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ISO/IEC 10742:1994/Amd 2:1999 – Elements of OSI Network Layer Management Information
Scope, Technical Updates, and Compliance Considerations for Amendment 2 to IEC 10742-94
The ISO/IEC 10742 standard, originally published as IEC 10742‑94, defines the management information elements required for the administration of the OSI Network Layer. As part of the OSI management framework established by ISO/IEC 7498‑4, this standard provides GDMO (Guidelines for the Definition of Managed Objects) templates and ASN.1 definitions for network‑layer managed objects. Amendment 2:1999 introduced essential modifications and additions to support evolving routing protocols, correct containment relationships, and improve interoperability with other management domains. This article examines the scope, technical requirements, implementation impact, and compliance notes for the standard and its second amendment.
1. Scope and Objectives
ISO/IEC 10742:1994 identifies the managed objects necessary for monitoring, controlling, and coordinating the OSI Network Layer protocol machine. It covers entities such as network entities, network service access points (NSAPs), network protocol machines (NPMs), and routing objects. The scope includes:
- Definition of managed object classes using GDMO notation
- Specification of attributes, actions, notifications, and packages
- Containment hierarchy for object registration and naming
- Mapping to OSI Systems Management (ISO/IEC 7498‑4)
Amendment 2:1999 (Amd 2) refines these definitions based on experience gained from early implementations and the emergence of new routing protocols such as IS‑IS and ES‑IS enhancements.
Key Objective: Amendment 2 ensures that the management information model for the Network Layer remains consistent with ISO/IEC 10589 (IS‑IS routing protocol) and ISO/IEC 9542 (ES‑IS routing protocol) updates.
2. Technical Requirements and Structure
The standard adopts a modular management approach using packages that group related attributes, notifications, and actions. Each managed object class is defined with a mandatory package plus several conditional packages that are instantiated based on the underlying protocol capabilities.
2.1 Managed Object Classes
The core classes defined in ISO/IEC 10742 include:
- networkEntity – represents a network layer entity
- networkServiceAccessPoint – represents an NSAP
- networkProtocolMachine – represents the state machine of a network protocol
- route – represents a routing table entry
| Object Class | Mandatory Package | Changes by Amd 2 |
|---|---|---|
| networkEntity | entityPackage | Added isisRoutingPackage and esIsSupportPackage |
| networkServiceAccessPoint | nsapPackage | Clarified containment and added nsapAddressAttribute naming |
| networkProtocolMachine | npmPackage | Introduced npmStatePackage for operational state |
| route | routePackage | No new packages, but attribute types updated |
2.2 Attributes and Notifications
Amendment 2 revised several attribute syntax definitions to align with the more recent version of ASN.1 (1998) and added new notifications for routing changes.
| Attribute | ASN.1 Type | Description |
|---|---|---|
| networkEntityTitle | OCTET STRING (SIZE(0..16)) | Title of the network entity (NSAP‑like format) |
| npmID | INTEGER | Unique identifier of the NPM |
| isisRoutingInstance | OCTET STRING | Identifies the IS‑IS routing instance (added in Amd 2) |
| portAddress | OCTET STRING | Subnetwork point of attachment (revised syntax) |
Implementation Tip: When building management agents, ensure your ASN.1 compiler supports the 1998 ASN.1 extensions for constrained types and simple table constraints as used in Amendment 2.
3. Implementation Highlights from Amendment 2
Amendment 2 does not introduce new object classes but significantly refines existing definitions. Key implementation impacts include:
- Containment hierarchy update: The containment rule now allows
networkProtocolMachineto be contained under eithernetworkEntityor a system object, providing flexibility for stack implementations. - State management: The new
npmStatePackageadds an operational state attribute based on the ISO/IEC 10164‑2 state model, enabling standardised fault reporting. - Routing packages: The
isisRoutingPackageandesIsSupportPackageinclude attributes for routing protocol version, hello timer values, and neighbour adjacency states. - Corrections to abstract syntax: Several ASN.1 types (e.g.
SecurityParameters) were corrected to match the final text of X.731.
Important: The rename of the
npmState attribute to operationalState in Amd 2 may break backward compatibility with older management applications. Implementers should support both names during a transition period. 4. Compliance and Certification Notes
Conformance to ISO/IEC 10742 is typically claimed as part of a larger OSI management product certification. The following points are crucial for compliance:
- GDMO registration: All object classes and packages must be registered according to the ASN.1 object identifier tree specified in the amendment.
- Test suites: Testing should verify that the containment relationships follow the updated rules (e.g. distinguishing between CLNP and IS‑IS contexts).
- Interoperability: Products claiming compliance with Amendment 2 must interoperate with implementations of ISO/IEC 10589 and ISO/IEC 9542 management extensions.
- Documentation: Management Information Base (MIB) documentation should reference the exact GDMO template definitions from Amd 2 to avoid ambiguity.
Caution: OSI management systems that ignore the containment corrections in Amendment 2 may generate inconsistent naming trees, leading to communication failures with simple network management protocol (SNMP) proxy agents that translate between GDMO and SNMP.
For certification, laboratories often require the implementation to pass the ISO/IEC 10742 reference test suites that cover the package selection rules updated in Amendment 2. Products that implement the full set of mandatory and conditional packages for network layer management are considered fully compliant.
Frequently Asked Questions
Q: What is the primary focus of ISO/IEC 10742?
A: It defines the management information elements – managed object classes, attributes, notifications, and actions – for controlling and monitoring the OSI Network Layer within a systems management environment.
A: It defines the management information elements – managed object classes, attributes, notifications, and actions – for controlling and monitoring the OSI Network Layer within a systems management environment.
Q: Does Amendment 2 introduce any new managed object classes?
A: No, Amendment 2 does not add new classes. Instead it updates packages, containment rules, and attribute definitions for the existing four classes (networkEntity, networkServiceAccessPoint, networkProtocolMachine, and route).
A: No, Amendment 2 does not add new classes. Instead it updates packages, containment rules, and attribute definitions for the existing four classes (networkEntity, networkServiceAccessPoint, networkProtocolMachine, and route).
Q: How does this standard relate to other OSI management standards?
A: It builds upon the generic managed objects of X.723 (ISO/IEC 10164‑2) and follows the GDMO methodology of X.722 (ISO/IEC 10165‑4). It also references the state management model of ISO/IEC 10164‑2 and the alert management of ISO/IEC 10164‑4.
A: It builds upon the generic managed objects of X.723 (ISO/IEC 10164‑2) and follows the GDMO methodology of X.722 (ISO/IEC 10165‑4). It also references the state management model of ISO/IEC 10164‑2 and the alert management of ISO/IEC 10164‑4.
Q: Is compliance with Amendment 2 mandatory for network management implementations?
A: For products claiming OSI network layer management conformance, compliance with the base standard and its amendments is strongly recommended to ensure interoperability with modern OSI stacks and routing protocols.
A: For products claiming OSI network layer management conformance, compliance with the base standard and its amendments is strongly recommended to ensure interoperability with modern OSI stacks and routing protocols.
Article prepared for technical documentation purposes — 2026