Re: Proposal for accomodating 10.0000 and 9.58464 line rates

[Dan Dove <dan_dove@hp.com>]

Hi Brad,

I just returned from vacation and finally got around to reading on the HSSG
reflector. I am concerned about the packet-length-based-IFG concept for two
initial reasons.

1) It would seem to add more complexity to the MAC deferral process
by making it based on a calculation rather than a simple count. While
this might not be too difficult, the coding in the standard might be.

2) For PHYs that run at a full 10.0000, the MAC will either run at a 
lower efficiency than necessary, or there will have to be some level
of negotiation with the PHY up front... again more complexity.

I believe that adding a "Hold" signal at the XGMII is simple, allows for
a broad range of PHY implementations, and should eliminate this continued
discussion about what speed to run the MAC/PLS interface. I expected to
come back from vacation only to find total agreement on this point and
everyone looking for something interesting to talk about... so much for
my great expectations. :)

Regards,

Dan Dove