Re: [v6ops] RFC6459 "IPv6 in 3GPP" - the IID in the LL address

[Gert Doering <[e-mail]>]

Hi,

On Mon, Jul 10, 2017 at 06:27:47PM +0200, Alexandre Petrescu wrote:
> > [Med] This is an optimization to avoid DAD.
> 
> Ok about LL, but how about the GUA?  If the network uses a GUA same as 
> the UE then there should be DAD for that GUA.

The network is not using addresses out of the /64 assigned to the handset.

> I dont think there is any spec that tells that the network MUST NOT 
> assign a GUA on its interface towards the UE.

Do not "think" when 3GPP specs are confirmed - just check.  This is
(as has been explained before) standardized quite well.

[..]
> Some packets with LLs as src have been witnessed in the Internet at large.

This is a bug in all the forwarding entities on the path and needs to be
fixed.

> Some times some UE apps may put a link-local address in 
> application-layer payloads.  Some protocols do it too (e.g. OSPF puts 
> LLs in LSAs, DHCP puts interface IDs and LLs in payloads, etc).

This would be a bug in the application, which would need to be fixed.

(Nobody stated, btw, that you'll get the *same* IID on every PDP setup...)

> >   It is guaranteed unique, so it can also be used to track.
> > [Med] to be tracked by whom?
> By the operator, and by other parties outside the operator network.

The operator knows where you are and what you do, without having to refer
to LLAs.

Gert Doering
        -- NetMaster
-- 
have you enabled IPv6 on something today...?

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