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RE: Last call - RSVP problems
You have brought up a good point.
Is there any ongoing effort to standardize
the signalling mechanism on the optical side.
Namely in-band SONET-DCC OH bytes vs out-of-band
Ehternet vs in-band IP-over-SONET data plane etc.
>From: Dimitrios Pendarakis <DPendarakis@tellium.com>
>To: "'Jonathan Lang'" <firstname.lastname@example.org>, "'Fong Liaw'"
><email@example.com>, "'suresh Katukam'" <firstname.lastname@example.org>,
>CC: "'Jennifer Yates'" <email@example.com>, mpls@UU.NET,
>Subject: RE: Last call - RSVP problems
>Date: Fri, 25 May 2001 18:16:12 -0400
>One point to consider is that the signaling control
>channel might be realized over a different link layer
>than LMP. For example, LMP might be running in-fiber
>over SONET/SDH overhead bytes, while RSVP is running
>over an out-of-band network such a shared Ethernet.
>RSVP Hello allows independent detection of signaling
>channel failure, so it's a useful option to keep.
> > -----Original Message-----
> > From: Jonathan Lang [mailto:firstname.lastname@example.org]
> > Sent: Friday, May 25, 2001 5:30 PM
> > To: 'Fong Liaw'; 'suresh Katukam'; email@example.com
> > Cc: 'Jennifer Yates'; mpls@UU.NET; firstname.lastname@example.org
> > Subject: RE: Last call - RSVP problems
> > Fong,
> > <snip>
> > > Same as (2), any proposals that remove the refresh mechanism
> > > is going to be difficult to prove that all cases are covered.
> > >
> > > Instead, we (will) recommend the following in OIF UNI document:
> > >
> > > Use RSVP Hello to detect control channel failure.
> > Why wouldn't you use the LMP Hello to detect control channel
> > failure? This
> > is exactly what it is designed for. From
> > draft-ietf-mpls-lsp-tunnel-08.txt,
> > "This (RSVP Hello) mechanism is intended to be used when
> > notification of
> > link layer
> > failures is not available and unnumbered links are not
> > used, or when
> > the failure detection mechanisms provided by the link layer are not
> > sufficient for timely node failure detection."
> > > If a control channel failure is detected, LSPs states
> > > are maintained as if a node continues to receive
> > > RSVP refresh message from the failed control channel.
> > > The recommended Hello timer will be in second range,
> > > instead of ms range specified in RSVP-TE draft.
> > >
> > > If a control channel failed permanently, manual intervention
> > > may be required. This is to be studied.
> > >
> > > p.s The text is currently being drafted as we type.
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