Subject: [MOBILE-IP] A comment on Minimal Latency Secure Hand-off

From: Tapio Suihko <[email-masked]>
Date: Fri, 17 Mar 2000 16:40:59 +0200

Hi All,

The "Minimal Latency Secure Hand-off" draft specifies a mechanism for
letting an MN convey keying information between FAs. This information
is embedded in an MN-Key-Token Extension, which is a subtype of
Generalized MN-FA Key Reply Extension.

There might be situations, where the MN could communicate to an FA, in
addition to registration keys, other state information from a previous
FA (related to QoS, authorization, or path setup, for
example). Therefore, I think that defining a Generalized Opaque
extension might be useful. The semantics would be trivial: the MN
should just pass any blobs to an FA if the advertised FA-NAI implies
that the MN is migrating within the same administrative domain, or
optionally a lifetime could be attached to the blob, so that the MN
can discard it when the lifetime expires.

Such generic blobs with simple semantics might facilitate developing
intra-domain protocols and policies which, however, could be
transparent to MNs and would allow interoperability with any MN.

Anyway, according to the "Minimal Latency Secure Hand-off" draft, the
Key Reply extensions may be passed to the MN without the MN having
requested this data and, on the other hand, it may sound slightly
awkward that an MN should send a Key Reply extension to an FA (and
only do this depending on the specific subtype of the
extension). Therefore, one might wonder whether Key Reply really is
the most appropriate extension to apply in this case.

Regards,
Tapio

--
Tapio Suihko            Technical Research Centre of Finland (VTT/IT)