Research On NGN Service Control Capability

The Next Generation Network (NGN) is the evolving goal of telecommunication networks. But the knowledge about the extent and limitation of NGN service control capabilities remains absent. The extent of NGN service control capabilities exhibits the advantage of NGN while the limitation illuminates the evolving path of NGN. Softswitch is the core entity of NGN control layer which determines the extent and manner of NGN service control capabilities that the services can utilize. Within this background, this dissertation makes an in-depth and systematic research on NGN service control capabilities. And the main contributions are as follows:1. Based on contrast analysis of the legacy telecom network and NGN, this dissertation proposes that the numerical relationship of signalling link and media channel will be a new criterion on the service classification in NGN from service developer view. This new criterion is helpful for the creation of new service and can be well understood by service users and service providers.2. Based on the information operated, this dissertation divides NGN service control capabilities into four classes: call, bear, profile and message and puts forward the corpora of NGN service control capabilities. Each element of the corpora is prescribed in detail and the newly added service control capabilities in NGN are pointed out. Therefore comes to the conclusion that the service control capabilities of NGN are enlarged.3. An implementation and network platform independent model for service description is propoesed. It consists of four elements: EP (endpoint), LI (communication link), ELR (relations between endpoints and communication links) and LR (relations between communication links). EP and LI represent the static parts of a service which are described using object model. ELR and LR are presented through directed graphs which describe all possible behaviors of the service.4. In order to provide services to multiple standard interfaces, a novel Signalling and Bearer Separated Call Relation Model (SBS-CRM) of Softswitch and a General Service View (GSV) which based on SBS-CRM is proposed. Different interfaces can be adapted to GSV by adding a view translation layer between them.