Re: [Homenet-babel-sec] [babel] What's up with HNCP security?

Juliusz Chroboczek <jch@irif.fr> Mon, 29 May 2017 14:02 UTC

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Date: Mon, 29 May 2017 16:02:37 +0200
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From: Juliusz Chroboczek <jch@irif.fr>
To: Ted Lemon <mellon@fugue.com>
Cc: Markus Stenberg <markus.stenberg@iki.fi>, homenet-babel-sec@ietf.org, babel@ietf.org
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Subject: Re: [Homenet-babel-sec] [babel] What's up with HNCP security?
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> In the case we are talking about, a shared key doesn't work because if any
> device on the network is pwned, it can masquerade as any other device to
> escape detection. You or I could do a fault isolation process to figure out
> which device has been pwned, but we can't expect homenet users to be able to
> do that.

I think we're all well aware of the advantages of per-device keys.  I think
we're also well aware that there are tradeoffs between functionality and
complexity, and that sometimes it is worth giving up on features in order
to keep complexity at a manageable level.  (Radius, sheesh.)

I think we'd need a prototype in order to make an informed judgement.

-- Juliusz