The term TMN is introduced by the ITU-T (the former CCITT) as an abbreviation for `Telecommunications Management Network'. The concept of a TMN is defined by Recommendation M.3010 . TMN has a strong relationship with OSI management , and defines a number of concepts that have relevance for Internet Management .
According to M.3010, "a TMN is conceptually a separate network that interfaces a telecommunications network at several different points". The relationship between a TMN and the telecommunication network that is managed, is shown in Figure 1. According to this figure, the interface points between the TMN and the telecommunication network are formed by Exchanges and Transmission systems . For the purpose of management, these Exchanges and Transmission systems are connected via a Data Communication Network to one or more Operations Systems . The Operations Systems perform most of the management functions; these functions may be carried out by human operators but also automatically. It is possible that a single management function will be performed by multiple Operations Systems. In this case, the Data Communication Network is used to exchange management information between the Operation Systems. The Data Communication Network is also used to connect Work Stations , which allow operators to interpret management information. Work Stations have man-machine interfaces, the definition of such interfaces fall outside the scope of TMN (Work Stations are therefore drawn at the border of the TMN).
Recommendation M.3010 defines the general TMN management concepts and introduces several management architectures at different levels of abstraction: