Re: [Softwires] Unified proposal for stateless IPv4 Residual Deployments (4rd-U) - Contributors?

Ole Troan <> Tue, 29 November 2011 16:15 UTC

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Subject: Re: [Softwires] Unified proposal for stateless IPv4 Residual Deployments (4rd-U) - Contributors?
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> For those who attended the Softwire session in Taipei, please note that the serious objection against 4rd-U expressed by several participants during the meeting has been, soon after, acknowledged to be invalid (
> Also, other (less important) objections have been answered in, without reaction so far. 

I do not think that's a fair representation.
the main objection to 4rd-u is that it is 'just another translation' solution. how many do we need? it doesn't appear to offer any benefits compared to the already specified solution. as it stands it will just result in 3 ways of doing the same thing, instead of 2.

the topic discussed in softwires, wasn't the main objection. as far as I can see, "checksum neutrality" does not offer any advantages over incrementally updating the L4 checksum. every node doing this will have to look into the L4 header anyway.