Re: [Ntp] Antw: Re: Antw: Re: New rev of the NTP port randomization I-D (Fwd: New Version Notification for draft-gont-ntp-port-randomization-01.txt)

Hal Murray <hmurray@megapathdsl.net> Wed, 29 May 2019 10:23 UTC

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To: "Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de>
cc: "ntp@ietf.org" <ntp@ietf.org>, hmurray@megapathdsl.net
From: Hal Murray <hmurray@megapathdsl.net>
In-Reply-To: Message from "Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de> of "Wed, 29 May 2019 11:39:16 +0200." <5CEE5344020000A1000317F9@gwsmtp.uni-regensburg.de>
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Date: Wed, 29 May 2019 03:23:25 -0700
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Subject: Re: [Ntp] Antw: Re: Antw: Re: New rev of the NTP port randomization I-D (Fwd: New Version Notification for draft-gont-ntp-port-randomization-01.txt)
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Ulrich.Windl@rz.uni-regensburg.de said:
> I agree, but please don't treat it as 64-bit random value that is to be
> guessed. 

It looks like 64 bits to me.  You don't need to put an actual time in that 
slot.  Save the time, get a random number.  Put it in the packet and save it 
too.  When a reply arrives, compare the "time stamp" in the packet with the 
saved random number.  If they match, process using the saved time.

There was a draft describing that a year or so ago.


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