Network Working Group                                          J. Postel
Request for Comments: 145                                     UCLA - NMC
NIC: 6739                                                     4 May 1971
Updates: 123
Obsoletes: 127

              Initial Connection Protocol Control Commands

     The following is my interpretation of the exchange between NCP's
   which would be necessary to carry out the Initial Connection Protocol
   of RFC #123.  (This note corrects an error pointed out by Eric
   Harslem of RAND).

      Server NCP                      User NCP
      __________                      ________

      Listen for Connection L         RTS, U, L, l
                                                  A

      STR, L, U, 32                   ALL, l  , 1, 32
                                            A

      Send 32 bits of data
      in 1 message on link l
                            A

      (value is S)                    Receive 32 bits of data
                                      from link l  (value is S)
                                                 A

      CLS, L, U                       CLS, U, L

      STR, S+1, U+1, B                STR, U+1, S, B
                      s                             u

      RTS, S, U+1, l                  RTS, U, S+1, l
                    B                               C

      wait for connection             wait for connection
      ALL, l , m , b                  ALL, l , m , b
            B   B   B                       C   C   C

      data sent to link l             data sent on link l
                         C                               B

      data received on link           data received on link l
                           B                                 C




Postel                                                          [Page 1]

RFC 145               Initial Connection Protocol             4 May 1971


      l , l , and l , are links, m  and m  are messages allocations, b
       A   B       C              B      C                            B
      and b  are bit allocations, and all other symbols are defined in
           C
      RFC #123.

      [This RFC is also available in .PS and. PDF format.]

          [ This RFC was put into machine readable form for entry ]
               [ into the online RFC archives by Lorrie Shiota]









































Postel                                                          [Page 2]