RFC 44 (rfc44) - Page 1 of 3

Comments on NWG/RFC 33 and 36

Network Working Group                                        A. Shoshani
Request for Comments: 44                                         R. Long
                                                            A. Landsberg
                                          System Development Corporation
                                                           10 April 1970


                     Comments on NWG/RFC 33 and 36

   Generally, we are satisfied with the suggestions for the new Host-
   to-Host protocol.  However, we think that a few refinements may be
   helpful.

   I.   It seems that there are two cases of reconnection:

     1. Reconnect from a socket in a local Host to another socket in the
        local Host.  This was referred to in RFC #33 as "switch".  The
        local sockets can belong to different processes (such as the
        "Login" process switching a connection to another process just
        created) or can belong to the same process (such as a process
        that accepts calls for connections on a particular socket, and
        after a connection is established switches to another of his
        sockets).

     2. Reconnect from a socket at a local Host to a socket in a foreign
        Host.

     We suggest separation of these two cases for the following reasons:
     a) Reconnection in Case 1 is necessary and useful, while the
        usefulness of Case 2 is still in doubt.

     b) Case 1 is simple to implement (at least conceptually) while Case
        2 involves an elaborate mechanism of commands because of the
        asynchronous nature of the network (four out of nine commands
        were suggested to handle Case 2 in RFC #36).

     Thus we think that at least in the first usage of the Host-to-Host
     protocol reconnection in Case 2 should be left out.  An additional
     system call (not a command) is therefore needed to permit Case 1,
     which is SWITCH .

   II.  The CLOSE command as suggested in RFC #36 seems to be used for
        two purposes: block a connection and abort a connection.  To
        avoid ambiguity it would be desirable to have two commands:
        BLOCK and CLOSE.  As suggested in RFC #36, the response for both
        commands can be the SUSPEND command which acknowledges the
        reception of BLOCK or CLOSE commands.




Shoshani, et al.