject: 	Re: Proposal for accomodating 10.0000 and 9.58464 line rates
> Steve,
> This proposal is very similar to the proposal that some of us presented to
> 802.3x a few years ago. At that time the Task Force decided to go with a
> frame based approach, but the the basic mechanism that we had would work
> here.
> I still have the changes that were needed to accommodate the interfaces
> and
> the PASCAL code, so we can leverage from that.
> The main problem that I have with it though, is that the 10-GE MAC will
> still
> have to implement quite a bit of the half-duplex functionality. I kinda
> hoped
> that we can get rid of it once and for all....
> 							Shimon.