[dtn-interest] On dependence of security on synchronized clocks

<l.wood@surrey.ac.uk> Mon, 18 August 2014 12:49 UTC

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From: l.wood@surrey.ac.uk
To: dtn-interest@irtf.org
Thread-Topic: On dependence of security on synchronized clocks
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Date: Mon, 18 Aug 2014 12:49:15 +0000
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Subject: [dtn-interest] On dependence of security on synchronized clocks
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(well, this list seems dead.)

http://engineering.bergcloud.com/2014/08/problem-with-ntp/

has a nice practical example of how security starts to break without synchronised clocks.

Insist on the need for security, and you will insist on the need for synchronised clocks. Which is, I think, where DTN came in.

(The problem's a litte contrived, in that you should be getting time from someone you trust - private tunnel - or someone your ISP views as authoritative, which is its timeserver. Timeserving across the internet is often messier than the hierarchy one might expect. But still, nice example.)


Lloyd Wood
http://sat-net.com/L.Wood/dtn