JDS Uniphase RS-232 operation manual Appendix H Internet Time Synchronization

Appendix H – Internet Time Synchronization

The Web Xpander can be configured to automatically synchronize your STARGATE's internal clock daily via the internet to maintain an accurate time setting.

There are several different protocols commonly used for internet time syncing including DAYTIME, TIME, and NTP. See http://www.boulder.nist.gov/timefreq/service/its.htm for a more detailed description of the different protocols.

The Web Xpander uses the "DAYTIME" Protocol (RFC-867) over TCP port 13. A time server that supports this protocol via TCP on port 13 should work with the Web Xpander. A list of compatible time servers can be found at: http://www.boulder.nist.gov/timefreq/service/time-servers.html

The Web Xpander will attempt to connect to the specified time server at or just after the time specified on the “Settings” page. Connections are always made on the half hour (i.e. 3:30am). If the minute portion of the time received from the time server is between 15 and 45 (i.e. 3:15am – 3:45am) the Web Xpander will set both its own internal clock and the STARGATE clock to this adjusted value. To account for different time zones, only the minute portion of the time is examined and updated.

The “Settings” page of the Web Xpander shows the date and time of the last successful time update.