Re: Remote Link Down
Henry,
GbE supports remote fault indication via the Auto-Negotiation protocol and the
Remote Fault bit in the base register. At the very least, the same functionality
should be brought forward to 10 GbE. In addition, I have proposed an
Auto-Negotiation scheme for gigabit serial links which works on the the basis of
link pulses ala its parallel copper counterparts. This scheme allows enables
Remote Fault signaling even if the link is not capable of supporting normal
code-group transfer (required for 1 GbE AN and RF signaling). It also allows
functions such as speed negotiation over optical links (e.g. 1/10 GbE link
operation). The presentation introducing this scheme is located at:
http://grouper.ieee.org/groups/802/3/10G_study/public/june99/taborek_3_0699.pdf
Best Regards,
Rich
--
Henry Ngai wrote:
> Quite a while back there was some talk on remote link down information in
> 802.3. If we can work that into the 10G Ethernet PHY specification, would
> that satisfy your requirement? Since we don't use link pulse, may be we can
> put in something in the line coding scheme to indicate remote link status?
> The original remote link down function basically uses the link pulse to
> inform the MAC that the up link is failing. Even if ping fails because of
> failing optics on the up link, we can still get the link status on the up
> link from the other MAC. What do you think?
>
> Thanks!
> Henry Ngai
-------------------------------------------------------------
Richard Taborek Sr. Tel: 650 210 8800 x101 or 408 370 9233
Principal Architect Fax: 650 940 1898 or 408 374 3645
Transcendata, Inc. Email: rtaborek@transcendata.com
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