SMUX DEFINITIONS ::= BEGIN

   IMPORTS
           DisplayString, ObjectName
                   FROM RFC1155-SMI

           PDUs
                   FROM RFC1157-SNMP;


   -- tags for SMUX-specific PDUs are application-wide to
   -- avoid conflict with tags for current (and future)
   -- SNMP-generic PDUs

   SMUX-PDUs ::=
       CHOICE {
           open            -- SMUX peer uses
               OpenPDU,    -- immediately after TCP open

           close           -- either uses immediately before TCP close
               ClosePDU,

           registerRequest -- SMUX peer uses
               RReqPDU,

           registerResponse -- SNMP agent uses
               RRspPDU,

               PDUs,       -- note that roles are reversed:
                           --   SNMP agent does get/get-next/set
                           --   SMUX peer does get-response/trap

           commitOrRollback -- SNMP agent uses
               SOutPDU
      }


   -- open PDU
   -- currently only simple authentication

   OpenPDU ::=
       CHOICE {
          simple





              SimpleOpen
       }

   SimpleOpen ::=
       [APPLICATION 0] IMPLICIT
           SEQUENCE {
               version     -- of SMUX protocol
                   INTEGER {
                       version-1(0)
                   },

               identity    -- of SMUX peer, authoritative
                   OBJECT IDENTIFIER,

               description -- of SMUX peer, implementation-specific
                   DisplayString,

               password    -- zero length indicates no authentication
                   OCTET STRING
           }


   -- close PDU

   ClosePDU ::=
       [APPLICATION 1] IMPLICIT
           INTEGER {
               goingDown(0),
               unsupportedVersion(1),
               packetFormat(2),
               protocolError(3),
               internalError(4),
               authenticationFailure(5)
           }


   -- insert PDU

   RReqPDU ::=
       [APPLICATION 2] IMPLICIT
           SEQUENCE {
               subtree
                   ObjectName,

               priority    -- the lower the better, "-1" means default
                   INTEGER (-1..2147483647),

               operation





                   INTEGER {
                       delete(0),    -- remove registration
                       readOnly(1),  -- add registration, objects are RO
                       readWrite(2)  --   .., objects are RW
                   }
           }

   RRspPDU ::=
       [APPLICATION 3] IMPLICIT
           INTEGER {
               failure(-1)

              -- on success the non-negative priority is returned
           }

   SOutPDU ::=
       [APPLICATION 4] IMPLICIT
           INTEGER {
               commit(0),
               rollback(1)
           }

   END