Network Working Group                                          J. Postel
Request for Comments: 867                                            ISI
                                                               May 1983



                           Daytime Protocol




This RFC specifies a standard for the ARPA Internet community.  Hosts on
the ARPA Internet that choose to implement a Daytime Protocol are
expected to adopt and implement this standard.

A useful debugging and measurement tool is a daytime service.  A daytime
service simply sends a the current date and time as a character string
without regard to the input.

TCP Based Daytime Service

  One daytime service is defined as a connection based application on
  TCP.  A server listens for TCP connections on TCP port 13.  Once a
  connection is established the current date and time is sent out the
  connection as a ascii character string (and any data received is
  thrown away).  The service closes the connection after sending the
  quote.

UDP Based Daytime Service

  Another daytime service service is defined as a datagram based
  application on UDP.  A server listens for UDP datagrams on UDP port
  13.  When a datagram is received, an answering datagram is sent
  containing the current date and time as a ASCII character string (the
  data in the received datagram is ignored).

Daytime Syntax

  There is no specific syntax for the daytime.  It is recommended that
  it be limited to the ASCII printing characters, space, carriage
  return, and line feed.  The daytime should be just one line.

     One popular syntax is:

        Weekday, Month Day, Year Time-Zone

        Example:

           Tuesday, February 22, 1982 17:37:43-PST





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RFC 867                                                         May 1983
Daytime Protocol


     Another popular syntax is that used in SMTP:

        dd mmm yy hh:mm:ss zzz

        Example:

           02 FEB 82 07:59:01 PST

NOTE:  For machine useful time use the Time Protocol (RFC-868).









































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