Managed Object Instance

Description

A Managed Object Instance (MOI) is a concrete representation of a physical or logical network resource within a management system, structured according to a defined information model. Each MOI is an instantiation of a Managed Object (MO) class, which is a template defining the attributes, notifications, and operations applicable to that type of resource. For example, the MO Class "ManagedElement" might define attributes like "userLabel," "vendorName," and "locationName." A specific MOI of this class would represent an actual network element, such as "eNodeB-12345" in London, with specific values assigned to those attributes.

MOIs are organized in a Management Information Tree (MIT), a hierarchical namespace where each MOI is uniquely identified by its Distinguished Name (DN). The DN is composed of the Relative Distinguished Names (RDNs) of itself and all its ancestor MOIs in the tree. This structure reflects containment relationships; for instance, an MOI representing a cellular sector might be a child of an MOI representing a cell, which is a child of an MOI representing a base station. This hierarchy allows for efficient, scoped management operations. MOIs communicate with the management system (Network Manager, NM, or Element Manager, EM) via standardized interfaces, primarily the Itf-N (based on CORBA/XML) in earlier releases and the RESTful 3GPP Management Services (MnS) in 5G.

The lifecycle of an MOI involves creation, configuration, monitoring, and deletion. Operations on an MOI include GET (retrieve attribute values), SET (modify configuration), CREATE, DELETE, and ACTION (invoke a specific procedure). MOIs also generate notifications (asynchronous alarms or state change reports) to alert the management system of events. Key components of the MOI concept are the Information Model (e.g., 3GPP NRM - Network Resource Model), the naming and addressing scheme (DN/RDN), and the protocol bindings for northbound interfaces. In 5G, MOIs are central to the Service-Based Management Architecture (SBMA), where Managed Object Instances are exposed as manageable resources through producer-consumer relationships using HTTP/JSON.

Purpose & Motivation

MOIs exist to provide a standardized, abstracted, and programmatic way to manage the myriad of heterogeneous network elements in a multi-vendor telecommunications environment. Before such standardized information models, each vendor used proprietary management interfaces and data models, making integrated network management, automated provisioning, and multi-vendor interoperability extremely complex and costly for operators. The MOI concept, as part of a larger Managed Object framework, solves this by defining a common language and structure for representing network resources.

The primary problem addressed is the complexity of network management integration. By defining resources as MOIs with standardized attributes and behaviors, management systems can discover, configure, and monitor equipment from different vendors using the same set of operations. This enables unified fault, configuration, accounting, performance, and security (FCAPS) management. It also facilitates automated network lifecycle management, which is essential for modern concepts like network slicing and zero-touch network and service management (ZSM).

Historically, management interfaces were often command-line based and vendor-specific. The move towards object-oriented management models, influenced by the Telecommunications Management Network (TMN) framework and later the 3GPP Network Management (NM) work, established the Managed Object as a key principle. The instantiation of these objects as MOIs provided the concrete "handles" for management software. Its evolution through 3GPP releases has been towards greater alignment with IT practices (like RESTful APIs and YANG data models in later 5G management), but the core concept of an MOI as an instance of a modeled resource remains the foundational data entity for all management interactions.