More ntp fun: I now have multicast ntp time working and documented. With the listed ntp key clients can use the multicasted network time from ntp.cs.uu.nl. The outgoing timestamps look like this in tcpdump:14:45:06.821419 IP (tos 0x0, ttl 30, id 6195, offset 0, flags [none], proto 17, length: 96) 131.211.84.189.ntp > 224.0.1.1.ntp: NTPv4, length 68 Broadcast, Leap indicator: (0), Stratum 2, poll 6s, precision -19 Root Delay: 0.000000, Root dispersion: 0.001724, Reference-ID: 127.127.22.0 Reference Timestamp: 3424077852.817587474 (2008/07/03 14:44:12) Originator Timestamp: 0.000000000 Receive Timestamp: 0.000000000 Transmit Timestamp: 3424077906.819248263 (2008/07/03 14:45:06) Originator - Receive Timestamp: 0.000000000 Originator - Transmit Timestamp: 3424077906.819248263 (2008/07/03 14:45:06)I also see multicasted time from 192.36.143.151 (time2.stupi.se) but I can't find a key for it.