Re: [mpls] draft-fang-mpls-label-forwarding-no-swap - how much does it really save?

Shahram Davari <davari@broadcom.com> Thu, 23 July 2015 21:04 UTC

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From: Shahram Davari <davari@broadcom.com>
To: "Andrew G. Malis" <agmalis@gmail.com>
Thread-Topic: [mpls] draft-fang-mpls-label-forwarding-no-swap - how much does it really save?
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Date: Thu, 23 Jul 2015 21:04:50 +0000
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Subject: Re: [mpls] draft-fang-mpls-label-forwarding-no-swap - how much does it really save?
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That’s was my understanding too that TTL and EXP work as usual.

Thx
Shahram

From: Andrew G. Malis [mailto:agmalis@gmail.com]
Sent: Thursday, July 23, 2015 1:33 PM
To: Shahram Davari
Cc: Loa Andersson; Andrew Qu; Alexander Vainshtein; Stewart Bryant; S. Davari; mpls@ietf.org
Subject: Re: [mpls] draft-fang-mpls-label-forwarding-no-swap - how much does it really save?

Sharam,

The point was made during the meeting that on the wire, "no swap" (but still decrement TTL, etc.) is indistinguishable from "swap to the same label". So this really is a local optimization in the switch, and not subject to standardization.

Cheers,
Andy

On Thu, Jul 23, 2015 at 7:18 PM, Shahram Davari <davari@broadcom.com<mailto:davari@broadcom.com>> wrote:
I thought the idea was to decrement TTL and consider EXP bits for queuing and count as a hop so you can do OAM, etc.. Basically swap to itself.

Thx
Shahram