Re: [v6ops] RFC6459 "IPv6 in 3GPP"

What do you mean by 'not very common'?  Is it little common in some 
small place?

PD from ll src: I think the DHCP spec does not tell whether it could be 
an LL or a GUA.  I asked on the DHC WG email list.  The operator seems 
to prefer to hear the DHCP Solicit to be issued from a GUA.

Le 11/07/2017 à 11:49, Erik Kline a écrit :
> Is your carrier known to support PD?  I don't think it's very common
> yet.  Also, shouldn't you be sending your PD request from a link-local
> source address?
> 
> On 11 July 2017 at 18:28, Alexandre Petrescu
> <alexandre.petrescu@gmail.com> wrote:
>>
>>
>> Le 11/07/2017 à 08:51, mohamed.boucadair@orange.com a écrit :
>>>
>>> Hi Alex,
>>>
>>> Please see inline.
>>>
>>> Cheers,
>>> Med
>>>
>>>> -----Message d'origine-----
>>>> De : Alexandre Petrescu [mailto:alexandre.petrescu@gmail.com]
>>>> Envoyé : lundi 10 juillet 2017 18:28
>>>> À : BOUCADAIR Mohamed IMT/OLN; v6ops@ietf.org
>>>> Objet : Re: [v6ops] RFC6459 "IPv6 in 3GPP" - the IID in the LL address
>>>>
>>>>
>>>>
>>>> Le 10/07/2017 à 16:58, mohamed.boucadair@orange.com a écrit :
>>>>>
>>>>> Re-,
>>>>>
>>>>> Please see inline.
>>>>>
>>>>> Cheers,
>>>>> Med
>>>>>
>>>>>> -----Message d'origine-----
>>>>>> De : Alexandre Petrescu [mailto:alexandre.petrescu@gmail.com]
>>>>>> Envoyé : lundi 10 juillet 2017 16:46
>>>>>> À : BOUCADAIR Mohamed IMT/OLN; v6ops@ietf.org
>>>>>> Objet : Re: [v6ops] RFC6459 "IPv6 in 3GPP" - the IID in the LL address
>>>>>>
>>>>>>
>>>>>>
>>>>>> Le 10/07/2017 à 16:16, mohamed.boucadair@orange.com a écrit :
>>>>>>>
>>>>>>> Alex,
>>>>>>>
>>>>>>> I'm focusing on this part of your answer.
>>>>>>>
>>>>>>> Please see inline.
>>>>>>>
>>>>>>> Cheers, Med
>>>>>>>
>>>>>>>> -----Message d'origine----- De : Alexandre Petrescu
>>>>>>>> [mailto:alexandre.petrescu@gmail.com] Envoyé : lundi 10 juillet
>>>>>>>> 2017 15:51 À : BOUCADAIR Mohamed IMT/OLN; v6ops@ietf.org Objet :
>>>>>>>> Re: [v6ops] RFC6459 "IPv6 in 3GPP" - the IID in the LL address
>>>>>>>>
>>>>>>>> Med,
>>>>>>>>
>>>>>>>>
>>>>>>>>>> This has consequences on privacy, and may impact
>>>>>>>>>> interoperability when DHCPv6-PD is used later in the process.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> [Med] I don't follow you here. There is no privacy concern out
>>>>>>>>> there. The IID used when forming a global IPv6 address will be
>>>>>>>>> selected by the terminal; no assumption is made about those
>>>>>>>>> bits.
>>>>>>>>
>>>>>>>>
>>>>>>>> There is a privacy concern: if the operator enforces the UE to
>>>>>>>> always use the network-assigned IID then that UE is trackable.
>>>>>>>>
>>>>>>>
>>>>>>> [Med] I'm not sure what you mean by "trackable" in this context. If
>>>>>>> you mean that "a UE can be identified by the network", then an UE is
>>>>>>> always identified by the network it connects to!
>>>>>>
>>>>>>
>>>>>> YEs, and I thought that is a device-specific identifier like the IMEI,
>>>>>> not the link-local address.
>>>>>>
>>>>>>> At the IP level, an UE is identified by the bits of the IPv6 prefix,
>>>>>>>     not IID bits.
>>>>>>
>>>>>>
>>>>>> Well - by the IP address.
>>>>>
>>>>>
>>>>> [Med] No. I reiterate my answer: it is identified by the prefix not the
>>>>
>>>> full IPv6 address.  Policies at the network are enforced based on the
>>>> prefix, not the full IPv6 address.
>>>>>
>>>>>
>>>>>>
>>>>>>> Further, a network does not need IP-related information to identify
>>>>>>> an UE.
>>>>>>
>>>>>>
>>>>>> I agree, so why does it want to impose an IID to the UE?
>>>>>
>>>>>
>>>>> [Med] This is an optimization to avoid DAD.
>>>>
>>>>
>>>> Ok about LL, but how about the GUA?
>>>
>>>
>>> [Med] No problem at that front either (reading from the 3GPP spec):
>>>
>>> ==
>>> Since the GGSN guarantees that the Prefix is unique, the MS does not need
>>> to perform any Duplicate Address Detection on addresses it creates.
>>> ==
>>>
>>>     If the network uses a GUA same as
>>>>
>>>> the UE then there should be DAD for that GUA.
>>>
>>>
>>> [Med] Idem as above, the spec is clear:
>>>
>>> ==
>>> The GGSN shall not generate any globally unique IPv6 addresses for itself
>>> using the Prefix assigned to the MS in the Router Advertisement.
>>> ==
>>>
>>>>
>>>> I dont think there is any spec that tells that the network MUST NOT
>>>> assign a GUA on its interface towards the UE.
>>>
>>>
>>> [Med] See for example, 3GPP TS. 29.061
>>>
>>>>
>>>>
>>>>
>>>>>>> I still don't see any privacy concern in supplying an IID to an UE
>>>>>>> to be used for forming its link-local address.
>>>>>>
>>>>>>
>>>>>> Err...
>>>>>>
>>>>>> It's because the supplied IID is very much like an IEEE MAC 48bit
>>>>>> address.
>>>>>
>>>>>
>>>>> [Med] This is a link-local address not a GUA. So, not sure to understand
>>>>
>>>> your point.
>>>>
>>>> I can understand your point about GUA privacy vs LL privacy.
>>>
>>>
>>> [Med] OK.
>>
>>
>> Med - why there is no answer to my DHCPv6 PD Solicit?  I am using a GUA
>> without the IID from the operator.
>>
>> Alex
>>
>>
>>>
>>
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