RE: Local Fault/Remote Fault
This was so lightly treated in the adopted presentation, that I missed
inhibiting frame transmission because of received RF as an RS function.
Shimon Muller has proposed a complete rewrite of 46.2.6 that fixes the
problem along with a number of others (e.g., how is the fault condition
cleared). As clause editor I will recommend accepting Shimon's comment next
week (with minor edits).
--Bob Grow
-----Original Message-----
From: Rich Taborek [mailto:rtaborek@xxxxxxxxxxxxx]
Sent: Tuesday, January 02, 2001 3:39 PM
To: HSSG
Subject: Re: Local Fault/Remote Fault
Eric,
This is worth a comment, because it is what we voted in as a baseline
proposal in Tampa in taborek_2_1100.pdf (see page 5 and others). I don't
believe that a unidirectional Ethernet link is of any value to the user.
Therefore, a RF condition should cause Link Status to be set to Fail in
the RF transmitting and receiving devices. In addition, how else is the
failing link direction going to get a chance to heal if it broke while
it was receiving, at best, only Idles, and at worst, Idles with minimum
IPGs.
Happy Holidays,
Rich
--
Eric Lynskey wrote:
>
> Rich,
>
> This is something I've been trying to figure out for a while. Perhaps you
> can shed some light on this.
>
> > 3. The RS layer is where the Local Fault Pulse Ordered Set is
> > processed. The RS layer is the only place that a Remote
> > Fault Pulse Ordered Set can be generated. If an RS receives
> > a Local Fault Pulse Ordered Set it must stop sending packets
> > and begin sending alternating columns of Idles and Remote
> > Fault Pulse Ordered Sets. If an RS receives a Remote Fault
> > Pulse Ordered Set, it must stop sending packets and send
> > only Idles.
>
> I cannot find any indication that if an RS receives a Remote Fault Pulse
> Ordered Set, that it must stop sending packets and send Idles. As far as
I
> can tell, all Clause 46 says about reception of Remote Fault messages is
> that this "indicates that the link partner DTE has detected a fault (and
> consequently will not transmit frames." I know the end paranthesis is
> missing, but I take that to simply mean that the link partner will not
> transmit frames, but it says nothing about the local device inhibiting
> transmission of MAC frames. Later on, it describes what happens when the
> local device receives local fault messages, but nothing about remote fault
> messages. What exactly was your intention with this? Should the local
> device stop transmitting frames when it receives Remote Fault status
> messages? It seems as if this is so, and I'll submit a comment about it
if
> that is correct.
>
> Eric Lynskey
> UNH InterOperability Lab
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