Subject: RE: [mobile-ip] RFC3012 interpretation yet again

From: "Lipford, Mark" <[email-masked]>
Date: Tue, 23 Oct 2001 20:51:36 -0500

As someone that has to implement this we strongly support this
recommendation

		-----Original Message-----
		From:	[email-masked] [mailto:[email-masked]]
		Sent:	Tuesday, October 23, 2001 6:15 PM
		To:	[email-masked]
		Subject:	[mobile-ip] RFC3012 interpretation yet again

		I'd like to encourage the working group and/or
		draft authors to come to some sort of official decision
		about the proper interpretation of section 8 of this RFC,
		and make this decision public.

		Basically, this would involve an announcement on this list
		and a publication of an errata on the RFC editor pages.

		The sooner such an errata is made public and official
		the better.  Otherwise there is a chance that both
		interpretations may be deployed.

		Thanks in advance,
		Mike

---

From: "Basavaraj Patil" <[email-masked]>
Date: Tue, 23 Oct 2001 22:08:40 -0500

We will go ahead with the revisions to the current RFC3012 to clarify
the issue (no ambiguities and scope for misinterpretation) about computing
the authenticator based on the challenge. 

If you believe there are other issues as well (based on implementation
experience) with this RFC, now would be the time to raise them.

We hope to have this done fairly quickly.

Regards,
-Basavaraj 

> From: [email-masked]
> [mailto:[email-masked]]On Behalf Of Lipford, Mark
> Sent: Tuesday, October 23, 2001 8:52 PM
> To: [email-masked]'
> Subject: RE: [mobile-ip] RFC3012 interpretation yet again
> 
>

---

From: Luca Salgarelli <[email-masked]>
Date: Wed, 24 Oct 2001 09:28:18 -0400

Basavaraj, Pat, Charlie,

actually I do have a request for clarification on another point of RFC3012.

In secion 3.1, page 4 the RFC says:

   A successful Registration Reply from the Foreign Agent MAY include a
   new Challenge value (see section 3.3).  The Mobile Node MAY use
   either the value found in the latest Advertisement, or the one found
   in the last Registration Reply from the Foreign Agent.  This approach
   enables the Mobile Node to make use of the challenge without having
   to wait for advertisements.

   A Mobile Node might receive an UNKNOWN_CHALLENGE error (see section
   9) if it moves to a new Foreign Agent that cannot validate the
   challenge provided in the Registration Request.  In such instances,
   the Mobile Node MUST use a new Challenge value in any new
   registration, obtained either from an Agent Advertisement, or from a
   Challenge extension to the Registration Reply containing the error.

So it states that the MN MUST use a Challenge from an unsuccessful Reply.

However, in section 3.2, page 5, it also says:

   The Foreign Agent MUST NOT accept any Challenge in the Registration
   Request unless it was offered in last successful Registration Reply
   issued to the Mobile Node, or else advertised as one of the last

Which seems to go against what stated above.

In general, I think that there is the need to clarify if the FA should or
should not include a Challenge in an unsuccessful Registration Reply. If
the FA should include it, than it should be clarified whether the MN is or
is not allowed to use a Challenge obtained from an unsuccessful Reg. Reply.

Thanks
Luca