Subject: [mobile-ip] Drafts on MIP extensions to support DNS

From: "Jayshree Bharatia"<[email-masked]>
Date: Wed, 6 Mar 2002 16:05:15 -0600

Hello,
 
We have recently submitted two new drafts,
http://search.ietf.org/internet-drafts/draft-bharatia-mobileip-v4-dns-ext-00
.txt
<http://search.ietf.org/internet-drafts/draft-bharatia-mobileip-v4-dns-ext-0
0.txt>  and
http://search.ietf.org/internet-drafts/draft-bharatia-mobileip-v6-dns-ext-00
.txt
<http://search.ietf.org/internet-drafts/draft-bharatia-mobileip-v6-dns-ext-0
0.txt> 
 
These drafts define MIP RRP extensions to support transfer of DNS addresses
assigned by HA to the MN. This work is resulted from the original
requirements in 3GPP2 where DNS addresses are currently transferred to MN
using IPCP, which is basically a link layer specific solution. The attached
emails determine previous Mobile IP mailing list discussion where the need
of doing this work in separate (other than RFC3220) draft was identified.
 
The mechanism we have offered in these two drafts is link layer independent
solution.
 
Your comments on these drafts are appreciated.
 
Thanks,
Jayshree

-----Original Message-----
From: Charlie Perkins [mailto:[email-masked]]
Sent: Thursday, October 04, 2001 8:02 PM
To: Chowdhury, Kuntal [RICH2:2H18:EXCH]
Subject: Re: MIP extensions to support DNS

Hello Kuntal, 

I do not think this is possible.  I think it would be quite possible 
to make a separate draft for this extension, though.  And, it seems 
to me to more appropriate anyway than trying to add it to RFC2002bis, 
since the latter document wasn't supposed to have new features 
(despite appearances to the contrary). 

Regards, 
Charlie P. 

Kuntal Chowdhury wrote: 

Charlie, 
I was wondering if we still have time to add MIP extensions in 2002bis so
that DNS server addresses can be returned by the home network? We discussed
this issue in 3GPP2 and there was a requirement for this feature. Currently
DNS server addresses are negotiated by MN with PDSN/FA during IPCP phase
(RFC 1877), however there is no way to assign these DNS servers in the home
network. It would be nice if HA has option to send these DNS addresses in
the RRP message. 

I can help in writing up the text for this, if you think it's still possible
to add this feature in the draft. 

Please let me know. 

Thanks and best regards, 
Kuntal

---

From: Brian Haley <[email-masked]>
Date: Thu, 07 Mar 2002 01:13:22 -0500

"Jayshree Bharatia" wrote:
> We have recently submitted two new drafts,  >http://search.ietf.org/internet-drafts/draft-bharatia-mobileip-v4-dns-ext-00.txt and
> http://search.ietf.org/internet-drafts/draft-bharatia-mobileip-v6-dns-ext-00.txt

Hi Jayshree,

Thanks for writing this up, I have a couple of comments on the v6 draft.

> 1.1  Glossary of Terms 
>    FA          Foreign Agent

You can remove FA from the v6 draft.

> Step 2: The MN sends a Binding Update message to the HA. It is 
>           recommended that the MN should set `A' bit in the Binding 
>           Update message requesting the Binding Acknowledgement from 
>           the HA.

Don't know if it matters, but the HA must always return an Ack to the
MN,
regardless of the A bit (section 9.1, page 69 of mipv6 draft 15).

> The Mobile IP Sub-Optionsfor primary and secondary DNS servers shall 
>    have the following format

I think this sub-option requires alignment, like the HAO or alt-COA in
mipv6:

0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
                                   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                                   |  Option Type  | Option Length |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |                                                               |
   +                          DNS Address                          +
   |                                                               |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Don't know if the v4 one has the same requirement.

And just another comment.  Would it be useful to have this a variable
number
of addresses instead of fixed at two?  The length would tell you how
many
there were, similar to the ICMP Home Agent Address Discovery Reply
Message
in section 5.8 of mipv6.

-Brian