Element Manager

Description

An Element Manager (EM) is a management system component that provides a package of end-user functions for the management of a set of closely related types of network elements. It is a key element in the Telecommunications Management Network (TMN) architecture, specifically at the element management layer. The EM offers a user interface and a set of capabilities that allow operators to perform management tasks on network elements, such as configuration, fault management, performance monitoring, and security management. These functions can be divided into two main categories: those that are generic and apply to all element types, and those that are specific to the technology or vendor of the network elements.

The EM communicates with network elements through a management interface, often referred to as the Itf-N interface in 3GPP. This interface allows the EM to send commands and receive data from the elements. The EM itself may be integrated with a Network Management System (NMS) or operate as a standalone system. In 3GPP, the EM is responsible for managing a subset of network elements, typically of the same type, such as all eNodeBs in a region or all core network nodes of a certain vendor.

The functions provided by an EM include: fault management (alarm collection, correlation, and clearing), configuration management (provisioning, parameter setting), performance management (data collection, threshold monitoring), security management (access control, audit logs), and software management (upgrades, backups). These functions are exposed to the user through a graphical user interface or an API, enabling operators to efficiently manage the network.

The EM is closely related to Element Management Functions (EMF), which are the underlying capabilities that the EM implements. The EM provides the end-user functions, while the EMF are the specific operations that can be performed on individual elements. The EM may manage multiple network elements of the same type, and it abstracts the complexity of dealing with each element individually.

In modern networks, the EM is evolving to support cloud-native, virtualized network functions (VNFs) and containerized network functions (CNFs). It often integrates with orchestration and automation frameworks, such as ONAP or OSM, to enable end-to-end service management. The concept of the EM has been stable since Rel-4, but its implementation has adapted to new technologies, including model-driven management using YANG and NETCONF.

Overall, the Element Manager is a critical component for network operations, providing the tools and interfaces needed to manage network elements efficiently and reliably. It bridges the gap between the network elements and the higher-level management systems, ensuring that operators can maintain and optimize their networks.

Purpose & Motivation

The Element Manager exists to provide a dedicated management interface and toolset for a specific set of network elements. Before its standardization, each network element vendor provided its own proprietary management system, leading to fragmentation and high operational costs. The EM solves this by offering a standardized set of end-user functions that can manage multiple elements of the same type, regardless of vendor, as long as they comply with 3GPP specifications.

The motivation for the EM was to create a clear separation between element management and network management. The TMN architecture defines layers, and the EM operates at the element management layer, focusing on the individual elements. This allows the network management layer to focus on end-to-end network views and services, while the EM handles the details of element configuration and monitoring.

Historically, the EM concept was introduced in 3GPP Rel-4, alongside the definition of Element Management Functions. It has since been widely adopted in 3G, 4G, and 5G networks. The EM has evolved from a standalone, often proprietary system to a more open, standards-based component that can integrate with modern orchestration and automation platforms. Its role remains essential for ensuring that network elements are properly configured, monitored, and maintained.