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          Network Working Group                                  J. Case
          Request for Comments: 1449                 SNMP Research, Inc.
                                                           K. McCloghrie
                                                      Hughes LAN Systems
                                                                 M. Rose
                                            Dover Beach Consulting, Inc.
                                                           S. Waldbusser
                                              Carnegie Mellon University
                                                              April 1993


                                Transport Mappings
                               for version 2 of the
                   Simple Network Management Protocol (SNMPv2)


          Status of this Memo

          This RFC specifes an IAB standards track protocol for the
          Internet community, and requests discussion and suggestions
          for improvements.  Please refer to the current edition of the
          "IAB Official Protocol Standards" for the standardization
          state and status of this protocol.  Distribution of this memo
          is unlimited.


          Table of Contents


          1 Introduction ..........................................    2
          1.1 A Note on Terminology ...............................    2
          2 Definitions ...........................................    3
          3 SNMPv2 over UDP .......................................    7
          3.1 Serialization .......................................    7
          3.2 Well-known Values ...................................    7
          4 SNMPv2 over OSI .......................................    8
          4.1 Serialization .......................................    8
          4.2 Well-known Values ...................................    8
          5 SNMPv2 over DDP .......................................    9
          5.1 Serialization .......................................    9
          5.2 Well-known Values ...................................    9
          5.3 Discussion of AppleTalk Addressing ..................    9
          5.3.1 How to Acquire NBP names ..........................   10
          5.3.2 When to Turn NBP names into DDP addresses .........   11
          5.3.3 How to Turn NBP names into DDP addresses ..........   11
          5.3.4 What if NBP is broken .............................   12
          6 SNMPv2 over IPX .......................................   13
          6.1 Serialization .......................................   13
          6.2 Well-known Values ...................................   13
          7 Proxy to SNMPv1 .......................................   14
          7.1 Transport Domain: rfc1157Domain .....................   14
          7.2 Authentication Algorithm: rfc1157noAuth .............   14


          Case, McCloghrie, Rose & Waldbusser                   [Page i]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          8 Serialization using the Basic Encoding Rules ..........   16
          8.1 Usage Example .......................................   17
          9 Acknowledgements ......................................   18
          10 References ...........................................   22
          11 Security Considerations ..............................   24
          12 Authors' Addresses ...................................   24
          13 Security Considerations ..............................   25
          14 Authors' Addresses ...................................   25










































          Case, McCloghrie, Rose & Waldbusser                   [Page 1]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          1.  Introduction

          A network management system contains: several (potentially
          many) nodes, each with a processing entity, termed an agent,
          which has access to management instrumentation; at least one
          management station; and, a management protocol, used to convey
          management information between the agents and management
          stations.  Operations of the protocol are carried out under an
          administrative framework which defines both authentication and
          authorization policies.

          Network management stations execute management applications
          which monitor and control network elements.  Network elements
          are devices such as hosts, routers, terminal servers, etc.,
          which are monitored and controlled through access to their
          management information.

          The management protocol, version 2 of the Simple Network
          Management Protocol [1], may be used over a variety of
          protocol suites.  It is the purpose of this document to define
          how the SNMPv2 maps onto an initial set of transport domains.
          Other mappings may be defined in the future.

          Although several mappings are defined, the mapping onto UDP is
          the preferred mapping.  As such, to provide for the greatest
          level of interoperability, systems which choose to deploy
          other mappings should also provide for proxy service to the
          UDP mapping.


          1.1.  A Note on Terminology

          For the purpose of exposition, the original Internet-standard
          Network Management Framework, as described in RFCs 1155, 1157,
          and 1212, is termed the SNMP version 1 framework (SNMPv1).
          The current framework is termed the SNMP version 2 framework
          (SNMPv2).













          Case, McCloghrie, Rose & Waldbusser                   [Page 2]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          2.  Definitions

          SNMPv2-TM DEFINITIONS ::= BEGIN

          IMPORTS
              snmpDomains, snmpProxys
                  FROM SNMPv2-SMI
              TEXTUAL-CONVENTION
                  FROM SNMPv2-TC;

          -- SNMPv2 over UDP

          snmpUDPDomain  OBJECT IDENTIFIER ::= { snmpDomains 1 }
          -- for a SnmpUDPAddress of length 6:
          --
          -- octets   contents        encoding
          --  1-4     IP-address      network-byte order
          --  5-6     UDP-port        network-byte order
          --
          SnmpUDPAddress ::= TEXTUAL-CONVENTION
              DISPLAY-HINT "1d.1d.1d.1d/2d"
              STATUS       current
              DESCRIPTION
                      "Represents a UDP address."
              SYNTAX       OCTET STRING (SIZE (6))

























          Case, McCloghrie, Rose & Waldbusser                   [Page 3]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          -- SNMPv2 over OSI

          snmpCLNSDomain OBJECT IDENTIFIER ::= { snmpDomains 2 }
          snmpCONSDomain OBJECT IDENTIFIER ::= { snmpDomains 3 }
          -- for a SnmpOSIAddress of length m:
          --
          -- octets   contents            encoding
          --    1     length of NSAP      "n" as an unsigned-integer
          --                                (either 0 or from 3 to 20)
          -- 2..(n+1) NSAP                concrete binary representation
          -- (n+2)..m TSEL                string of (up to 64) octets
          --
          SnmpOSIAddress ::= TEXTUAL-CONVENTION
              DISPLAY-HINT "*1x:/1x:"
              STATUS       current
              DESCRIPTION
                      "Represents an OSI transport-address."
              SYNTAX       OCTET STRING (SIZE (1 | 4..85))
































          Case, McCloghrie, Rose & Waldbusser                   [Page 4]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          -- SNMPv2 over DDP

          snmpDDPDomain  OBJECT IDENTIFIER ::= { snmpDomains 4 }
          -- for a SnmpNBPAddress of length m:
          --
          --    octets      contents         encoding
          --       1        length of object "n" as an unsigned integer
          --     2..(n+1)   object           string of (up to 32) octets
          --      n+2       length of type   "p" as an unsigned integer
          -- (n+3)..(n+2+p) type             string of (up to 32) octets
          --     n+3+p      length of zone   "q" as an unsigned integer
          -- (n+4+p)..m     zone             string of (up to 32) octets
          --
          -- for comparison purposes, strings are case-insensitive
          --
          -- all strings may contain any octet other than 255 (hex ff)
          --
          SnmpNBPAddress ::= TEXTUAL-CONVENTION
              STATUS       current
              DESCRIPTION
                      "Represents an NBP name."
              SYNTAX       OCTET STRING (SIZE (3..99))


          -- SNMPv2 over IPX

          snmpIPXDomain  OBJECT IDENTIFIER ::= { snmpDomains 5 }
          -- for a SnmpIPXAddress of length 12:
          --
          -- octets   contents            encoding
          --  1-4     network-number      network-byte order
          --  5-10    physical-address    network-byte order
          -- 11-12    socket-number       network-byte order
          --
          SnmpIPXAddress ::= TEXTUAL-CONVENTION
              DISPLAY-HINT "4x.1x:1x:1x:1x:1x:1x.2d"
              STATUS       current
              DESCRIPTION
                      "Represents an IPX address."
              SYNTAX       OCTET STRING (SIZE (12))










          Case, McCloghrie, Rose & Waldbusser                   [Page 5]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          -- for proxy to community-based SNMPv1 (RFC 1157)

          rfc1157Proxy   OBJECT IDENTIFIER ::= { snmpProxys 1 }

          -- uses SnmpUDPAddress
          rfc1157Domain  OBJECT IDENTIFIER ::= { rfc1157Proxy 1 }

          -- the community-based noAuth
          rfc1157noAuth  OBJECT IDENTIFIER ::= { rfc1157Proxy 2 }


          END






































          Case, McCloghrie, Rose & Waldbusser                   [Page 6]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          3.  SNMPv2 over UDP

          This is the preferred transport mapping.


          3.1.  Serialization

          Each instance of a message is serialized onto a single UDP[2]
          datagram, using the algorithm specified in Section 8.


          3.2.  Well-known Values

          Although the partyTable gives transport addressing information
          for an SNMPv2 party, it is suggested that administrators
          configure their SNMPv2 entities acting in an agent role to
          listen on UDP port 161.  Further, it is suggested that
          notification sinks be configured to listen on UDP port 162.

          The partyTable also lists the maximum message size which a
          SNMPv2 party is willing to accept.  This value must be at
          least 484 octets.  Implementation of larger values is
          encouraged whenever possible.



























          Case, McCloghrie, Rose & Waldbusser                   [Page 7]





          RFC 1449        Transport Mappings for SNMPv2       April 1993


          4.  SNMPv2 over OSI

          This is an optional transport mapping.


          4.1.  Serialization

          Each instance of a message is serialized onto a single TSDU
          [3,4] for the OSI Connectionless-mode Transport Service
          (CLTS), using the algorithm specified in Section 8.


          4.2.  Well-known Values

          Although the partyTable gives transport addressing information
          for an SNMPv2 party, it is suggested that administrators
          configure their SNMPv2 entities acting in an agent role to
          listen on transport selector "snmp-l" (which consists of six
          ASCII characters), when using a CL-mode network service to
          realize the CLTS.  Further, it is suggested that notification
          sinks be configured to listen on transport selector "snmpt-l"
          (which consists of seven ASCII characters) when using a CL-
          mode network service to realize the CLTS.  Similarly, when
          using a CO-mode network service to realize the CLTS, the
          suggested transport selectors are "snmp-o"  and "snmpt-o", for
          agent and notification sink, respectively.

          The partyTable also lists the maximum message size which a
          SNMPv2 party is willing to accept.  This value must be at
          least 484 octets.  Implementation of larger values is
          encouraged whenever possible.



















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          5.  SNMPv2 over DDP

          This is an optional transport mapping.


          5.1.  Serialization

          Each instance of a message is serialized onto a single DDP
          datagram [5], using the algorithm specified in Section 8.


          5.2.  Well-known Values

          SNMPv2 messages are sent using DDP protocol type 8.  SNMPv2
          entities acting in an agent role listens on DDP socket number
          8, whilst notification sinks listen on DDP socket number 9.

          Although the partyTable gives transport addressing information
          for an SNMPv2 party, administrators must configure their
          SNMPv2 entities acting in an agent role to use NBP type "SNMP
          Agent" (which consists of ten ASCII characters), whilst
          notification sinks must be configured to use NBP type "SNMP
          Trap Handler" (which consists of seventeen ASCII characters).

          The NBP name for agents and notification sinks should be
          stable - NBP names should not change any more often than the
          IP address of a typical TCP/IP node.  It is suggested that the
          NBP name be stored in some form of stable storage.

          The partyTable also lists the maximum message size which a
          SNMPv2 party is willing to accept.  This value must be at
          least 484 octets.  Implementation of larger values is
          encouraged whenever possible.


          5.3.  Discussion of AppleTalk Addressing

          The AppleTalk protocol suite has certain features not manifest
          in the TCP/IP suite.  AppleTalk's naming strategy and the
          dynamic nature of address assignment can cause problems for
          SNMPv2 entities that wish to manage AppleTalk networks.
          TCP/IP nodes have an associated IP address which distinguishes
          each from the other.  In contrast, AppleTalk nodes generally
          have no such characteristic.  The network-level address, while
          often relatively stable, can change at every reboot (or more





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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          frequently).

          Thus, when SNMPv2 is mapped over DDP, nodes are identified by
          a "name", rather than by an "address".  Hence, all AppleTalk
          nodes that implement this mapping are required to respond to
          NBP lookups and confirms (e.g., implement the NBP protocol
          stub), which guarantees that a mapping from NBP name to DDP
          address will be possible.

          In determining the SNMP identity to register for an SNMPv2
          entity, it is suggested that the SNMP identity be a name which
          is associated with other network services offered by the
          machine.

          NBP lookups, which are used to map NBP names into DDP
          addresses, can cause large amounts of network traffic as well
          as consume CPU resources.  It is also the case that the
          ability to perform an NBP lookup is sensitive to certain
          network disruptions (such as zone table inconsistencies) which
          would not prevent direct AppleTalk communications between two
          SNMPv2 entities.

          Thus, it is recommended that NBP lookups be used infrequently,
          primarily to create a cache of name-to-address mappings.
          These cached mappings should then be used for any further SNMP
          traffic.  It is recommended that SNMPv2 entities acting in a
          manager role should maintain this cache between reboots.  This
          caching can help minimize network traffic, reduce CPU load on
          the network, and allow for (some amount of) network trouble
          shooting when the basic name-to-address translation mechanism
          is broken.


          5.3.1.  How to Acquire NBP names

          An SNMPv2 entity acting in a manager role may have a pre-
          configured list of names of "known" SNMPv2 entities acting in
          an agent role.  Similarly, an SNMPv2 entity acting in a
          manager role might interact with an operator.  Finally, an
          SNMPv2 entity acting in a manager role might communicate with
          all SNMPv2 entities acting in an agent role in a set of zones
          or networks.








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          5.3.2.  When to Turn NBP names into DDP addresses

          When an SNMPv2 entity uses a cache entry to address an SNMP
          packet, it should attempt to confirm the validity mapping, if
          the mapping hasn't been confirmed within the last T1 seconds.
          This cache entry lifetime, T1, has a minimum, default value of
          60 seconds, and should be configurable.

          An SNMPv2 entity acting in a manager role may decide to prime
          its cache of names prior to actually communicating with
          another SNMPv2 entity.  In general, it is expected that such
          an entity may want to keep certain mappings "more current"
          than other mappings, e.g., those nodes which represent the
          network infrastructure (e.g., routers) may be deemed "more
          important".

          Note that an SNMPv2 entity acting in a manager role should not
          prime its entire cache upon initialization - rather, it should
          attempt resolutions over an extended period of time (perhaps
          in some pre-determined or configured priority order).  Each of
          these resolutions might, in fact, be a wildcard lookup in a
          given zone.

          An SNMPv2 entity acting in an agent role must never prime its
          cache.  Such an entity should do NBP lookups (or confirms)
          only when it needs to send an SNMP trap.  When generating a
          response, such an entity does not need to confirm a cache
          entry.


          5.3.3.  How to Turn NBP names into DDP addresses

          If the only piece of information available is the NBP name,
          then an NBP lookup should be performed to turn that name into
          a DDP address.  However, if there is a piece of stale
          information, it can be used as a hint to perform an NBP
          confirm (which sends a unicast to the network address which is
          presumed to be the target of the name lookup) to see if the
          stale information is, in fact, still valid.

          An NBP name to DDP address mapping can also be confirmed
          implicitly using only SNMP transactions.  For example, an
          SNMPv2 entity acting in a manager role issuing a retrieval
          operation could also retrieve the relevant objects from the
          NBP group [6] for the SNMPv2 entity acting in an agent role.





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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          This information can then be correlated with the source DDP
          address of the response.


          5.3.4.  What if NBP is broken

          Under some circumstances, there may be connectivity between
          two SNMPv2 entities, but the NBP mapping machinery may be
          broken, e.g.,

          o    the NBP FwdReq (forward NBP lookup onto local attached
               network) mechanism might be broken at a router on the
               other entity's network; or,

          o    the NBP BrRq (NBP broadcast request) mechanism might be
               broken at a router on the entity's own network; or,

          o    NBP might be broken on the other entity's node.

          An SNMPv2 entity acting in a manager role which is dedicated
          to AppleTalk management might choose to alleviate some of
          these failures by directly implementing the router portion of
          NBP.  For example, such an entity might already know all the
          zones on the AppleTalk internet and the networks on which each
          zone appears.  Given an NBP lookup which fails, the entity
          could send an NBP FwdReq to the network in which the agent was
          last located.  If that failed, the station could then send an
          NBP LkUp (NBP lookup packet) as a directed (DDP) multicast to
          each network number on that network.  Of the above (single)
          failures, this combined approach will solve the case where
          either the local router's BrRq-to-FwdReq mechanism is broken
          or the remote router's FwdReq-to-LkUp mechanism is broken.


















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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          6.  SNMPv2 over IPX

          This is an optional transport mapping.


          6.1.  Serialization

          Each instance of a message is serialized onto a single IPX
          datagram [7], using the algorithm specified in Section 8.


          6.2.  Well-known Values

          SNMPv2 messages are sent using IPX packet type 4 (i.e., Packet
          Exchange Packet).

          Although the partyTable gives transport addressing information
          for an SNMPv2 party, it is suggested that administrators
          configure their SNMPv2 entities acting in an agent role to
          listen on IPX socket 36879 (900f hexadecimal).  Further, it is
          suggested that notification sinks be configured to listen on
          IPX socket 36880 (9010 hexadecimal)

          The partyTable also lists the maximum message size which a
          SNMPv2 party is willing to accept.  This value must be at
          least 546 octets.  Implementation of larger values is
          encouraged whenever possible.























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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          7.  Proxy to SNMPv1

          In order to provide proxy to community-based SNMP [8], some
          definitions are necessary for both transport domains and
          authentication protocols.


          7.1.  Transport Domain: rfc1157Domain

          The transport domain, rfc1157Domain, indicates the transport
          mapping for community-based SNMP messages defined in RFC 1157.
          When a party's transport domain (partyTDomain) is
          rfc1157Domain:

          (1)  the party's transport address (partyTAddress) shall be 6
               octets long, the initial 4 octets containing the IP-
               address in network-byte order, and the last two octets
               containing the UDP port in network-byte order; and,

          (2)  the party's authentication protocol (partyAuthProtocol)
               shall be rfc1157noAuth.

          When a proxy relationship identifies a proxy destination party
          which has rfc1157Domain as its transport domain:

          (1)  the proxy source party (contextSrcPartyIndex) and proxy
               context (contextProxyContext) components of the proxy
               relationship are irrelevant; and,

          (2)  Section 3.1 of [9] specifies the behavior of the proxy
               agent.


          7.2.  Authentication Algorithm: rfc1157noAuth

          A party's authentication protocol (partyAuthProtocol)
          specifies the protocol and mechanism by which the party
          authenticates the integrity and origin of the SNMPv1 or SNMPv2
          PDUs it generates.  When a party's authentication protocol is
          rfc1157noAuth:

          (1)  the party's public authentication key (partyAuthPublic),
               clock (partyAuthClock), and lifetime (partyAuthLifetime)
               are irrelevant; and,






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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          (2)  the party's private authentication key
               (partySecretsAuthPrivate) shall be used as the 1157
               community for the proxy destination, and shall be at
               least one octet in length.  (No maximum length is
               specified.)

          Note that when setting the party's private authentication key,
          the exclusive-OR semantics specified in [10] still apply.










































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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          8.  Serialization using the Basic Encoding Rules

          When the Basic Encoding Rules [11] are used for serialization:

          (1)  When encoding the length field, only the definite form is
               used; use of the indefinite form encoding is prohibited.
               Note that when using the definite-long form, it is
               permissible to use more than the minimum number of length
               octets necessary to encode the length field.

          (2)  When encoding the value field, the primitive form shall
               be used for all simple types, i.e., INTEGER, OCTET
               STRING, OBJECT IDENTIFIER, and BIT STRING (either
               IMPLICIT or explicit).  The constructed form of encoding
               shall be used only for structured types, i.e., a SEQUENCE
               or an IMPLICIT SEQUENCE.

          (3)  When a BIT STRING is serialized, all named-bits are
               transferred regardless of their truth-value.  Further, if
               the number of named-bits is not an integral multiple of
               eight, then the fewest number of additional zero-valued
               bits are transferred so that an integral multiple of
               eight bits is transferred.

          These restrictions apply to all aspects of ASN.1 encoding,
          including the message wrappers, protocol data units, and the
          data objects they contain.























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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          8.1.  Usage Example

          As an example of applying the Basic Encoding Rules, suppose
          one wanted to encode an instance of the GetBulkRequest-PDU
          [1]:

               [5] IMPLICIT SEQUENCE {
                       request-id      1414684022,
                       non-repeaters   1,
                       max-repetitions 2,
                       variable-bindings {
                           { name sysUpTime,
                             value { unspecified NULL } },
                           { name ipNetToMediaPhysAddress,
                             value { unspecified NULL } },
                           { name ipNetToMediaType,
                             value { unspecified NULL } }
                       }
                   }

          Applying the BER, this would be encoded (in hexadecimal) as:

          [5] IMPLICIT SEQUENCE          a5 82 00 39
              INTEGER                    02 04 52 54 5d 76
              INTEGER                    02 01 01
              INTEGER                    02 01 02
              SEQUENCE                   30 2b
                  SEQUENCE               30 0b
                      OBJECT IDENTIFIER  06 07 2b 06 01 02 01 01 03
                      NULL               05 00
                  SEQUENCE               30 0d
                      OBJECT IDENTIFIER  06 09 2b 06 01 02 01 04 16 01 02
                      NULL               05 00
                  SEQUENCE               30 0d
                      OBJECT IDENTIFIER  06 09 2b 06 01 02 01 04 16 01 04
                      NULL               05 00

          Note that the initial SEQUENCE is not encoded using the
          minimum number of length octets.  (The first octet of the
          length, 82, indicates that the length of the content is
          encoded in the next two octets.)









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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          9.  Acknowledgements

          The UDP-based mapping is based, in part, on RFC 1157.

          The OSI-based mapping is based, in part, on RFC 1283.

          The DDP-based mapping is based, in part, on earlier work by
          Greg Minshall of Novell, Inc., and Mike Ritter of Apple
          Computer, Inc.

          The IPX-based mapping is based, in part, on RFC 1298.

          The section on proxy to community-based SNMP is based on
          earlier work that was based in part on a suggestion by
          Jonathan Biggar of Netlabs, Inc.

          Finally, the comments of the SNMP version 2 working group are
          gratefully acknowledged:

               Beth Adams, Network Management Forum
               Steve Alexander, INTERACTIVE Systems Corporation
               David Arneson, Cabletron Systems
               Toshiya Asaba
               Fred Baker, ACC
               Jim Barnes, Xylogics, Inc.
               Brian Bataille
               Andy Bierman, SynOptics Communications, Inc.
               Uri Blumenthal, IBM Corporation
               Fred Bohle, Interlink
               Jack Brown
               Theodore Brunner, Bellcore
               Stephen F. Bush, GE Information Services
               Jeffrey D. Case, University of Tennessee, Knoxville
               John Chang, IBM Corporation
               Szusin Chen, Sun Microsystems
               Robert Ching
               Chris Chiotasso, Ungermann-Bass
               Bobby A. Clay, NASA/Boeing
               John Cooke, Chipcom
               Tracy Cox, Bellcore
               Juan Cruz, Datability, Inc.
               David Cullerot, Cabletron Systems
               Cathy Cunningham, Microcom
               James R. (Chuck) Davin, Bellcore
               Michael Davis, Clearpoint





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          RFC 1449        Transport Mappings for SNMPv2       April 1993


               Mike Davison, FiberCom
               Cynthia DellaTorre, MITRE
               Taso N. Devetzis, Bellcore
               Manual Diaz, DAVID Systems, Inc.
               Jon Dreyer, Sun Microsystems
               David Engel, Optical Data Systems
               Mike Erlinger, Lexcel
               Roger Fajman, NIH
               Daniel Fauvarque, Sun Microsystems
               Karen Frisa, CMU
               Shari Galitzer, MITRE
               Shawn Gallagher, Digital Equipment Corporation
               Richard Graveman, Bellcore
               Maria Greene, Xyplex, Inc.
               Michel Guittet, Apple
               Robert Gutierrez, NASA
               Bill Hagerty, Cabletron Systems
               Gary W. Haney, Martin Marietta Energy Systems
               Patrick Hanil, Nokia Telecommunications
               Matt Hecht, SNMP Research, Inc.
               Edward A. Heiner, Jr., Synernetics Inc.
               Susan E. Hicks, Martin Marietta Energy Systems
               Geral Holzhauer, Apple
               John Hopprich, DAVID Systems, Inc.
               Jeff Hughes, Hewlett-Packard
               Robin Iddon, Axon Networks, Inc.
               David Itusak
               Kevin M. Jackson, Concord Communications, Inc.
               Ole J. Jacobsen, Interop Company
               Ronald Jacoby, Silicon Graphics, Inc.
               Satish Joshi, SynOptics Communications, Inc.
               Frank Kastenholz, FTP Software
               Mark Kepke, Hewlett-Packard
               Ken Key, SNMP Research, Inc.
               Zbiginew Kielczewski, Eicon
               Jongyeoi Kim
               Andrew Knutsen, The Santa Cruz Operation
               Michael L. Kornegay, VisiSoft
               Deirdre C. Kostik, Bellcore
               Cheryl Krupczak, Georgia Tech
               Mark S. Lewis, Telebit
               David Lin
               David Lindemulder, AT&T/NCR
               Ben Lisowski, Sprint
               David Liu, Bell-Northern Research





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          RFC 1449        Transport Mappings for SNMPv2       April 1993


               John Lunny, The Wollongong Group
               Robert C. Lushbaugh Martin, Marietta Energy Systems
               Michael Luufer, BBN
               Carl Madison, Star-Tek, Inc.
               Keith McCloghrie, Hughes LAN Systems
               Evan McGinnis, 3Com Corporation
               Bill McKenzie, IBM Corporation
               Donna McMaster, SynOptics Communications, Inc.
               John Medicke, IBM Corporation
               Doug Miller, Telebit
               Dave Minnich, FiberCom
               Mohammad Mirhakkak, MITRE
               Rohit Mital, Protools
               George Mouradian, AT&T Bell Labs
               Patrick Mullaney, Cabletron Systems
               Dan Myers, 3Com Corporation
               Rina Nathaniel, Rad Network Devices Ltd.
               Hien V. Nguyen, Sprint
               Mo Nikain
               Tom Nisbet
               William B. Norton, MERIT
               Steve Onishi, Wellfleet Communications, Inc.
               David T. Perkins, SynOptics Communications, Inc.
               Carl Powell, BBN
               Ilan Raab, SynOptics Communications, Inc.
               Richard Ramons, AT&T
               Venkat D. Rangan, Metric Network Systems, Inc.
               Louise Reingold, Sprint
               Sam Roberts, Farallon Computing, Inc.
               Kary Robertson, Concord Communications, Inc.
               Dan Romascanu, Lannet Data Communications Ltd.
               Marshall T. Rose, Dover Beach Consulting, Inc.
               Shawn A. Routhier, Epilogue Technology Corporation
               Chris Rozman
               Asaf Rubissa, Fibronics
               Jon Saperia, Digital Equipment Corporation
               Michael Sapich
               Mike Scanlon, Interlan
               Sam Schaen, MITRE
               John Seligson, Ultra Network Technologies
               Paul A. Serice, Corporation for Open Systems
               Chris Shaw, Banyan Systems
               Timon Sloane
               Robert Snyder, Cisco Systems
               Joo Young Song





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          RFC 1449        Transport Mappings for SNMPv2       April 1993


               Roy Spitier, Sprint
               Einar Stefferud, Network Management Associates
               John Stephens, Cayman Systems, Inc.
               Robert L. Stewart, Xyplex, Inc. (chair)
               Kaj Tesink, Bellcore
               Dean Throop, Data General
               Ahmet Tuncay, France Telecom-CNET
               Maurice Turcotte, Racal Datacom
               Warren Vik, INTERACTIVE Systems Corporation
               Yannis Viniotis
               Steven L. Waldbusser, Carnegie Mellon Universitty
               Timothy M. Walden, ACC
               Alice Wang, Sun Microsystems
               James Watt, Newbridge
               Luanne Waul, Timeplex
               Donald E. Westlake III, Digital Equipment Corporation
               Gerry White
               Bert Wijnen, IBM Corporation
               Peter Wilson, 3Com Corporation
               Steven Wong, Digital Equipment Corporation
               Randy Worzella, IBM Corporation
               Daniel Woycke, MITRE
               Honda Wu
               Jeff Yarnell, Protools
               Chris Young, Cabletron
               Kiho Yum, 3Com Corporation
























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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          10.  References

          [1]  Case, J., McCloghrie, K., Rose, M., and Waldbusser, S.,
               "Protocol Operations for version 2 of the Simple Network
               Management Protocol (SNMPv2)", RFC 1448, SNMP Research,
               Inc., Hughes LAN Systems, Dover Beach Consulting, Inc.,
               Carnegie Mellon University, April 1993.

          [2]  Postel, J., "User Datagram Protocol", STD 6, RFC 768,
               USC/Information Sciences Institute, August 1980.

          [3]  Information processing systems - Open Systems
               Interconnection - Transport Service Definition,
               International Organization for Standardization.
               International Standard 8072, (June, 1986).

          [4]  Information processing systems - Open Systems
               Interconnection - Transport Service Definition - Addendum
               1: Connectionless-mode Transmission, International
               Organization for Standardization.  International Standard
               8072/AD 1, (December, 1986).

          [5]  G. Sidhu, R. Andrews, A. Oppenheimer, Inside AppleTalk
               (second edition).  Addison-Wesley, 1990.

          [6]  Waldbusser, S., "AppleTalk Management Information Base",
               RFC 1243, Carnegie Mellon University, July 1991.

          [7]  Network System Technical Interface Overview.  Novell,
               Inc, (June, 1989).

          [8]  Case, J., Fedor, M., Schoffstall, M., Davin, J., "Simple
               Network Management Protocol", STD 15, RFC 1157, SNMP
               Research, Performance Systems International, MIT
               Laboratory for Computer Science, May 1990.

          [9]  Case, J., McCloghrie, K., Rose, M., and Waldbusser, S.,
               "Coexistence between version 1 and version 2 of the
               Internet-standard Network Management Framework", RFC
               1452, SNMP Research, Inc., Hughes LAN Systems, Dover
               Beach Consulting, Inc., Carnegie Mellon University, April
               1993.

          [10] McCloghrie, K., and Galvin, J., "Party MIB for version 2
               of the Simple Network Management Protocol (SNMPv2)", RFC





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          RFC 1449        Transport Mappings for SNMPv2       April 1993


               1447, Hughes LAN Systems, Trusted Information Systems,
               April 1993.

          [11] Information processing systems - Open Systems
               Interconnection - Specification of Basic Encoding Rules
               for Abstract Syntax Notation One (ASN.1), International
               Organization for Standardization.  International Standard
               8825, (December, 1987).










































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          RFC 1449        Transport Mappings for SNMPv2       April 1993


          11.  Security Considerations

          Security issues are not discussed in this memo.


          12.  Authors' Addresses

               Jeffrey D. Case
               SNMP Research, Inc.
               3001 Kimberlin Heights Rd.
               Knoxville, TN  37920-9716
               US

               Phone: +1 615 573 1434
               Email: case@snmp.com


               Keith McCloghrie
               Hughes LAN Systems
               1225 Charleston Road
               Mountain View, CA  94043
               US

               Phone: +1 415 966 7934
               Email: kzm@hls.com


               Marshall T. Rose
               Dover Beach Consulting, Inc.
               420 Whisman Court
               Mountain View, CA  94043-2186
               US

               Phone: +1 415 968 1052
               Email: mrose@dbc.mtview.ca.us

               Steven Waldbusser
               Carnegie Mellon University
               4910 Forbes Ave
               Pittsburgh, PA  15213
               US

               Phone: +1 412 268 6628
               Email: waldbusser@cmu.edu






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