The MPLS WG Archive

["Doug Degan" <doug_degan@hotmail.com>]

ping, thanks for the quick answer but looks like I didn't understand it or
wasn't clear enough in my question :

I was refering to the time of failure. not to the time after failure when
the bypass is being used already.

I assume bypass LSP is ready, and primary LSP is protected by it.
then a failure occures somewhere between the PLR and the MP.
the MP will probably get PATH-TEAR message because of it (also all the
routers between the failure and the MP will get it) but the MP shouldn't
send it downstream!!! because the lsp is not going to be teared from the MP
to the Egress.

to this problem I didn't find solution in the draft.

thanks again.
----- Original Message -----
From: "Ping Pan" <pingpan@juniper.net>
To: "Doug Degan" <doug_degan@hotmail.com>
Cc: <mpls@UU.NET>
Sent: Sunday, February 10, 2002 8:52 PM
Subject: Re: fast-reroute question


> Doug Degan wrote:
>
> > hi.
> >
> > I have another question regarding pan's draft in BYPASS method:
> >
> > 1) how does upstream routers act upon receiving of PATH TEAR message?
> > there should be different activity between normal router and MP - but
> > how does a router know he is active MP for a given LSP?
> >
> > if he does - he shouldn't tear it, but if he is just transit router - he
> > should tear it!
> >
>
>
> When there is a network problem, the protected LSPs will use the bypass
> LSP, and initiate Path Messages that will merge at MP. At this point,
> it's a bunch of RSVP sessions using SE. When you get a PathTear, just
> act according to what RSVP had defined.... kill the session and
> associated branches.
>
> - Ping
>
>
> >
> >
> > thanks in advance.
> >
> > doug.
> >
> >
> >
>
>
>