RFC 197 (rfc197) - Page 2 of 5

Initial Connection Protocol - Reviewed

a similar, simple mechanism is desirable for the ICP.
Furthermore, the ICP should allow for simplex as well as
duplex connections from user to server.

     The following commands are necessary for simplex
connections:

     ISC - Initiate Simplex Connection

     ASC - Accept Simplex Connection

     RSC - Refuse Simplex Connection

     The notation for parameters is similar to that
of RFC #165:

     L - Server socket name, in one special case the
         server is "logger".

     U - User socket.

     S - Socket assigned by server for the connection
         with user.

     X - Is the byte size if U is odd and is the link
         number if U is even.

     -                           -
     X - Is the complement of X (X is the link number
         if U is odd and byte size if U is even.

     To initiate a simplex connection the user's NCP
issues:
           ISC, L, U, X

     To refuse this connection the server's NCP issues:

           RSC, L, U