ntp.conf changes for NTS

[Achim Gratz]

Gary E. Miller via devel writes:
>> Optionally, yes.  I think this part of the RFC is poorly thought out,
>> I'd prefer if the NTS-KE just straight failed if the server you
>> specified is not available.
>
> I'm not sure why it has to be in the NTS-KE server.  The client is free
> to accept or reject the offered NTPD server.

Well, yes.  But I'd rather fail if my request can not be fulfilled than
getting something else I didn't ask for and then trying to figure out
what to do with what I've got that I didn't want.  That's a design
decision to make.  Each of the times you can go two different routes
you'll double the amount of tests yoou'll have to look at.

>> Which is however an option the
>> implementer of the NTS-KE could chose.
>
> Nut the NTS-KE does not care, so it has no basis to choose.

You can't read.  The option for whoever implements the NTS-KE is to
either return failure or return some other server that was not
requested.  My preference is that the ntpsec decides to return failure.
As long as the RFC is what it is, the client needs to deal with a
non-fail return anyway, so it'll have to carry that baggage.

> So, back to how we update ntp.conf to encode "ask" and "require".
>
> I think the current proposal works:
>
> nts nts-ke.example.com
> nts nts-ke.example.com ask ntp.example.com
> nts nts-ke.example.com require ntp.example.com
>
> Maybe expanded to ask for 3 pool servers:
>
> nts nts-ke.example.com pool 3

The client must know which servers it got from a pool, so it can
re-mobilize another server from the pool if needed.  The number of pool
servers to request is currently determined by ntpd based on some
variables related to the number of clocks to use.  I don't see a good
reason (yet) to switch to an explicit number, especially since the
client will prune the clock list later on anyway.  So I'd use "pool"
like a flag in the nts config.


Regards,
Achim.
-- 
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

Factory and User Sound Singles for Waldorf rackAttack:
http://Synth.Stromeko.net/Downloads.html#WaldorfSounds