Re: [mpls] Determining proper TTL of a tunnel in Fast LSP-alert Mechanism

Sriganesh Kini <sriganesh.kini@ericsson.com> Mon, 26 July 2010 21:43 UTC

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From: Sriganesh Kini <sriganesh.kini@ericsson.com>
To: Greg Mirsky <gregimirsky@gmail.com>, Autumn Liu <autumn.liu@ericsson.com>, "mpls@ietf.org" <mpls@ietf.org>
Date: Mon, 26 Jul 2010 17:43:31 -0400
Thread-Topic: Determining proper TTL of a tunnel in Fast LSP-alert Mechanism
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Subject: Re: [mpls] Determining proper TTL of a tunnel in Fast LSP-alert Mechanism
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Greg,

I wouldn't interpret that as invalidating the requirement. Those are thoughts on potential workarounds and should be considered only for scenarios that have LSRs that don't support the functionality.

Thanks

- Sri



________________________________
From: Greg Mirsky [mailto:gregimirsky@gmail.com]
Sent: Monday, July 26, 2010 1:53 PM
To: Autumn Liu; Sriganesh Kini; mpls@ietf.org
Subject: Determining proper TTL of a tunnel in Fast LSP-alert Mechanism

Dear Authors,
the Section 3.2.2 states new requirement which ends with the sentence:
"An LSP label on the forwarded packet MUST continue to have TTL set to 1."
But at the same time, in Section 6 when outlining direction for future work, it is said that in heterogeneous environment value of TTL must be determined by each node that supports the Fast LSP-alert mechanism. Does that scenario invalidates the requirement put forward in Section 3.2.2?

Regards,
Greg