Subject: [mobile-ip] Generalized MN-HA and MN-FAKey Reply Extension

From: Joe Lau <[email-masked]>
Date: Sun, 29 Jul 2001 12:40:18 -0700 (PDT)

Hello Charlie and Pat,

On your latest draft <draft-ietf-mobileip-gen-key-01.txt>,
I am puzzled over the asymmetry between the MN-HA Key Reply Extension
and the MN-FA Key Reply Extension.   The former has a lifetime field
but the latter does not.  I understand that the lifetime of the
MN-FA Key will come from the Unsolicited MN-FA Key Material From AAA Subtype.

But I don't understand why these two keys have to be treated differently
as far as how the lifetime is placed.

Thanks in advance for your clarification.

Regards,

Joe Lau

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From: Charlie Perkins <[email-masked]>
Date: Sun, 29 Jul 2001 23:16:45 -0700

Hello Joe,

These are generalized key extensions.  Subtypes will define more
data fields.  There is a good argument that some specific key
subtypes of the MN-FA Key Reply extension will NOT have
a lifetime, because the key will have the same lifetime as the
Mobile IP registration lifetime.  In fact, one could argue that
this would be the preferred mode of operation for the security
association between the mobile node and the foreign agent.

The security association between mobile node and home
agent is clearly different, and the lifetime of that association
would not typically be controlled by registration factors.
Since every security associatoin has to have a lifetime, and
there isn't any likely implicit lifetime, it would be present for
every subtype, and thus belongs in the generalized extension.

At least that's my understanding!

Regards,
Charlie P.

Regards,
Charlie P.

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From: Pat Calhoun <[email-masked]>
Date: Mon, 30 Jul 2001 07:07:33 -0700

Joe,

Also you will notice that the MN-FA AAA subtype does include the missing
lifetime. So, in the AAA case, both the MN-HA and the MN-FA have lifetimes.

PatC