[Softwires] Objection to 4rd-U made in Softwire meeting understood to be invalid

Rémi Després <despres.remi@laposte.net> Tue, 15 November 2011 23:11 UTC

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Date: Wed, 16 Nov 2011 07:09:59 +0800
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Subject: [Softwires] Objection to 4rd-U made in Softwire meeting understood to be invalid
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In the Softwire meeting of Monday, the key argument against the 4rd unified approach (4rd-U) was that *Because checksum neutrality of addresses is part of 4rd-U, it would allegedly cause "address spreading" (addresses used between a pair of hosts would vary)*. 
You had a slide asserting it, and the argument was taken as granted, and important, in verbal comments from Mark Townsley and Dave Thaler.
I forcefully declared that this was technically false.
Since no time has been granted to explain, I invited anyone in doubt to contact me for explanations. 
Thanks for having taken the time to do it.

Following our discussion of yesterday, I think you now understand that, as I said:
- *TCP/UDP checksum neutrality of addresses DOES NOT interfere in any way with stability of addresses between host pairs*.
- Consequently, the key argument of the meeting against 4rd-U is invalid.

Since there is no more Softwire session in IETF 82, I will appreciate if you acknowledge it now on this mailing list.