Subject: [Mip4] RE: "Mobile IPv4 Dynamic Home Agent Assignment " Possibility of M N registering with multiple HAs!!

From: "Ahmad Muhanna" <[email-masked]>
Date: Fri, 24 Jun 2005 09:53:41 -0400

Hello Milind, Alpesh, Kent,

Do you have any comments regarding this?
What do you think? Is this a real issue? No issue?
Thanks for your comments!

Regards,
Ahmad

-----Original Message-----
From: Muhanna, Ahmad [RICH2:2Q30:EXCH] 
Sent: Wednesday, June 22, 2005 1:49 AM
To: [email-masked]'
Cc: [email-masked]'; [email-masked]'; [email-masked]'; Muhanna,
Ahmad [RICH2:2Q30:EXCH]
Subject: "Mobile IPv4 Dynamic Home Agent Assignment " Possibility of MN
registering with multiple HAs!!

Hello all,

My apologies in advance if this issue has been discussed before. If that is
true, can someone let me know of the conclusion. Thanks!

As per section 5.3.1 Assigned Home Agent Considerations, I find the
following paragraph: " As per the messaging proposed here, the mobile node
(or the foreign agent) sends the Registration Request to the Requested HA
address, which is a unicast address. Therefore, this document does not
specify any new behavior for the case where the HA receives a subnet
directed broadcast Registration Request as specified in section 3.8.2.1 of
the Mobile IPv4 specification [1]. Although the Home Agent field in the
Registration Request is not a unicast address, the destination IP address is
a unicast address. This avoids the problem associated with subnet-directed
broadcast destination IP address that may result in multiple HAs responding.
Thus, there is no need to deny the registration as stated in Mobile IPv4 [1]
section 3.8.3.2."

My question here is how by setting the destination IP address of the IP
packet to the HA unicast IP address guarantee that MN will avoid the
possibility of being registered with multiple HAs?

What I have in mind here, is the possibility of someone listening on that
link and all what is needed is to include the RRQ in an IP packet with the
destination IP address is set to a different HA. In other words, any HA
receives this RRQ can process this RRQ and send a confirmation reply to the
MN and MN ends up registering with multiple HAs.?

Am I correct here?
Thanks for your comments and reply.

Regards,
Ahmad

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