[ntpwg] Issues with the NTP draft -06

[Heiko Gerstung]

Brian Utterback schrieb:
> One of the key pieces you need to remember is that the while the refid
> should be unique, unless the data you want to use for the server's
> refid is already in the data somewhere that arrives from the server,
> the refid must be derivable from the client.
>
> To answer Heiko's comment about the stratum level, the problem with
> stratum level is the propagation delay when the level changes. However,
> the reason having only two levels of loop detection works is that the
> stratum level generally works for larger loops.
Well, is the propagation delay of the refid better? As far as I can tell 
the stratum level and the refid are changing at exactly the same time or 
do I miss something?
> I have always wondered if there might not be a way to get better
> loop detection if you treated the refid as a sort of shift register.
> Each server would choose a random one byte number at shift that number
> on the the refid it passes to the client. Then the client would look
> at each byte of the refid from all of its servers. If the higher order
> byte matches the clients random byte, avoid it if you can. If the
> top two bytes match the lowest byte of the client's server's refid and
> the the client's own byte, reject it. Reject if more bytes match.
I think that the stratum level offers the same functionality with a 
simpler approach. Add 1 to the stratum level of your upstream server and 
never synchronize with a server that has the same or higher stratum 
level. What a ruleset :-)

Cheers,
Heiko