The changes that have occurred in the telecommunications market in the last decade, and the transition to NGN networks that is currently happening have increased competitiveness in the telecommunication market and forced all the operators to optimize their costs and make their services much more attractive to end customers. However, this optimization can not be achieved using the previous generation of OSS systems. The move from traditional architecture to a next-generation telecommunications network poses additional problems for network management and operation. The introduction of multi-layer network architecture simplifies the development and introduction of advanced services, e.g. providing connectivity as a network layer service as in IMS, but hides the complex relationship between the services provided and the network resources used. In other words, Next Generation Networks require Next Generation Service Assurance to fully protect the services delivered to the customer and conserve operator revenues.

In the traditional architecture, the services provided were embedded in the networking equipment. Analysis of the service state was easy and straightforward. In modern networks, however, services are no longer associated with a single device in the network. Instead, each service is composed from resources provided by many devices operating within the network, or even based on many other simpler services offered by third party companies. With more advanced services offered, the structure of these services can become more and more complicated. In the case of any failure in such a complex mesh of connected resources, the contents, suppliers, quantity and importance of the affected services usually determines the severity of the network failure. Therefore, in a next generation network, exact information about the service state is essential for network management and operation.