Re: [TLS] WGLC for draft-ietf-tls-dtls-connection-id

Nikos Mavrogiannopoulos <> Tue, 20 November 2018 15:29 UTC

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From: Nikos Mavrogiannopoulos <>
To: Joseph Salowey <>, "<>" <>
Date: Tue, 20 Nov 2018 16:29:27 +0100
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Subject: Re: [TLS] WGLC for draft-ietf-tls-dtls-connection-id
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On Wed, 2018-11-07 at 14:39 +0700, Joseph Salowey wrote:
> This is the working group last call for the "Connection Identifiers
> for DTLS 1.2" draft available at 
> Please review the document and send your comments to the list by 2359
> UTC on 30 November 2018.


It is a very good document, I support its publication. Some editorial comments follow.

I think the paragraph of the section 3 that starts:
"This is effectively the simplest possible design that will work."

looks like unnecessary; why would previous designs be mentioned unless
there is a challenge for this protocol and in that case an appendix
may be more suitable. What about replacing with:
"The design is kept simple to ease implementation and deployment"

In security considerations the following two paragraphs seem to be part
of a single one, that is separated by a However? (i.e., replace Importantly with However),
or do I missread it?

   With multi-homing, an adversary is able to correlate the
   communication interaction over the two paths, which adds further
   privacy concerns.

   Importantly, the sequence number makes it possible for a passive
   attacker to correlate packets across CID changes.  Thus, even if a
   client/server pair do a rehandshake to change CID, that does not
   provide much privacy benefit.