Subject: RE: DAD in node requirements draft

From: "Peter Barany" <[email-masked]>
Date: Tue, 25 Mar 2003 14:04:11 -0600

There may be some terminology/semantics that need to be clarified regarding
my usage of the term "link". What I meant to convey was that for 3GPP
(UMTS), a primary PDP context (and its associated secondary PDP contexts)
are treated as a single IPv6 "link". But the GGSN views each primary PDP
context as a single "subnet". Therefore, DAD is not required. Similar for
3GPP2 (cdma2000), except PPP is used, etc.  

Pete

-----Original Message-----
From: Ole Troan [mailto:[email-masked]]
Sent: Tuesday, March 25, 2003 1:29 PM
To: Barany, Peter [RICH1:2H16:EXCH]
Cc: Mika Liljeberg; [email-masked]; [email-masked];
[email-masked]
Subject: Re: DAD in node requirements draft

[...]

> During 3GPP (UMTS) work on PDP context activation, it was agreed to make
the
> /64 prefix unique per primary (and associated secondary) PDP contexts so
> that DAD would not have to be performed (particularly since privacy
> addresses are specified for use in 3GPP). See RFC 3314 and, I believe, 3G
TS
> 23.060 (and/or maybe another document in the 3GPP 24 series).
>
> 3GPP2 (cdma2000) uses PPP and not a PDP context. In IS-835-B it is stated
> that the /64 prefix(es) must be unique to that PPP link ... again avoiding
> DAD when privacy addresses are used.

requiring that a /64 is unique on a link does not avoid DAD.
doesn't the 3GPP specs restrict one end of the link to not use any
addresses from the prefix, if so DAD is not needed.

> Since the IETF IPv6 WG is in the process of updating the IPv6 PPP RFC 2472
> (more specifically IPV6CP), my question is: What changes are being planned
> to that RFC? Do any of these changes pertain to the granularity/uniqueness
> of the /64 prefix? Thanks.

the only thing I can see requiring an update is that the value of
DupAddrDetectTransmits should default to 1 not 0.

you can turn off DAD in your environment if you know you don't need
it.

/ot

---

From: "Peter Barany" <[email-masked]>
Date: Tue, 25 Mar 2003 14:23:29 -0600

Also, I do not believe the change you suggest below for IPv6 over PPPbis
would be needed for 3GPP2 (cdma2000), which uses PPP for MS to PDSN
connectivity.

Regards,

Pete 

-----Original Message-----
From: Ole Troan [mailto:[email-masked]]
Sent: Tuesday, March 25, 2003 1:29 PM
To: Barany, Peter [RICH1:2H16:EXCH]
Cc: Mika Liljeberg; [email-masked]; [email-masked];
[email-masked]

[...]

the
TS

/ot