[babel] Paul Wouters' Discuss on draft-ietf-babel-rtt-extension-05: (with DISCUSS and COMMENT)

[Paul Wouters via Datatracker <[e-mail]>]

Paul Wouters has entered the following ballot position for
draft-ietf-babel-rtt-extension-05: Discuss

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DISCUSS:
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Thanks to Shivan Sahib for the SecDir review.

I agree with Shivan's concern about privacy here. Perhaps something more can be
said in the document? Maybe a Privacy Considerations section? Should a client
using a VPN add some random range delay for privacy? Should it just say/act
with something very slow to "opt out" of this entirely so the only information
leaked is "not local"? eg cause it to be like 1000ms ? Is there another way to
opt-out? Eg by refusing to answer as per this draft that could be recommended ?

I'm also worried about malicious clients sending pre-emptive IHUs and lying
about the RTT, and thus making themselves the preferred gateway. This could be
avoided by adding a random COOKIE in the RTT timer request. Is there a reason
why not to take this extra security step? (I'm not a Babel expert, so it is
possible my envisioned scenario is not possible)


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COMMENT:
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nit: expand IHU on first use (maybe with exact reference)