Re: [Ntp] A simpler way to secure PTP

Daniel Franke <> Wed, 12 May 2021 05:44 UTC

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From: Daniel Franke <>
Date: Wed, 12 May 2021 01:44:00 -0400
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To: Heiko Gerstung <>
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Subject: Re: [Ntp] A simpler way to secure PTP
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On Wed, May 12, 2021, 01:14 Heiko Gerstung <>

> that’s why we use the integrated security mechanism for unicast PTP and
> just use the NTS-KE protocol to exchange the required keys for that. Due to
> the fact that the two protocols NTP and PTP work in a completely different
> way, there is not more that can be reused. I agree we could find another
> way to exchange keys and it doesn’t have to be NTS. But why not using it,
> now that it is there?
Return-routability checking (what I referred to in my previous message as
SYN-cookie-like schemes but I like the terminology of
doesn't require key exchange at all. The only keys involved are held by the
server and no other party. The client just echoes back the opaque blobs
that the server sends it.