Re: More comments (clauses 49 & 46)
Hi Rich,
I agree on that we need to keep the undetected packet error rate as low as
possible. Before you guys decide to trash a packet when RS sees an error
logically comes after the EOP( which is new ) , we need to know in what
conditions this will happen as a result of packet data error? When it happens,
what's the chance that those packets will pass CRC check?
I don't have the exactly number here. But I believe the chance to pass
error packets if we decide not to trash those packets is much lower than
the chance to drop good packets if we decide to trash those packets, in this
particular case. Unless we know that the /E/ coming after /T/ can only happen
when there is an error in the packet data.
Regards,
Louis
Rich Taborek wrote:
> Louis,
>
> I don't agree. I believe that the MAC must trash the packet regardless
> of good CRC because the MAC has no clue as to whether or not an 8b/10b
> or 64b/66b or combination or multiples of the above are present. I
> maintain that in all cases, it's NOT OK for the RS to treat it as a good
> packet in order to keep the undetected packet error rate down. Note that
> we're splitting hairs here since for 8b/10b in most cases, both 8b/10b
> and the MAC's CRC check will call the packet bad.
>
> Best Regards,
> Rich
>
> --
>
> Louis Lin wrote:
> >
> > Hi Rich,
> >
> > In your case of
> >
> > lane 0: DD
> > lane 1: DT
> > lane 2: DI
> > lane 3: DE
> >
> > or all the case of /E/ been seen in the same column as /T/ but after /T/.
> >
> > If it's from 64/66B PCS, I don't think we need to declare it as a
> > bad packet. If it's from 8B/10B PCS and the /E/ is a result of the
> > data. I think the FCS checker in the MAC will trash the packet.
> > In either case, it's ok for RS to treat it as a good packet.
> >
> > Regards,
> >
> > Louis
>
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