RFC 1573 (rfc1573) - Page 3 of 55

Evolution of the Interfaces Group of MIB-II

RFC 1573               Interfaces Group Evolution           January 1994


2.1.  Object Definitions

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the subset of Abstract Syntax Notation One (ASN.1)
   defined in the SMI.  In particular, each object object type is named
   by an OBJECT IDENTIFIER, an administratively assigned name.  The
   object type together with an object instance serves to uniquely
   identify a specific instantiation of the object.  For human
   convenience, we often use a textual string, termed the descriptor, to
   refer to the object type.

3.  Experience with the Interfaces Group

   One of the strengths of internetwork-layer protocols such as IP [6]
   is that they are designed to run over any network interface.  In
   achieving this, IP considers any and all protocols it runs over as a
   single "network interface" layer.  A similar view is taken by other
   internetwork-layer protocols.  This concept is represented in MIB-II
   by the 'interfaces' group which defines a generic set of managed
   objects such that any network interface can be managed in an
   interface-independent manner through these managed objects.  The
   'interfaces' group provides the means for additional managed objects
   specific to particular types of network interface (e.g., a specific
   medium such as Ethernet) to be defined as extensions to the
   'interfaces' group for media-specific management.  Since the
   standardization of MIB-II, many such media-specific MIB modules have
   been defined.

   Experience in defining these media-specific MIB modules has shown
   that the model defined by MIB-II is too simplistic and/or static for
   some types of media-specific management.  As a result, some of these
   media-specific MIB modules have assumed an evolution or loosening of
   the model.  This memo is a proposal to document and standardize the
   evolution of the model and to fill in the gaps caused by that
   evolution.

   A previous effort to extend the interfaces group resulted in the
   publication of RFC 1229 [7].  As part of defining the evolution of
   the interfaces group, this memo applies that evolution to, and
   thereby incorporates, the RFC 1229 extensions.

3.1.  Areas of Clarification/Revision

   There are several areas for which experience indicates that
   clarification, revision, or extension of the model would be helpful.
   The next sections discuss these.




McCloghrie & Kastenholz