TIME protocol
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The TIME service is an Internet protocol defined in RFC 868. Its purpose is to provide a site-independent, machine readable date and time.
TIME can operate over either TCP or UDP. When operating over TCP, a host connects to a server that supports the TIME protocol on TCP port 37. The server then sends the time as a 32-bit binary number in network byte order representing a number of seconds since 00:00 (midnight) 1 January, 1900 GMT. The host receives the time and closes the connection.
When operating over UDP, the client sends a (typically empty) datagram to UDP port 37. The server responds with a single datagram of length 4 containing the time. There is no connection setup or teardown.
In modern practice, the TIME protocol is completely superseded by the Network Time Protocol (NTP).
[edit] inetd implementation of TIME
On Linux, FreeBSD, and other UNIX-like operating systems a time server is built into the inetd daemon. The time service is usually not enabled by default. It may be enabled by adding the following lines to the file /etc/inetd.conf and telling inetd to reload its configuration:
time stream tcp nowait root internal time dgram udp wait root internal
