Subject: FR OAM (was RE: PWE3 Arch/CW & RTP Order (Rough Consesus?))

From: "Mark Seery" <[email-masked]>
Date: Mon, 12 May 2003 19:49:22 -0700

Tom,

[SNIP]

> Shahram: FR does not have proper OAM. So we shouldn't base MPLS on
deficiencies of FR. <

> Tom : Well, this is the first that I have heard of this. Given how long FR
has been implemented, I would hope that if it really were, that dissatified
SPs would have complained. <

Tom and Shahram both make good points. Perhaps expanding on Shahram's short
assertion may help.

Technically, [FR OAM] FRF.19 does not provide the functionality that ATM OAM
does, this is acknowledged by primary authors of FRF.19. FR OAM was not
standardized until around 2000? and not sure it has even been widely
implemented. So bare in mind it is hard to complain about something that was
not available for most of Frame Relay's history (that's assuming it is even
today).

FRF.19 was focused on CPE-to-CPE service quality measurements (apparently
some small amount of NNI use has been found as well) seeing the network as
being mostly transparent - for example FR/ATM OAM interworking spec. has not
been created. ATM OAM has different focus and capabilities.

This all begs the question that if OAM is so important, then how did Frame
Relay become so successful without it? Well ultimately that is a question
for a service provider to answer, I would just observe that a number of SPs
view FR as a best effort service. Undoubtedly QoS is part of that
assessment, but there are probably other considerations as well; and of
course some SPs view a strong OAM capability as being key to being offer
strong QoS.

I suggest SPs define what OAM requirements they want/need for PWE3 and the
group goes from there. Arguing about FR OAM is not likely to prove
constructive or instructive given that it has been none-existent, for all
intents and purposes, for most of FR's history.

Perhaps one thing for the group to consider is whether PWE-based services
are intended to be viewed as having similar quality to Frame Relay, or
similar quality to ATM services. Frame Relay has essentially, in the
enterprise data services context, essentially been a service interface, and
not a service transport - something else to bare in mind.

Mark