RFC 333 (rfc333) - Page 1 of 26


Proposed experiment with a Message Switching Protocol



Alternative Format: Original Text Document



Network Working Group                                       Bob Bressler
Request for Comments: 333                           MIT/Dynamic Modeling
NIC # 9926                                                    Dan Murphy
Category: C9 (experimentation)                                 BBN/TENEX
Obsoletes: 62                                                Dave Walden
Updates: none                                                    BBN/IMP
                                                             15 May 1972


        A PROPOSED EXPERIMENT WITH A MESSAGE SWITCHING PROTOCOL


CONTENTS

   Introduction ..................................................  1
   Some Background ...............................................  2
   References ....................................................  3
   MSP Specification .............................................  4
   Issue .........................................................  8
   Message Header ................................................ 10
   Examples ...................................................... 15
   TELNET ........................................................ 16
   The Information Operator ...................................... 16
   Unique Port Numbers ........................................... 20
   Flow Chart .................................................... 23
   MSP Variations ................................................ 25
   Appendix ...................................................... 26

INTRODUCTION

   A message switching protocol (MSP) is a system whose function is to
   switch messages among its ports.

   For example, there is an implementation of an MSP in each Interface
   Message Processor.  We believe that the effective utilization of
   communications networks by computer operating systems will require a
   better understanding of MSPs.  In particular, we feel that Network
   Control Programs (NCPs), as they have been implemented on the ARPA
   Computer Network (ARPANET), do not adequately emphasize the
   communications aspects of networking -- i.e., they reflect a certain
   reluctance on the part of systems people to move away from what we
   term "the stream orientation".  We propose, as an aside the network
   development using the current NCPs, to rethink the design of NCP-
   level software beginning with a consideration of MSPs.

   The thrust of this note is to sketch how one would organize the
   lowest level host-host protocol in the ARPANET around MSPs and how
   this organization would affect the implementation of host software.



Bressler, et al.            Experimentation