ABSTRACT: This document introduces a layered architecture consisting of the Network Element Layer (NEL), the Element Management Layer (EML), the
Network Management Layer (NML), the Service Management Layer (SML), and the Business Management Layer (BML), and five Management
Functional Areas: Performance Management, Fault management, Configuration Management, Accounting Management, and Security Management.
This document, by describing functions, will provide a common frame of reference for discussion with potential application
developers of Telecommunications Management Network (TMN) applications. It is also intended to provide a functional description
foundation for the specification of interfaces between functions in the five TMN layers.