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Re: 802.3x flow control




Devendra,

With respect to 802.3x flow control, why do you say that you don't see how it can
help in the context of 10 vs 9.58460 Gbps?

My assumption is that 802.3x flow control is speed independent. For example, it
can flow control a mixed 10, 100 and 1000 Mbps Ethernet devices. Is this not true?

Devendra Tripathi wrote:

> Rich,
>
> Given that we are discussing many flow controls here, it may be usefull to
> mention which one we are talking and
> when. In my understanding following flow controls are being mentioned here.
>
> a. 802.3x : Useful  on recieve (wrt medium side) side FIFOs. In the context
> of 10 vs 9.58460 I do
>     not appreciate, how it can help.
> b. Transmit side PHY to MAC flow control either using COL (as I suggested)
> or HOLD (as Dan has suggested).
>     This is applicable when PHY is at 9.58460 and MAC at 10.
> c. Receive side MAC to PHY flow control. Applicable if one decides to have
> 9.5846 as MAC speed and 10 as PHY. I am
>     not sure if, ever, this has been context, though.
>
> Is there anything else we are talking ?
>
> Thanks,
> Tripathi.

--

Best Regards,
Rich

-------------------------------------------------------------
Richard Taborek Sr.    Tel: 650 210 8800 x101 or 408 370 9233
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