[core] Question reg. draft-fossati-tls-iot-optimizations-00

["Hudalla Kai (INST/ESY1)" <[e-mail]>]

Hi list,

I have attended last week's meeting of the T2T RG in Ludwigsburg where we had a
vivid discussion around the problems of DTLS on mobile and other NATed networks
where the device's IP address and/or port are expected to change once in a while.

We quickly came to the conclusion that the CoAP spec will need to be changed in a
way that removes the transport's addressing information from the Request/Response
matching criteria when using DTLS.

However, what alternative mechanism could be used instead?

Section 4.2 of draft-fossati-tls-iot-optimizations-00 proposes to use a
connection ID as part of the DTLS record structure. While I understand the
usefulness of using a "long term identifier" for associating the session with the
client, I do not really understand, how a "hash chain" could be put to use in
this context to provide an improved level of privacy.

Could someone (of the authors) comment on that?
 
-- 
Mit freundlichen Grüßen / Best regards

Kai Hudalla
Chief Software Architect

Bosch Software Innovations GmbH
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