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Re: [EFM] flow control in 802.3


In 10GE, we're adding a mode to the MAC that increases the IPG
based on the length of the preceding packet to lower the overall
data rate - ifsStretchMode. It is currently only applicable to
the 10GE MAC when connected to the medium via a WAN PHY but I
don't believe there is anything that would not allow this to be
extended for other purposes (other than a vote of less than 75%
that is :)

Ben Brown

> All,
> Is there a way to transmit flow control information across an MII interface from the PHY direction to the MAC ? If yes could someone point me to the pertaining clause of 802.3 ?
> In other words, let's assume that a PHY for some reason or other can only transmit at 3Mbps while information to that PHY flows at 10Mbps. How can the PHY tell the MAC to stop sending ? I saw some presentations related to 10 Gigabit Ethernet that proposed various mechanisms but I do not know if anything was adopted.
> Any help would be appreciated.
> Thanks,
> Marc Kimpe
> Adtran

Benjamin Brown
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