Subject: [MOBILE-IP] Registration Reply

From: Meeta Sharma <[email-masked]>
Date: Mon, 9 Oct 2000 16:08:15 -0700

Hi all,
I was looking into mobile ip(rfc 2002) for one of my projects. I had a
question:
What happens when the registration reply(i) from foreign agent to mobile
node is delayed? It can happen that the timer at the mobile node expires
and that the mobile node sends another request(i+1)..but then it gets a
reply(i) would it accept it or reject it?

Also, what if Foreign agent sees that it had sent a reply for (i) and now
is getting a request(i+1) then would it discard it or send the reply back
again? without going to the home agent?

I am a little confused and maybe the answers would help me in my model.
Thanks,
Regards,
Meeta

---

From: "Gowri S.Makineni" <[email-masked]>
Date: Tue, 10 Oct 2000 09:07:25 -0500

>reply(i) would it accept it or reject it?

If the timer expires at the mobile node, it sends another registration
request,
and discards replies to the previous requests that it sent.

>again? without going to the home agent?

The foreign agent forwards all "proper" requests that it receives and forwards
them to the respective agents. Your (i+1) request is also forwarded to your
HA.
The replies of i and i+1 requests from the HA would be sent to the mobile
node provided time out does not occur at the FA.

>I am a little confused and maybe the answers would help me in my model.
Hope that helps.
GSM
Gowri S. Makineni
Sr. Systems Engineer,
Ecutel
(703)354-4140 X-110
----------------------------------------------------------

---

From: Meeta Sharma <[email-masked]>
Date: Wed, 11 Oct 2000 10:46:10 -0700

hi,
thanks for this reply..
i have another question..
The HA agent might only have the option of supporting one binding..and
then if it gets a req(i+1)..and it has already granted req(i) for the same
binding then would it reject(i+1)?
also, then if it rejects then the tunnel would not be complete..?
I am wrong somewhere in my conclusion?
Thanks,
Regards,
-Meeta

---

From: "Gowri S.Makineni" <[email-masked]>
Date: Wed, 11 Oct 2000 14:39:58 -0500

>I am wrong somewhere in my conclusion?

The registration gets updated, since the shuttle uses the same care of address
of the FA. The HA does not distinguish between the request of i+1 or i+10.
If you want multiple bindings the shuttle should specify that it
needs bindings and turn the 'S' bit flag ON in the registration request or
else
the information at the HA is just updated for that shuttle.

By the definition of bindings means that the shuttle has multiple care of
addresses and it is registering all those addresses with the HA.

-GSM

>-Meeta

Gowri Shankar Makineni
Sr. Systems Engineer,
Ecutel
(703)354-4140 X-110