Subject: [Hipsec] Martin Duke's No Objection on draft-ietf-hip-dex-24: (with COMMENT)

From: Martin Duke via Datatracker <[email-masked]>
Date: Mon, 15 Mar 2021 21:40:32 -0700

Martin Duke has entered the following ballot position for
draft-ietf-hip-dex-24: No Objection

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COMMENT:
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Thanks for providing detailed data on why this sort of security compromise is
necessary. I am not a crypto expert, but wonder if there is some way to
leverage the potentially asymmetric capabilities of two HIP nodes to offload
more of the computation onto one of them.

- This is optional, but some suggest replacing the term "man in the middle"
with "on-path attacker". Please do it if you are amenable.

- Does HIP DEX always put version 2 in the version field, or is DEX somehow
orthogonal to HIP version?

- Thanks for the discussion of the I2 retransmission timeout in Sec 9. It
addressed my concerns in reading Section 4. The "reported delay + 1/2 maximum
RTT" formula seems like an odd heuristic for what ought to be "the reported
delay plus a little more", but it *does* limit a spoofed NOTIFY to no more than
doubling the retransmission rate.