RFC 2737 (rfc2737) - Page 3 of 56

Entity MIB (Version 2)

RFC 2737                 Entity MIB (Version 2)            December 1999


   o  A set of fundamental applications described in RFC 2573 [RFC 2573]
      and the view-based access control mechanism described in RFC 2575
      [RFC 2575].

   A more detailed introduction to the current SNMP Management Framework
   can be found in RFC 2570 [RFC 2570].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the mechanisms defined in the SMI.

   This memo specifies a MIB module that is compliant to the SMIv2. A
   MIB conforming to the SMIv1 can be produced through the appropriate
   translations. The resulting translated MIB must be semantically
   equivalent, except where objects or events are omitted because no
   translation is possible (use of Counter64). Some machine readable
   information in SMIv2 will be converted into textual descriptions in
   SMIv1 during the translation process. However, this loss of machine
   readable information is not considered to change the semantics of the
   MIB.

2.  Overview

   There is a need for a standardized way of representing a single agent
   which supports multiple instances of one MIB.  This is presently true
   for at least 3 standard MIBs, and is likely to become true for more
   and more MIBs as time passes.  For example:

      - multiple instances of a bridge supported within a single device
        having a single agent;

      - multiple repeaters supported by a single agent;

      - multiple OSPF backbone areas, each one operating as part of its
        own Autonomous System, and each identified by the same area-id
        (e.g., 0.0.0.0), supported inside a single router with one
        agent.

   The fact that it is a single agent in each of these cases implies
   there is some relationship which binds all of these entities
   together.  Effectively, there is some "overall" physical entity which
   houses the sum of the things managed by that one agent, i.e., there
   are multiple "logical" entities within a single physical entity.
   Sometimes, the overall physical entity contains multiple (smaller)
   physical entities and each logical entity is associated with a
   particular physical entity.  Sometimes, the overall physical entity
   is a "compound" of multiple physical entities (e.g., a stack of
   stackable hubs).



McCloghrie & Bierman        Standards Track