Toward a full implementation of SCIM functional block in IMS framework

IMS has been widely recognized as the control and brokering framework for delivering of the blended communication and multimedia services to the fix and mobile IP users. However, until recently, most of IMS services have been developed and deployed in a manner that does not carefully consider how these services can be combined and interact with each other in a beneficial way. Services can often overlap in terms of the logic that they execute, causing of redundant code across several application servers. Nowadays researching and industrial communities are approaching an IN-styled strategy of breaking down services into the basic building blocks needed to construct them known as Service Capabilities (SC). This breakdown is only possible if a full-functioning SCIM block is to be implemented. The SCIM will grant and schedule the user application to access those SCs properly, as well as resolve any rising conflict during that Service Capabilities access process. However at the moment there are no detailed specifications of this SCIM block from standardization bodies but only suggestions from research community to either put SCIM functions on Application platform or integrate it into the Service Invocation mechanisms of S-CSCF. But both of these approaches expose many disadvantages, either overloading S-CSCF or preventing the combination of services from different (Application) Platforms. In this paper, we propose a possible design that positioning the SCIM as an independent block between S-CSCF and Application Platforms. Finally a reference implementation at our Test-bed, which extended and re-used the existing IMS protocols and standard interfaces, is presented and early results are discussed.