[Softwires] MAP & 4rd-U - Preserving freedom of subnet-prefixes (V octet)

Rémi Després <despres.remi@laposte.net> Mon, 06 February 2012 08:24 UTC

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Subject: [Softwires] MAP & 4rd-U - Preserving freedom of subnet-prefixes (V octet)
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Le 2012-02-05 à 10:05, Ole Trøan a écrit :

>>>  what happens with 4rd-U if the End-user IPv6 prefix is e.g a /96?
>>> and the V-bits are not adhered to?
>> If the End-user doesn't support 4rd-U, nothing to be said. 
>> If 4rd-U is enabled, any prefix longer than /64 that matches a Mapping rule MUST have the V octet.
>> If any you have a case where this isn't sufficient, I will look at it.
> MAP is more flexible with regards to not depending on the V octet.

(a) Which flexibility? To do what? 

(b) Do you negate that:
- with MAP as is, an IPv6 site may have to change its assignment of subnet prefixes to support MAP
- This is never needed with 4rd-U, thanks to the V octet.