Subject: RE: draft-nadeau-pwe3-oam-msg-map-04.txt

From: [email-masked]
Date: Wed, 24 Mar 2004 14:22:46 -0000

Folks,

draft-nadeau-pwe3-oam-msg-map-04 states in the introduction "This document describes ... how faults detected in pseudo-wires are mapped to OAM messages native to the emulated services and vice versa".

I can see the need to map OAM up the network stack from the server layer OAM (e.g. a MPLS server layer) to the client AC OAM (e.g. an ATM client layer) but why is there a need to map OAM down the network stack from AC OAM to server layer OAM?

For example, today there are client/server relationships where ATM VPs (the client) are transported over SDH VC_4s (the server), defects in the SDH server layer are mapped upwards to the ATM client layer.  However defects in the ATM client layer are not mapped down to the SDH server layer.  This is because defects in the client layer do not affect the server layer whereas defects in the server layer do affect the client layer.

Thanks
Ben