Re: 64share v2

Le 11/11/2020 à 10:31, Lorenzo Colitti a écrit :
> On Wed, Nov 11, 2020 at 9:01 AM Brian E Carpenter 
> <brian.e.carpenter@gmail.com <mailto:brian.e.carpenter@gmail.com>>
> wrote:
> 
> This memo requests the 3GPP to change this requirement to allow any 
> prefix size less than or equal to 64 be advertised by the 3GPP 
> gateway RA. It also, for this purpose only, overrides the 
> implication of [RFC 4291] and [RFC 4861] that subnet prefixes in RAs
> are always /64.
> 
> 
> I think that if we want to gain consensus on this document, we should
>  avoid overriding/updating/touching RFC 4291.
> 
> Fortunately I don't think we need to. We can simply do as Ole
> suggested and have the RA contain both the /64 PIO and a new option
> conveying the delegated prefix. We need to continue to maintain the
> /64 PIO anyway.

I can say that I like such a proposal because it involves a prefix
delegation concept in RA, an RA-PD, and I co-authored a draft about it
and there might be an implementation hidden somewhere in some archives.

I must say I am happy to hear that.

At the same time, I think GGSN would not implement RA-PD.  The proposal
64share-v2 seems by just modifying the existing /64 parameter in the RA.
  To remind, it was said "a tweak of the 3gpp spec to allow RA < 64 and a
UE mechanism to break that prefix into many 64s".

It says a tweak in spec and an UE mechanism.

It does not say a GGSN mechanism.

So, while we can indeed discuss many possible ways out, I would
re-verify what we want to do.

> If we don't, otherwise existing devices won't get IPv6 connectivity,
> since they know that a PIO with a /60 isn't valid for autoconf (even
> if A=1), because for global space, IIDs are always 64 bits long.

I partially disagree.

Alex

> 
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