Background: Know: ASN.1 Recognize:

Anticipates: CMIP, Netconf

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Macro for defining OBJECT-TYPE

SMI clauses
Conformance requirements

Structure of Management InformationEdit

  • SMI (Structure of Management Information) is a set of common structures and identification scheme used to define managed objects and their behaviour. These managed objects which represent resources of managed entites is defined by ASN.1} and stored in MIBs .

The SMI is divided into three parts: module definitions, object definitions, and, trap definitions.

(1) Module definitions are used when describing information modules. An ASN.1 macro, MODULE-IDENTITY, is used to concisely convey the semantics of an information module.

(2) Object definitions are used when describing managed objects. An ASN.1 macro, OBJECT-TYPE, is used to concisely convey the syntax and semantics of a managed object.

(3) Notification definitions are used when describing unsolicited transmissions of management information. An ASN.1 macro, NOTIFICATION-TYPE, is used to concisely convey the syntax and semantics of a notification.

  • There are several version of SMI:

SMI [ STD 16, RFC 1155&1212]
SMIv2 [STD 58, RFCs 2578-80]
SMIng discussion, e.g: RFC3780

  • Alternatives to SMI include:

(a) Managed Object Format (MOF) from {DMTF (Distributed Management Task Force):

MOF is a language used to define classes in [x {Common Information Model] - a model used to describe how to represent real-world managed objects. The MOF syntax is a way to describe object definition in textual form. The main component of a MOF specification are texual descriptions of element qualifier (meta-data about classes, properties, methods, etc.), comments and compiler directives, and the specific class and instance definitions. A MOF file can be encoded in either Unicode} or ETF-8}.


(b) Guidelines for the Definition of Managed Object [GDMO] for CMIP ( Common Management Information Protocol):

To develop management solutions using the Telecommunications Management Network framework and CMIP services, the management information base ( MIB} ) is described using a schema called GDMO, which is short for Guidelines for the Definition of Managed Objects.
GDMO, specified in ISO/IEC 10165} / ITU-T X.722},defines the management information transferred between computer systems that use the OSI protocol CMIP.


(c) XML Schema definitions:

- XML (Meta-Markup Language )produced by the {WorldWide Web Consortium (W3C) was first designed for document-focused but it is widely used for presentation of many data structure type. XML-based network management}, which applies XML to network management presents many advantages such as:

XML Schema defines the structure of management information in a flexible manner.
XML processes management data easily and generates HTML (HyperText Markup Language) documents for a variety of user interface views.

- Implementation of XML technology is increasingly important in network management. This mechanism is used in DSL Forum} and Netconf}

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