Forwarding and Control Element                                   R. Haas
Separation (forces)                                                  IBM

Intended status: Standards Track
Expires: January 5, 28, 2007

                               ForCES MIB
                        draft-ietf-forces-mib-03
                        draft-ietf-forces-mib-04

Status of this Memo

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   This Internet-Draft will expire on January 5, 28, 2007.

Copyright Notice

   Copyright (C) The Internet Society (2006).

Abstract

   This memo defines a Management Information Base (MIB) module for use
   with network management protocols in the Internet community.  In
   particular, it defines a MIB managed objects for the Forwarding and Control
   Element Separation (ForCES) Network Element (NE).  The ForCES working
   group is defining a protocol to allow a Control Element (CE) to
   control the behavior of a Forwarding Element (FE).

Table of Contents

   1.  Requirements notation  . . . . . . . . . . . . . . . . . . . .  3
   2.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Design of the  ForCES MIB Definition  . . . . . . . . . . . . . . . . . . . .  3
   4.  Association State  . . . . .  Associations kept in the MIB . . . . . . . . . . . . . . . . .  3 11
   5.  ForCES MIB Definition  . . . . .  Support for multiple CEs and FEs . . . . . . . . . . . . . . .  4 11
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 10 11
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11 12
   8.  Changes from Previous Draft Revisions  . . . . . . . . . . . . 11 12
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 13
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 12 13
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 12 14
   Appendix A.  Acknowledgments . . . . . . . . . . . . . . . . . . . 12 14
   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 13 14
   Intellectual Property and Copyright Statements . . . . . . . . . . 14 16

1.  Requirements notation

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  Introduction

   The ForCES MIB module is a primarily read-only MIB module that captures
   information related to the ForCES protocol ([RFC3654], [RFC3746], [forces-
   applicability-draft]
   [forces-applicability-draft] and [forces-protocol-draft]).

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   [RFC3410].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through the Simple Network Management Protocol (SNMP).
   Objects in the MIB are defined using the mechanisms defined in the
   Structure of Management Information (SMI).  This memo specifies a MIB
   module that is compliant to the SMIv2, which is described in STD 58,
   [RFC2578], STD 58, [RFC2579] and STD 58, [RFC2580].

   The ForCES MIB module does not include information that is specified
   in other MIBs, MIB modules, such as packet counters for interfaces, etc.

   More specifically, the information in the ForCES MIB module relative
   to associations that are up includes:

   o  identifiers of the elements in the association,

   o  configuration parameters of the association, and

   o  statistics of the association.

3.  Design of the  ForCES MIB

   In an NE composed of one or more FEs and a single CE, Definition

   The MIB module contains the CE is
   clearly aware of all associations and hence can provide this
   information in a single latest ForCES MIB.  In contrast, in an NE composed
   of more than one CE, such protocol version supported
   by the CE (forcesLatestProtocolVersionSupported).  Note that the CE
   must also allow interaction with FEs supporting earlier versions.

   For each association information is distributed identified by the pair CE ID and
   hence more than one ForCES MIB may be necessary, unless this FE ID, the
   following associated information is aggregated into a single ForCES MIB provided by some means
   beyond the scope MIB module as an
   entry (forcesAssociationEntry) in the association table
   (forcesAssociationTable):

   o  Version number of this document.  Nevertheless, the ForCES MIB
   design is compatible with both protocol running in this association
      (forcesAssociationRunningProtocolVersion).

   o  Time when the single-CE and the multiple-CE
   case.

4.  Association State

   Only associations that are UP are shown in the MIB.  Associations
   enter association entered the UP state as soon as the CE has sent to the FE an
   Association Setup Response message containing a successful
   Association Setup Result.

   Associations are removed from the MIB as soon as they leave the UP
   state, i.e., if the CE has not received any message (Heartbeat or
   other protocol message) from the FE within a given time period or if
   an Association Teardown message has been sent by the CE.

5.  ForCES MIB Definition

   The MIB contains the latest ForCES protocol version supported by the
   CE.  Note that the CE must also allow interaction with FEs supporting
   earlier versions.

   For each association identified by the pair CE ID and FE ID, the
   following associated information is provided by the MIB:

   o  Version number of the ForCES protocol running in this association.

   o  Time when the association entered the UP state.
      (forcesAssociationTimeUp).

   o  Time when the association left the UP state. state
      (forcesAssociationTimeDown).  Note that this is only used for
      notification purposes as the association is removed from the MIB
      immediately after it leaves the UP state.

   o  Number of ForCES Heartbeat messages sent from the CE
      (forcesAssociationHBMsgSent) and received by the CE
      (forcesAssociationHBMsgReceived) since the association is UP.

   o  Number of other ForCES messages sent from the CE
      (forcesAssociationOtherMsgSent) and received by the CE
      (forcesAssociationOtherMsgReceived) since the association is UP.
      Only messages other than Heartbeat, Association Setup, Association
      Setup Response, and Association Teardown are counted.

   Finally, the MIB module defines the following notifications:

   o  Whenever an association enters the UP state, a notification
      (forcesAssociationEntryUp) is issued containing the version of the
      ForCES protocol running.  Note that as CE ID and FE ID are
      indexes, they appear in the OID of the ForCES-protocol running-version running-
      version object.

   o  Whenever an association leaves the UP state, a notification
      (forcesAssociationEntryDown) is issued containing all associated
      information for this association.  The reason is that the
      association and all its associated information will be removed
      from the MIB immediately after this notification has been issued.

      FORCES-MIB DEFINITIONS ::= BEGIN

      IMPORTS
          MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
            mib-2, Integer32, Counter32
            FROM SNMPv2-SMI

          TEXTUAL-CONVENTION, TimeStamp
            FROM SNMPv2-TC

          MODULE-COMPLIANCE, OBJECT-GROUP,
          NOTIFICATION-GROUP
            FROM SNMPv2-CONF;

      forcesMib MODULE-IDENTITY
          LAST-UPDATED "200607041200Z" "200607261200Z"  -- Jul 4, 26, 2006
          ORGANIZATION "Forwarding and Control Element Separation
                        (ForCES) Working Group"
          CONTACT-INFO
              "Robert Haas (rha@zurich.ibm.com), IBM"
          DESCRIPTION
              "This MIB module contains managed object definitions
               for the ForCES Protocol."
          REVISION "200607041200Z" "200607261200Z"  -- Jul 4, 26, 2006
          DESCRIPTION
            "Initial version, published as RFC yyyy."
 -- RFC Ed.: replace yyyy with actual RFC number & remove this note
          ::= { mib-2 XXX }
 -- RFC Ed.: replace XXX with IANA-assigned number & remove this note

 --****************************************************************

      forcesMibNotifications OBJECT IDENTIFIER ::= { forcesMib 0 }
      forcesMibObjects       OBJECT IDENTIFIER ::= { forcesMib 1 }
      forcesMibConformance   OBJECT IDENTIFIER ::= { forcesMib 2 }

      ForcesID ::= TEXTUAL-CONVENTION
          STATUS      current
          DESCRIPTION
              "The ForCES identifier is a four octet quantity."
          SYNTAX      OCTET STRING (SIZE (4))

      ForcesProtocolVersion ::= TEXTUAL-CONVENTION
          STATUS      current
          DESCRIPTION
              "ForCES protocol version number." number.
               The version numbers used are defined in the
               specifications of the respective protocol:
               1 - ForCESv1 [RFCzzzz]."
 -- RFC Ed.: replace zzzz with actual RFC number of ForCES protocol
 -- & remove this note

          SYNTAX      INTEGER      Integer32 (1..255)

-- Notifications

      forcesAssociationEntryUp NOTIFICATION-TYPE
         OBJECTS     {
            forcesAssociationRunningProtocolVersion
         }
         STATUS      current
         DESCRIPTION
              "This notification is generated when a
                   forcesAssociationEntry object is created." as soon
               as an association enters the UP state."
         ::= { forcesMibNotifications 1 }

       forcesAssociationEntryDown NOTIFICATION-TYPE
         OBJECTS     {
            forcesAssociationRunningProtocolVersion,
            forcesAssociationTimeUp,
            forcesAssociationTimeDown,
            forcesAssociationHBMsgSent,
            forcesAssociationHBMsgReceived,
            forcesAssociationOtherMsgSent,
            forcesAssociationOtherMsgReceived                }
         STATUS      current
         DESCRIPTION
              "This notification is generated when a
                   forcesAssociationEntry object is destroyed." as soon
               as an association leaves the UP state."
         ::= { forcesMibNotifications 2 }

-- Objects

      forcesLatestProtocolVersionSupported OBJECT-TYPE
          SYNTAX      ForcesProtocolVersion
          MAX-ACCESS  read-only
          STATUS      current
          DESCRIPTION
                 "The ForCES protocol version supported by the CE.
                  The current protocol version is 1.
                  Note that the CE must also allow interaction
                  with FEs supporting earlier versions."
          ::= { forcesMibObjects 1 }

      forcesAssociations OBJECT IDENTIFIER ::= { forcesMibObjects 2 }

      forcesAssociationTable OBJECT-TYPE
          SYNTAX SEQUENCE OF ForcesAssociationEntry
          MAX-ACCESS not-accessible
          STATUS current
          DESCRIPTION
                 "The (conceptual) table of associations."
          ::= { forcesAssociations 1 }

      forcesAssociationEntry OBJECT-TYPE
          SYNTAX ForcesAssociationEntry
          MAX-ACCESS not-accessible
          STATUS current
          DESCRIPTION
                 "A (conceptual) entry for one association."
          INDEX { forcesAssociationCEID, forcesAssociationFEID }
          ::= { forcesAssociationTable 1 }

      ForcesAssociationEntry ::= SEQUENCE {
              forcesAssociationCEID             ForcesID,
              forcesAssociationFEID             ForcesID,

              forcesAssociationRunningProtocolVersion
                                          ForcesProtocolVersion,

              forcesAssociationTimeUp           TimeStamp,
              forcesAssociationTimeDown         TimeStamp,

              forcesAssociationHBMsgSent        Counter32,
              forcesAssociationHBMsgReceived    Counter32,
              forcesAssociationOtherMsgSent     Counter32,
              forcesAssociationOtherMsgReceived Counter32     }

      forcesAssociationCEID OBJECT-TYPE
          SYNTAX ForcesID
          MAX-ACCESS not-accessible
          STATUS current
          DESCRIPTION
                 "The ForCES ID of the CE."
          ::= { forcesAssociationEntry 2 1 }

      forcesAssociationFEID OBJECT-TYPE
          SYNTAX ForcesID
          MAX-ACCESS not-accessible
          STATUS current
          DESCRIPTION
                 "The ForCES ID of the FE."
          ::= { forcesAssociationEntry 3 2 }

      forcesAssociationRunningProtocolVersion OBJECT-TYPE
          SYNTAX      ForcesProtocolVersion
          MAX-ACCESS  read-only
          STATUS      current
          DESCRIPTION
          "The current ForCES protocol version used in this
           association.
           The current protocol version is 1."
          ::= { forcesAssociationEntry 4 3 }
      forcesAssociationTimeUp OBJECT-TYPE
          SYNTAX TimeStamp
          MAX-ACCESS read-only
          STATUS current
          DESCRIPTION
                 "The value of sysUpTime at the time this
                  association entered the UP state.
                  If this association started prior to the last
                  initialization of the network subsystem, then
                  this object contains a zero value."
          ::= { forcesAssociationEntry 5 4 }

      forcesAssociationTimeDown OBJECT-TYPE
          SYNTAX TimeStamp
          MAX-ACCESS read-only
          STATUS current
          DESCRIPTION
                 "The value of sysUpTime at the time this
                  association left the UP state."
          ::= { forcesAssociationEntry 6 5 }

      forcesAssociationHBMsgSent OBJECT-TYPE
          SYNTAX Counter32
          MAX-ACCESS read-only
          STATUS current
          DESCRIPTION
                 "A counter of how many heartbeat messages have
                  have been sent by the CE on this association
                  since it is up.
                  If this association started prior to the last
                  initialization of the network subsystem, then
                  this object contains the value since the
                  initialization."
          ::= { forcesAssociationEntry 7} 6 }

      forcesAssociationHBMsgReceived OBJECT-TYPE
          SYNTAX Counter32
          MAX-ACCESS read-only
          STATUS current
          DESCRIPTION
                 "A counter of how many heartbeat messages
                  have been received by the CE on this association
                  since it is up.
                  If this association started prior to the last
                  initialization of the network subsystem, then
                  this object contains the value since the
                  initialization."
          ::= { forcesAssociationEntry 8} 7 }
      forcesAssociationOtherMsgSent OBJECT-TYPE
          SYNTAX Counter32
          MAX-ACCESS read-only
          STATUS current
          DESCRIPTION
                 "A counter of how many messages other than
                  heartbeat (i.e., config and query)
                  have been sent by the CE on this association
                  since it is up.
                  If this association started prior to the last
                  initialization of the network subsystem, then
                  this object contains the value since the
                  initialization."
          ::= { forcesAssociationEntry 9} 8 }

      forcesAssociationOtherMsgReceived OBJECT-TYPE
          SYNTAX Counter32
          MAX-ACCESS read-only
          STATUS current
          DESCRIPTION
                 "A counter of how many messages other than
                  heartbeat (i.e., config response, query response,
                  event notification, and packet redirect)
                  have been received by the CE on this association
                  since it is up.
                  If this association started prior to the last
                  initialization of the network subsystem, then
                  this object contains the value since the
                  initialization."
          ::= { forcesAssociationEntry 10} 9 }

-- Conformance

      forcesMibCompliances   OBJECT IDENTIFIER
                               ::= { forcesMibConformance 1 }
      forcesMibGroups        OBJECT IDENTIFIER
                               ::= { forcesMibConformance 2 }

-- Compliance statements

      forcesMibCompliance  MODULE-COMPLIANCE
          STATUS current
          DESCRIPTION
            "The compliance statement for routers running ForCES and
            implementing the ForCES MIB."
          MODULE  -- this module
            MANDATORY-GROUPS { forcesMibGroup, forcesNotificationGroup} forcesNotificationGroup }
            GROUP forcesStatsGroup
            DESCRIPTION
              "Implementation of this group is recommended."

          ::= { forcesMibCompliances 1 }

-- Units of conformance

      forcesNotificationGroup NOTIFICATION-GROUP
          NOTIFICATIONS { forcesAssociationEntryUp,
                          forcesAssociationEntryDown
                        }
          STATUS  current
          DESCRIPTION

            "A collection of notifications for signaling important
             ForCES events."
          ::= { forcesMibGroups 1 }

      forcesMibGroup OBJECT-GROUP
          OBJECTS { forcesLatestProtocolVersionSupported,
                    forcesAssociationRunningProtocolVersion
                  }
          STATUS  current
          DESCRIPTION
            "A collection of objects to support management of ForCES
             routers."
        ::= { forcesMibGroups 2 }

      forcesStatsGroup OBJECT-GROUP
          OBJECTS { forcesAssociationTimeUp,
                    forcesAssociationTimeDown,
                    forcesAssociationHBMsgSent,
                    forcesAssociationHBMsgReceived,
                    forcesAssociationOtherMsgSent,
                    forcesAssociationOtherMsgReceived
                  }
          STATUS  current
          DESCRIPTION
            "A collection of optional objects to provide extra
             information about the associations. There is no protocol
             reason to keep such information, but these objects can
             be very useful in debugging connectivity problems."
        ::= { forcesMibGroups 3 }

      END

6.  Security Considerations

   Some of

4.  Associations kept in the readable objects MIB

   Only associations that are UP are reflected in this MIB module may be considered
   sensitive or vulnerable in some network environment.

   SNMP versions prior to module.
   Associations enter the UP state as soon as the CE has sent to the FE
   an Association Setup Response message containing a successful
   Association Setup Result.

   Associations are removed from the MIB module as soon as they leave
   the UP state, i.e., if the CE has not received any message (Heartbeat
   or other protocol message) from the FE within a given time period or
   if an Association Teardown message has been sent by the CE.

5.  Support for multiple CEs and FEs

   An NE consists of one or more FEs and one or more CEs.  Where there
   is a single CE, that CE will have knowledge of all the associations
   in the NE and so can provide the information necessary to support the
   managed objects defined in this MIB module.  Where there is more than
   one CE, information about the associations may be distributed among
   the CEs.  Whether each CE implements the managed objects for the
   associations of which it is aware or whether the CEs cooperate to
   present the appearance of a single set of managed objects for all the
   associations in the NE is outside the scope of this document.

6.  Security Considerations

   Some of the readable objects in this MIB module may be considered
   sensitive or vulnerable in some network environment.

   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example by using IPSec),
   even then, there is no control as to who on the secure network is
   allowed to access and GET/SET (read/change/create/delete) the objects
   in this MIB module.

   It is RECOMMENDED that implementers consider the security features as
   provided by the SNMPv3 framework (see [RFC3410], section 8),
   including full support for the SNMPv3 cryptographic mechanisms (for
   authentication and privacy).

   Further, deployment of SNMP versions prior to SNMPv3 is NOT
   RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
   enable cryptographic security.  It is then a customer/operator
   responsibility to ensure that the SNMP entity giving access to an
   instance of this MIB module is properly configured to give access to
   the objects only to those principals (users) that have legitimate
   rights to indeed GET or SET (change/create/delete) them.

7.  IANA Considerations

   The MIB module in this document uses the following IANA-assigned
   OBJECT IDENTIFIER values recorded in the SMI Numbers registry:

         Descriptor        OBJECT IDENTIFIER value
         ----------        -----------------------

         forcesMIB         { mib-2 XXX }

   Editor's Note (to be removed prior to publication): the IANA will need is
   requested to assign a number value for "XXX" under the 'mib-2' subtree and
   to record the assignment in the SMI Numbers registry.  When the
   assignment has been made, the RFC Editor is asked to replace "XXX"
   (here and in the MIB module) with the assigned value and to remove
   this MIB. note.

8.  Changes from Previous Draft Revisions

   Editor's Note (to be removed prior to publication): Prior to RFC
   publication of this document, the RFC Editor is asked to remove this
   entire section titled "Changes from Previous Draft Versions".

   Changes from draft-ietf-forces-mib-03.  They are small fixes to the
   text and the MIB module:

   o  Added MIB boilerplate according to
      http://www.ops.ietf.org/mib-boilerplate.html

   o  Clarified terminology with respect to MIB module and MIB managed
      objects.

   o  Added RFC Editor note to indicate RFC number for version 1 of
      ForCES protocol under ForcesProtocolVersion.

   o  Renumbered elements in forcesAssociationEntry starting with 1.

   o  Changed ForcesProtocolVersion from INTEGER to Integer32.

   o  Added forcesLatestProtocolVersionSupported into the mandatory
      forcesMibGroups conformance group.

   o  Explicitely added the forcesStatsGroup to the forcesMibCompliance
      compliance statement as optional.

   o  Moved the MIB Definition section to the front.

   o  Rephrased IANA Considerations section according to RFC 4181
      Section 3.5.2.

   o  Added RFC Editor note to remove the "Changes from Previous Draft
      Revisions" section prior to publication.

   Changes from draft-ietf-forces-mib-02.  They are refinements of the
   MIB:
   MIB module:

   o  Changed forcesAssociationCEID and forcesAssociationFEID from read-
      only to not-accessible to conform with Section 7.7 in [RFC2578].

   o  Removed forcesAssociationCEID and forcesAssociationFEID from the
      notifications.  This information is conveyed in the OID anyway.

   o  Added MIB conformance information.

   Changes from draft-ietf-forces-mib-01.  The changes are in response
   to the Working Group Last Call:

   o  Addition of two traps/notifications to signal the associations
      that enter or leave the UP state.

   o  Suppression of the DOWN and ESTABLISHING states.  Only
      associations in the UP state are kept in the table.

   o  Split of the Message counters into Heartbeat and other messages.

   o  Addition of the current running version of ForCES protocol for
      each association in the UP state.

   o  Addition of the latest version of the ForCES protocol supported by
      the CE.

9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2578]  McCloghrie, K., Ed., Perkins, D., Ed., and J.

              Schoenwaelder, Ed., "Structure of Management Information
              Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

   [RFC3410]  Case, J., Mundy, R., Partain,

   [RFC2579]  McCloghrie, K., Ed., Perkins, D., Ed., and B. Stewart,
              "Introduction J.
              Schoenwaelder, Ed., "Textual Conventions for SMIv2",
              STD 58, RFC 2579, April 1999.

   [RFC2580]  McCloghrie, K., Perkins, D., and Applicability J. Schoenwaelder,
              "Conformance Statements for Internet-
              Standard Management Framework", SMIv2", STD 58, RFC 3410, December 2002. 2580,
              April 1999.

   [RFC3654]  Khosravi, H. and T. Anderson, "Requirements for Separation
              of IP Control and Forwarding", RFC 3654, November 2003.

   [RFC3746]  Yang, L., Dantu, R., Anderson, T., and R. Gopal,
              "Forwarding and Control Element Separation (ForCES)
              Framework", RFC 3746, April 2004.

   [forces-protocol-draft]
              Doria, A., Haas, R., Hadi Salim, J., Khosravi, H., and W.
              Wang, "ForCES Protocol Specification", ID Document:
              draft-ietf-forces-protocol-08.txt, March 2006.

9.2.  Informative References

   [RFC3410]  Case, J., Mundy, R., Partain, D., and B. Stewart,
              "Introduction and Applicability Statements for Internet-
              Standard Management Framework", RFC 3410, December 2002.

   [forces-applicability-draft]
              Crouch, A., Khosravi, H., Handley, M., and A. Doria,
              "ForCES Applicability Statement", ID Document:
              draft-ietf-forces-applicability-04.txt, February 2006.

Appendix A.  Acknowledgments

   The author gratefully acknowledges the contributions of: Jinrong
   Fenggen, Xiaoyi Guo, Joel Halpern, Tom Petch, and Jamal Hadi Salim.

Author's Address

   Robert Haas
   IBM
   Saeumerstrasse 4
   Rueschlikon  8803
   CH

   Email: rha@zurich.ibm.com
   URI:   http://www.zurich.ibm.com/~rha

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   ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
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   INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
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