Symmetricom Time Server - Manual (Page 119)

6000-100AppC.fm Rev. D TimeVault™ User’s Manual C-105
C
TIME and DAYTIME Protocols
C.1 TIME Protocol as per RFC-868
TIME protocol provides a site-independent, machine readable date and time. The TIME
service sends back to the originating source the UTC time in seconds since midnight on
January 1, 1900.
This protocol may be used either above the Transmission Control Protocol (TCP) or above
the User Datagram Protocol (UDP).
When used via UDP, the TIME service works as follows:
Server:Listen on port 37 (45 octal).
Client:Send an empty datagram to port 37.
Server:Send a datagram containing the UTC time as a 32 bit binary number.
Client:Receive the TIME datagram.
The server listens for a datagram on port 37. When a datagram arrives, the server returns
a datagram containing the 32-bit time value. If the server is unable to determine the time
at its site, it should discard the arriving datagram and make no reply.
C.1.1 The Time Protocol Format
The time is the number of seconds since 00:00 (midnight) 1 January 1900 UTC, such that
the time 1 is 12:00:01 AM on January 1, 1900 UTC; this base will serve until the year
2036.