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UDP/123 policers & status

I found this as an unsent draft - I hope I didn't send it before.

On 3/30/2020 2:01 AM, Ragnar Sundblad wrote:
>> On 30 Mar 2020, at 08:18, Saku Ytti <saku at ytti.fi> wrote:
>> On Mon, 30 Mar 2020 at 01:58, Ragnar Sundblad <ragge at kth.se> wrote:
>>> A protocol with varying packet size, as the NTS protected NTP is,
>>> can easily have the bad property of having responses larger than the
>>> requests if not taken care. Donâ??t you see that?
>> Why? Why not pad requests to guarantee attenuation vector until
>> authenticity of packets can be verified?
> Right, and NTS does that.

There is more to NTP than NTS.

Are y'all seriously recommending that NTP always sends a max-sized
packet as a client request so the client/server can send back an
identical response?  That's just wasting huge amounts of bandwidth to
save the possibility of a possibly larger response.

And just becase a responbse may be larger, that doesn't necessarily
translate into an amplification vector.

The alternative seems to be that the client sends a smaller request and
is ready when the response from the server is "Send your request again,
but this time pad it to NNN bytes so I can respond with the same sized

> Ragnar

Harlan Stenn <stenn at nwtime.org>
http://networktimefoundation.org - be a member!