Re: XAUI and 64b/66b
Rich Taborek wrote on March 25, 15:36pm:
>
> Jamie,
>
> You are correct that the in saying that the XGMII transports ...
>
>
Rich,
I would suggest not to borrow names that were used for
years in Ethernet and then give them a completely different
content. It just confuses many people. It even confused
people to think that "the MAC was speaking HARI-style
octets through the XGMII" (Rick Walter, 3/24/00).
The MII does not speak I (IDLES). It only speaks D (raw
unencoded data), SOP (Start of Frame), EOP (End of Frame)
and ERROR. IDLES is defined as the absense of the D, SOP
and EOP (through the TX_EN control input)
The GMII does not speak I (IDLES). It only speaks D (raw
unencoded data), SOP (Start of Frame), EOP (End of Frame)
and ERROR. IDLES is defined as the absense of the D, SOP
and EOP (through the TX_EN input)
If you want to use the name "XGMII", then the XGMII should
not speak I (IDLES). It should only speak D (raw unencoded
data), SOP, EOP and ERROR. What I see instead is an
increasing variety of "IDLE" codes (K28.0, K28.1, K28.2,...)
that make this "XGMII" less and less "MII-type" and more
and more something else.
This is not what one could understand from Howard Frazier's
presentation "10Gig MII update", Nov 99, pages 6-8.
I am not, in principle, against a proposal to drop the "MII-type"
interface in the 10 Gbps Ethernet standard and use something else
that could be of better value. As with many other propposals under
consideration, I will look at it with all the respect it deserves.
I am only against borrowing names to label something that is
qualitatively different from the MII and GMII. It only confuses people
and makes the discussion much more difficult and prolonged.
Jaime
Jaime E. Kardontchik
Micro Linear
San Jose, CA 95131