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Re: Remote Faults in RS

Hi Jennifer,

Your second assumption is correct. Clause 46.3.4 last
last para bullet "b)" states that link_Fault = Local Fault then
RS shall continously generate Remote Fault Sequence ordered_sets.

And then in Clause the last para allows Sequence 
ordered sets to be deleted but only if PCS receives 2 consecutive
Sequence ordered sets. Now, since RS is sending continously
RF Sequence ordered sets the PCS should not have any issue
getting two consecutive RF Sequence ordered sets and deleting one.


At 03:15 PM 06/05/2001 -0700, Sanati, Jennifer wrote:
>Hello everyone,
>   I would like some clarification regarding the format of remote faults
>that are generated during transmission in the reconciliation sublayer and
>presented to the 64b/66b 10GBase-R PCS.
>Referring to an excerpt from a previous IEEE reflector discussion by Stephen
>Finch on Fri, 29 Dec 2000, he states...
>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.
>Is the underlined statement still valid?  If a LF is received at the RS, is
>it then translated to a RF during TX and flagged by sending a stream of
>altermating columns of Idles and Sequence Ordered Sets?
>such as,     /I   /Q   /I   /Q   /I
>                 /I   /Q   /I   /Q   /I
>           	     /I   /Q   /I   /Q   /I
>                 /I   /Q   /I   /Q   /I
>If this is a correct assumption, for WIS rate control methods, is it correct
>that after the minimum IPG, it is only valid to delete Idles and pass on the
>Sequence Ordered Sets? 
>   The previous question is pertinent only if the above data stream can
>occur as a possible input to the TX 64b/66b PCS.  If, instead, a RF triggers
>a "relatively long" string of consecutive Sequence Ordered Sets, 
>such as,    /Q   /Q  . . . .   /Q   /Q
>      	    /Q   /Q  . . . .   /Q   /Q
>                /Q   /Q  . . . .   /Q   /Q
>                /Q   /Q  . . . .   /Q   /Q
>then WIS rate control would be much easier to design for.
>I would appreciate any input regarding these detailed matters.
>Jennifer Sanati