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Re: Comments on P802.3ae/D1.1

Please see my comment below to the question related to the
MIB counters aSectionCVs and aPathCVs.

At 11:18 PM 11/12/00 -0500, Ben Brown wrote:

>Here are some comments on the latest release of the draft.
>Comments from all of the clauses are combined. This is limited
>to those comments that weren't made (or heard) last week
>(I think).


>, page 58 &, page 60:
>  aSectionCVs can be incremented for each errored bit in
>  the B1 octet (the counter is incremented by a value
>  between 0 & 8 for each SONET frame).
>  aPathCVs can be incremented when any bit in the B3
>  octet is in error (the counter is incremented by a
>  value between 0 & 1 for each SONET frame).
>  Why are these counters handled differently? I heard
>  something about this being the way they are defined in
>  SONET/SDH. Can I get a hard reference to those definitions
>  if this is indeed the case?

aSectionCVs counts "BIP-N errors" while aPathCVs counts "block errors".

You can find the definition of BIP-N error and block error in
ANSI T1.231-1997:

Sections "Error Detection Code", "BIP-N Error",
and "Block Error (BE)".

It also helps to read "BER and EDC Thresholds for SES" in Annex C of
ANSI T1.231-1997. It explains why SES threshold values for Section/Line
and Path are based on different definitions. In short, definitions
are different for historical reasons.