[ntp:questions] Version Field in Reply Packets

David Woolley david at djwhome.demon.co.uk
Tue Jan 23 21:42:50 UTC 2007

In article <1169555391.897031.218530 at h3g2000cwc.googlegroups.com>,
Md Nazeem <charan.madhu at gmail.com> wrote:

> We are having time server running NTPV3 (Server mode), and a client
> running NTPV4.
> What should be version field in the packet replied from the server ?

I seem to remember that the reference implementation of version 3 will
reject up version polls, although it looks as though version 4.2.0
accepts them, although it rejects up version mode 7 management requests.
It would generally be advisable to explicitly specify that version 3
should be used in the server lines for the downversion servers.

Obviously it cannot respond with a version higher than 3, because it 
doesn't know the future.

NTP V3 is obsolete, though.

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