Qsn: a model to the network-service interface

Transmission networks are mainly used to connect the switches of an operator. Only a few customers as banks, service providers, etc. required some services directly from the transmission network to connect the main sites they owned. Nowadays, the number and the variety of services (leased lines) has increased and the management requirements are changing everyday. Equipments which are supporting these services have a wide spectrum of providers with proprietary management solutions. Furthermore, the SDH transmission technology is now replacing the current PDH technology but they will have to coexist for a long time, allowing a leased line to be set up through different technologies. In order to meet these considerations, Telefonica has developed an information model for the interface between the TMN network and service layers. This model was developed for the SDH management system, but thinking of extending it to other OS´s at network level for interoperating with leased lines SOS. Telefonica information model was designed with two main objectives: to follow the current standards (Facto and jure) and to facilitate the extensibility to other transmission technologies,