Network Working Working Group
Request for Comments: 1189
Obsoletes: RFC 1095
U. Warrier
Netlabs
L. Besaw
Hewlett-Packard
L. LaBarre
The Mitre Corporation
B. Handspicker
Digital Equipment Corporation
October 1990

The Common Management Information Services

and Protocols for the Internet

(CMOT and CMIP)

Status of this Memo

This memo defines a network management architecture that uses the International Organization for Standardization's (ISO) Common Management Information Services/Common Management Information Protocol (CMIS/CMIP) in the Internet. This RFC specifies 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. Overview ...................................................    2
   2. Introduction ...............................................    3
   3. Protocol Overview ..........................................    4
   3.1. The CMOT Protocol Suite ..................................    5
   3.2. The CMIP Protocol Suite ..................................    6
   3.3. Conformance Requirements .................................    6
   4. Common Management Information Service Element ..............    7
   4.1. Association Policies .....................................    7
   4.2. CMIS Services ............................................    9
   4.2.1 General Agreements on Users of CMIS .....................    9
   4.2.2 Specific Agreements on Users of CMIS ....................   10
   4.3. CMIP Agreements ..........................................   10
   5. Services Required by CMIP ..................................   10
   6. Acknowledgements ...........................................   11
   7. References .................................................   11
   8. Security Considerations.....................................   14
   9. Authors' Addresses..........................................   14

1. Overview

This memo is a revision of RFC 1095 - "The Common Management Information Services and Protocol over TCP/IP" [27]. It defines a network management architecture that uses the International Organization for Standardization's (ISO) Common Management Information Services/Common Management Information Protocol (CMIS/CMIP) in the Internet. This architecture provides a means by which control and monitoring information can be exchanged between a manager and a remote network element. In particular, this memo defines the means for implementing the International Standard (IS) version of CMIS/CMIP on top of both IP-based and OSI-based Internet transport protocols for the purpose of carrying management information defined in the Internet-standard management information base. Together with the relevant ISO standards and the companion RFCs that describe the initial structure of management information and management information base, these documents provide the basis for a comprehensive architecture and system for managing both IP- based and OSI-based internets, and in particular the Internet.

In creating this revision of RFC 1095, the following technical and editorial changes were made:

  1. The tutorial section on OSI Management included in RFC 1095 has been removed from this document. After some revisions, the tutorial material may be published as another RFC.
  1. The sections in RFC 1095 which discussed the semantics of how to interpret requests in the context of Internet MIBs has been removed from this protocol document. This topic is now discussed in the OIM-MIB-II draft document. This protocol should be useable with MIB-I or MIB-II. But, it will also be able to exploit the new features of the OIM-MIB-II.
  1. This document is based on the final International Standards for CMIS/CMIP (ISO 9595/9596) rather than the Draft International Standards.
  1. Many of the original agreements defined in RFC 1095 have been accepted and included in the OIW NMSIG implementers agreements. Rather than duplicating these agreements, they have been removed from this memo. This document should be read in conjunction with ISO 9595/9596 (CMIS/CMIP) and the OIW Stable Agreements document.
  1. The Association Negotiation describe in RFC 1095 has been changed to align with current international and national agreements. But, it has retained backwards compatibility with the assignment of an Application Context Name which is identical to the Application Context Name specified in RFC 1095.

2. Introduction

This memo is the output of the OSI Internet Management Working Group of the Internet Engineering Task Force (IETF). As directed by the Internet Activites Board (IAB) in RFC 1052, it addresses the need for a long-term network management system based on ISO CMIS/CMIP. This memo contains a set of protocol agreements for implementing a network management system based on these ISO Management standards. Now that CMIS/CMIP has been voted an International Standard (IS), it has become a stable basis for product development. This profile specifies how to apply CMIP to management of both IP-based and OSI- based Internet networks. Network management using ISO CMIP to manage IP-based networks will be refered to as "CMIP Over TCP/IP" (CMOT). Network management using ISO CMIP to manage OSI-based networks will be refered to as "CMIP". This memo specifies the protocol agreements necessary to implement CMIP and accompanying ISO protocols over OSI, TCP and UDP transport protocols.

This memo must be read in conjunction with ISO and Internet documents defining specific protocol standards. Documents defining the following ISO standards are required for the implementor: Abstract Syntax Notation One (ASN.1) [5, 6], Association Control (ACSE) [7, 8], Remote Operations (ROSE) [9, 10], Common Management Information Services (CMIS) [11] and Common Management Information Protocol (CMIP) [12] with their addenda [32-35]. The specification of a lightweight presentation layer protocol is required for use with the CMOT section of this profile (see RFC 1085 [13]). The SMI (see RFC 1065 [2]), the MIB-I (see RFC 1066 [3]), the MIB-II (see RFC 1156 [28]), and the OIM-MIB-II (see [29]) are used with this management system.

This memo is divided into sections for each of the protocols for which implementors' agreements are needed: CMISE, ACSE, ROSE, and, for CMOT, the lightweight presentation protocol. The protocol profile defined in this memo draws on the technical work of the OSI Network Management Forum [14] and the Network Management Special Interest Group (NMSIG) of the National Institute of Standards and Technology (NIST) (formerly the National Bureau of Standards) [30]. Wherever possible, an attempt has been made to either directly reference or remain consistent with the protocol agreements reached by these groups.

3. Protocol Overview

This part of the document is a specification of the protocols of the OIM architecture. Contained herein are the agreements required to implement interoperable network management systems using these protocols. The protocol suite defined by these implementors' agreements will facilitate communication between equipment of different vendors, suppliers, and networks. This will allow the emergence of powerful multivendor network management based on ISO models and protocols.

   The choice of a set of protocol standards together with further
   agreements needed to implement those standards is commonly referred
   to as a "profile."  The selection policy for this profile is to use
   existing standards from the international standards community (ISO
   and CCITT) and the Internet community.  Existing ISO standards and
   draft standards in the area of OSI network management form the basis
   of this profile.  Other ISO application layer standards (ROSE and
   ACSE) are used to support the ISO management protocol (CMIP).  To
   ensure interoperability, certain choices and restrictions are made
   here concerning various options and parameters provided by these
   standards.   Internet standards are used to provide the underlying
   network transport.  These agreements provide a precise statement of
   the implementation choices made for implementing ISO network
   management standards in IP-based and OSI-based internets.

In addition to the OIM working group, there are at least two other bodies actively engaged in defining profiles for interoperable OSI network management: the OSI Implementors Workshop (OIW) and the OSI Network Management Forum. Both of these groups are similar to the OIM working group in that they are each defining profiles for using ISO standards for network management. Both differ in that they are specifying the use only of underlying ISO protocols, while the OIM working group is concerned with using OSI management in both OSI and TCP/IP networks. In the interest of greater future compatibility, the OIM working group has attempted to make this profile conform as closely as possible to the ongoing work of these two bodies.

This section will describe the CMOT Protocol Suite, the CMIP Protocol Suite and Conformance Requirements common to both CMOT and CMIP. Later sections will specify the implementers agreements for specific layer protocols that comprise the CMOT and CMIP Protocol Suites.

3.1. The CMOT Protocol Suite

The following seven protocols compose the CMOT protocol suite: ISO ACSE, ISO DIS ROSE, ISO CMIP, the lightweight presentation protocol (LPP), UDP, TCP, and IP. The relation of these protocols to each other is briefly summarized in Figure 2.

                 +----------------------------------------------+
                         Management Application Processes
                 +----------------------------------------------+
                 
                             +-------------------+
                                     CMISE
                                 ISO 9595/9596
                             +-------------------+
                 
                 +------------------+       +--------------------+
                          ACSE                       ROSE
                   ISO IS 8649/8650           ISO DIS 9072-1/2
                 +------------------+       +--------------------+
                 
                 +-----------------------------------------------+
                       Lightweight Presentation Protocol (LPP)
                                     RFC 1085
                 +-----------------------------------------------+
                 
                 +------------------+       +--------------------+
                         TCP                         UDP
                       RFC 793                     RFC 768
                 +------------------+       +--------------------+
                 
                 +-----------------------------------------------+
                                       IP
                                     RFC 791
                 +-----------------------------------------------+

Figure 2. The CMOT Protocol Suite

3.2. The CMIP Protocol Suite

   The following six protocols compose the CMIP protocol suite: ISO
   ACSE, ISO DIS ROSE, ISO CMIP, ISO Presentation, ISO  Session and ISO
   Transport.  The relation of these protocols to each other is briefly
   summarized in Figure 3.
   
                 +----------------------------------------------+
                         Management Application Processes
                 +----------------------------------------------+
   
                             +-------------------+
                                     CMISE
                                 ISO 9595/9596
                             +-------------------+
   
                 +------------------+       +--------------------+
                          ACSE                       ROSE
                     ISO 8649/8650            ISO DIS 9072-1/2
                 +------------------+       +--------------------+
   
                 +-----------------------------------------------+
                                ISO Presentation
                                    ISO
                 +-----------------------------------------------+
   
                 +-----------------------------------------------+
                                ISO Session
                                    ISO
                 +-----------------------------------------------+
   
                 +-----------------------------------------------+
                                ISO Transport
                                    ISO
                 +-----------------------------------------------+

Figure 3. The CMIP Protocol Suite

3.3. Conformance Requirements

A CMOT-conformant system must implement the following protocols: ACSE, ROSE, CMIP, LPP, and IP. A CMOT-conformant system must support the use of the LPP over either UDP or TCP. The use of the LPP over both UDP and TCP on the same system may be supported.

A CMIP-conformant system must implement the following protocols: ACSE, ROSE, CMIP, ISO Presentation, ISO Session and ISO Transport.

4. Common Management Information Service Element

The Common Management Information Service Element (CMISE) is specified in two ISO documents. The service definition for the Common Management Information Service (CMIS) is given in ISO 9595 [11]. The protocol specification for the Common Management Information Protocol (CMIP) is found in ISO 9596 [12]. In addition, the addenda for add/remove support in M-SET [32, 34] must be supported for both CMOT and CMIP. The addenda for M-CANCEL-GET [33, 35] may be supported by an implementation, but it's use is negotiated as part of association negotiation.

4.1. Association Policies

   The following ACSE services are required by CMISE: A-ASSOCIATE, A-
   RELEASE, A-ABORT, and A-P-ABORT.  The rest of the CMIP protocol uses
   the RO-INVOKE, RO-RESULT, RO-ERROR, and RO-REJECT services of ROSE.

There are four types of association that may be negotiated between managing and managed systems. These types are:

      Event               M-EVENT-REPORTs may be sent by the
                          managed system; no other CMIP PDUs
                          are allowed
      
      Event/Monitor       same as Event type except that, in
                          addition, the managing system may
                          also issue M-GET requests and
                          receive M-GET responses over the
                          association
      
      Monitor/Control     managing system may issue M-GET,
                          M-SET, M-CREATE, M-DELETE and
                          M-ACTION requests over the
                          association; no event reporting is
                          allowed
      
      Full Mgr/Agent      all functions must be supported
   
   A conformant system  must support at least one of these Association
   types.  Note that a system may play both managing and managed system
   roles, but not on the same association.

The negotiation process uses the A-ASSOCIATE and A-RELEASE services. Application Context Name is used to determine the requestor's "role" in an association (as managing or managed system) and to determine the type of the association.

The following values for Application Context Name are registered for for CMOT and CMIP:

      {iso(1) identified-organization(3) dod(6)
           internet(1) mgmt(2) mib(1) oim(9) acn(1)
           cmot1095(1)}
           (for backwards compatible negotiation with RFC 1095 CMOT
           implementations)
      
      {iso(1) identified-organization(3) dod(6)
           internet(1) mgmt(2) mib(1) oim(9) acn(1)
           manager-event-association(2)}
      
      {iso(1) identified-organization(3) dod(6)
           internet(1) mgmt(2) mib(1) oim(9) acn(1)
           manager-event-monitor-association(3)}
      
      {iso(1) identified-organization(3) dod(6)
           internet(1) mgmt(2) mib(1) oim(9) acn(1)
           manager-monitor-control-association(4)}
      
      {iso(1) identified-organization(3) dod(6)
           internet(1) mgmt(2) mib(1) oim(9) acn(1)
           manager-full-association(5)}
      
      {iso(1) identified-organization(3) dod(6)
           internet(1) mgmt(2) mib(1) oim(9) acn(1)
           agent-event-association(6)}

The following negotiation rules are to be used:

      1.   A managed system may only request an Event
           association and, in fact, must create an Event
           association if it has an event to report and no
           suitable association already exists.
      
      2.   Managing systems may request any association type.
      
      3.   An association is created by the requesting system
           issuing an A-ASSOCIATE request with the
           requestor's AE-TITLE and the desired application
           context.  The responding system then returns
           either 1) an A-ASSOCIATE response with the
           requestor's AE-TITLE and the application context
           which it wishes to accept or 2) an A-ASSOCIATE
           response rejecting the association.
      
      4.   Managed systems may negotiate "downward" from
           Full to Monitor/Control, Event/Monitor or Event by
           returning the new application context in the
           A-ASSOCIATE response to the managing system during
           the association creation process.  In the same
           fashion, managed systems may negotiate from
           Event/Monitor to Event.
      
      5.   When a managing system receives an application
           context in an A-ASSOCIATE response that differs
           from the context sent in an A-ASSOCIATE request it
           may either proceed with the new context or refuse
           the new context by issuing an A-RELEASE request.

A-RELEASE is used when the requestor does not agree with the new context. A-ABORT is used for invalid negotiation. If A-ABORT were to be used to terminate an association, there exists the potential for loss of information, such as pending events or confirmations. A-ABORT must be used, however, when a protocol violation occurs or where an association is not yet established.

4.2. CMIS Services

4.2.1 General Agreements on Users of CMIS

The general agreements on users of CMIS shall be as specified in the OIW Stable Agreements [30] section 18.6.2.

The following additional agreements are specified.

  • A system need only implement the services and service primitives required for the association types (section 4.1) that it supports.
  • Current/Event times shall be fields shall use 1 millisecond granularity. If the system generating the PDU does not have the current time, yet does have the time since last boot, then GeneralizedTime can be used to encode this information. The time since last boot will be added to the base time "0001 Jan 1 00:00:00.00" using the Gregorian calendar algorithm. (In the Gregorian calendar, all years have 365 days except those divisible by 4 and not by 400, which have 366.) The use of the year 1 as the base year will prevent any confusion with current time.

If no meaningful time is available, then the year 0 shall be used in GeneralizedTime to indicate this fact.

4.2.2 Specific Agreements on Users of CMIS

The specific agreements on users of CMIS shall be as specified in the OIW Stable Agreements [30] section 18.6.3.

The following additional agreements are specified:

  • Event time shall be mandatory for all events.
  • Both the "managed Object Class" and "managed Object Instance" parameters must be present in the following CMIS Service Response/Confirmation primitives: the M-EVENT-REPORT Confirmed, the M-GET, the M-SET, the M-ACTION, the M-CREATE, and the M-DELETE.

4.3. CMIP Agreements

The CMIS and CMIP implementers agreements documented in the OIW Stable Implementers Agreements [30] plus those mandated by the CMIP standard will be used for both CMOT and CMIP. In addition to these implementers agreements, the following specific agreements must be observed:

  • An implementation is required to support all filter items except subsetOf, supersetOf, nonNullSetIntersection, and substrings.
  • The "managedObjectInstance" field must be present in the ProcessingFailure Error PDU. The "managedObjectClass" field must be present in the NoSuchArgument Error PDU.
   [Temporary Note:  The CMIS/P implementers agreements have reach a
   fairly stable status in the OIW working agreements document.  It is
   expected that the CMIS/P agreements (18.6.2 and 18.6.3) will be
   recommended to be moved into the stable agreements document during
   either the June 1990 meetings.  Reference [30] points to the presumed
   June 1990 updated version of the stable agreements document.]

5. Services Required by CMIP

The services required by CMIP shall be as specified in the OIW Stable Implementors Agreements [30] section 18.6.5.

The following additional agreements are specified:

      o ASCE Requirements:  Application contexts shall be as defined
      
        in section 4.1 of these agreements.  The values and defaults

of parameters to the ACSE parameters given to the presentation service are specified in RFC 1085 [13] for CMOT and in the NIST Stable Implementers Agreements [30] for CMIP.

      o Presentation Requirements:  CMOT implementations shall be
        supported by the Lightweight Presentation Protocol (LPP)
        [13].  The LPP may use either TCP or UDP.  When UDP is used,
        an implementation need not accept LPP PDUs whose length
        exceeds 484 octets.
      
      o Session Requirements:  CMOT implementations will not
        require the session protocol.

6. Acknowledgements

This RFC is the result of the work of many people. The following members of the IETF OSI Internet Management and preceding Netman working groups made important contributions:

Amatzia Ben-Artzi, Synoptics
Asheem Chandna, AT&T Bell Laboratories
Ken Chapman, Digital Equipment Corporation Anthony Chung, Sytek
George Cohn, Ungermann-Bass
Gabriele Cressman, Sun Microsystems
Tom Halcin, Hewlett-Packard
Pranati Kapadia, Hewlett-Packard
Lee LaBarre, The MITRE Corporation (co-chair) Dave Mackie, 3Com
Keith McCloghrie, Hughes/InterLan
Jim Robertson, 3Com
Milt Roselinsky, CMC
Marshall Rose, PSI
John Scott, Data General
Lou Steinberg, IBM

7. References

   [1] Cerf, V., "IAB Recommendations for the Development of Internet
   
       Network Management Standards", RFC 1052, IAB, April 1988.
   
   [2] Rose, M., and K. McCloghrie, "Structure and Identification of
       Management Information for TCP/IP-based internets", RFC 1065,
       TWG, August 1988.
   
   [3] McCloghrie, K., and M. Rose, "Management Information Base for
       Network Management of TCP/IP-based internets", RFC 1066, TWG,
       August 1988.
   
   [4] Case, J., M. Fedor, M. Schoffstall, and J. Davin, "A Simple
       Network Management Protocol (SNMP)", RFC 1098, (Obsoletes RFC
       1067), University of Tennessee at Knoxville, NYSERNet, Inc.,
       Rensselaer Polytechnic Institute, MIT Laboratory for Computer
       Science, April 1989.

[5] ISO 8824: "Information Processing Systems - Open Systems

Interconnection, Specification of Abstract Syntax Notation One (ASN.1)", Geneva, March 1988.

[6] ISO 8825: "Information Processing Systems - Open Systems

Interconnection, Specification of Basic Encoding Rules for Abstract Notation One (ASN.1)", Geneva, March 1988.

[7] ISO 8649: "Information Processing Systems - Open Systems

Interconnection, Service Definition for Association Control Service Element".

[8] ISO 8650: "Information Processing Systems - Open Systems

Interconnection, Protocol Specification for Association Control Service Element".

[9] CCITT Recommendation X.219, Working Document for ISO 9072-1:

"Information processing systems - Text Communication, Remote Operations: Model, Notation and Service Definition", Gloucester, November 1987.

[10] CCITT Recommendation X.229, Working Document for ISO 9072-2:

"Information processing systems - Text Communication, Remote Operations: Protocol Specification", Gloucester, November 1987.

[11] ISO 9595: "Information Processing Systems - Open Systems

Interconnection, Management Information Service Definition - Part 2: Common Management Information Service", 22 December 1988.

[12] ISO 9596: "Information Processing Systems - Open Systems

Interconnection, Management Information Protocol Specification - Part 2: Common Management Information Protocol", 22 December 1988.

  [13] Rose, M., "ISO Presentation Services on top of TCP/IP-based
       internets", RFC 1085, TWG, December 1988.
  
  [14] OSI Network Management Forum, "Forum Interoperable Interface
       Protocols", September 1988.
  
  [15] ISO DIS 7498-4: "Information Processing Systems - Open Systems
       Interconnection, Basic Reference Model - Part 4: OSI Management

Framework".

  [16] ISO/IEC JTC1/SC21/WG4 N571: "Information Processing Systems -
       Open Systems Interconnection, Systems Management: Overview",
       London, July 1988.
  
  [17] Klerer, S. Mark, "The OSI Management Architecture: An Overview",
       IEEE Network Magazine, March 1988.
  
  [18] Ben-Artzi, A., "Network Management for TCP/IP Networks: An
       Overview", Internet Engineering Task Force working note, April
       1988.
  
  [19] ISO/IEC JTC1/SC21/WG4 N3324: "Information Processing Pystems -
       Open Systems Interconnection, Management Information Services -
       Structure of Management Information - Part I: Management
       Information Model", Sydney, December 1988.
  
  [20] Postel, J., "User Datagram Protocol", RFC 768, USC/Information
       Sciences Institute, August 1980.
  
  [21] Postel, J., "Transmission Control Protocol", RFC 793,
       USC/Information Sciences Institute, September 1981.
  
  [22] ISO DP 9534: "Information processing systems - Open Systems
       Interconnection, Application Layer Structure", 10 March 1987.
  
  [23] Rose, M., and D. Cass, "ISO Transport Services on top of the TCP,
       Version: 3", RFC 1006, Northrop Research and Technology Center,
       May 1987.

[24] ISO 8822: "Information Processing Systems - Open Systems

Interconnection, Connection Oriented Presentation Service Definition", June 1987.

  [25] Postel, J., "Internet Protocol", RFC 791, USC/Information
       Sciences Institute, September 1981.
  
  [26] CCITT Draft Recommendation X.500, ISO 9594/1-8: "The Directory",
       Geneva, March 1988.
  
  [27] Warrier, U. and L. Besaw, "The Common Management Information
       Services and Protocol over TCP/IP (CMOT)", RFC 1095, Unisys
       Corporation, Hewlett-Packard, April 1989.
  
  [28] McCloghrie, K., and M. Rose, "Management Information Base for
       Network Management of TCP/IP-based internets", RFC 1156, Hughes
       LAN Systems, Performance Systems International, May 1990.
  
  [29]  LaBarre, L., "OIM MIB-II", working note, December 1989.
  
  [30] NIST NMSIG, "NIST Stable Implementers Agreements", NIST Special
       Publication 500-162, as ammended by June 1990.
  
  [31] NIST NMSIG, "NIST Working Implementers Agreements", December
       1989.

[32] ISO IS 9595 1989: DAD1: "CMIS Add/Remove Addendum".

[33] ISO IS 9595 1989: DAD2: "CMIS Cancel-Get Addendum".

[34] ISO IS 9596 1989: DAD1: "CMIP Add/Remove Addendum".

[35] ISO IS 9596 1989: DAD2: "CMIP Cancel-Get Addendum".

8. Security Considerations

Security issues are not discussed in this memo.

9. Authors' Addresses

Unnikrishnan S. Warrier
NetLabs
11693 San Vicente Blvd
Suite 348
Los Angeles, CA 90049

   Phone: (213) 476-4070
   Email: unni@netlabs.com

Larry Besaw
Hewlett-Packard
3404 East Harmony Road
Fort Collins, CO 80525

   Phone: (303) 229-6022
   Email: lmb%hpcndaw@hplabs.hp.com

Lee LaBarre
Mitre
Burlington Road
Bedford, MA 01730

   Phone: (617) 271-8507
   Email: cel@mbunix.mitre.org

Brian D. Handspicker
Digital Equipment Corporation
550 King St.
Littleton, Ma. 01460

   Phone: (508) 486-7894
   Email: bd@vines.enet.dec.com