Element Manager

Description

The Element Manager (EM) is a fundamental component in the 3GPP Telecommunications Management Network (TMN) and later the Management and Orchestration (MANO) framework. It operates at the Element Management Layer (EML), sitting between the Network Element (NE) and the Network Management Layer (NML). Its primary function is to manage one or a group of NEs of the same type from a single vendor. The EM provides a northbound interface, typically based on standardized protocols like CORBA, SNMP, or more recently NETCONF/YANG, to communicate with higher-level Network Management Systems (NMS) or Operations Support Systems (OSS). Its southbound interface is often vendor-specific, using proprietary protocols or APIs to configure, monitor, and control the physical or virtual network elements.

Architecturally, the EM abstracts the complexities and vendor-specific details of the managed NEs, presenting a normalized, standardized view to the upper layers. This abstraction is crucial for multi-vendor network environments, allowing operators to integrate equipment from different suppliers into a unified management framework. The EM performs key FCAPS functions: it collects performance metrics and fault alarms from the NE, executes configuration changes (e.g., software updates, parameter tuning), manages security credentials, and may handle accounting data collection.

In modern networks, especially with the introduction of Network Function Virtualization (NFV), the role of the EM has evolved. It now also manages Virtualized Network Functions (VNFs), interacting with Virtualized Infrastructure Managers (VIMs) for resource allocation. The EM ensures the lifecycle management of its assigned network functions, from instantiation and configuration to scaling, updating, and termination. It acts as a crucial agent for closed-loop automation, receiving high-level service policies from the NMS and translating them into specific, executable commands for the underlying network resources.

Purpose & Motivation

The Element Manager was created to address the operational challenges arising from the proliferation of diverse and complex network equipment in telecommunications networks. Prior to standardized management frameworks, each vendor's equipment required its own proprietary management system, leading to operational silos, high integration costs, and inefficient manual processes for network operators managing multi-vendor environments.

The EM solves this by providing a standardized management abstraction layer. Its primary purpose is to isolate the network management systems from the heterogeneity of the underlying network elements. By handling vendor-specific communication and presenting a uniform interface upwards, it enables the creation of unified, integrated OSS. This reduces operational expenditure (OPEX) by allowing operators to use common procedures and systems for monitoring and configuring equipment from different suppliers. Furthermore, it facilitates automated operations and service assurance by being the point where abstract service-level intents are decomposed into concrete, element-level configurations.