G.1.1.4 Basic Course of Events.

The DHCP server may have provided a list of NTP servers or one may be obtained through optional NTP discovery mechanisms. If this list is empty and no manually configured NTP server address is present, the client shall select its internal clock as the time source (see below). If the list is not empty, the client shall attempt to maintain time synchronization with all those NTP servers. The client may attempt to use the multi-cast, manycast, and broadcast options as defined in RFC-1305. It shall utilize the point to point synchronization option if these are not available. The synchronization shall be in compliance with either RFC-1305 (NTP) or RFC-2030 (SNTP).

If the application requires time synchronization of better than 1s mean error, the client should use NTP. SNTP cannot ensure a more accurate time synchronization.

The DHCP server may have provided a UTC offset between the local time at the machine and UTC. If this is missing, the UTC offset will be obtained in a device specific manner (e.g. service, CMOS). If the UTC offset is provided, the client shall use this offset for converting between UTC and local time.