Generation Network Table 2.1 Comparing the Generalized SDP Architecture and Our Proposed SDP Framework Generalized SDP SDP Framework Criteria Architecture (Figure 2.2) (Figure 2.4) Customer platform Not catered for. Assumes Explicitly caters for customers access services customer access and via multiple layers and management since a platforms customer domain is defined. Also all GSOAs extend enablers into this domain Mapping of APIs Multiple APIs can be used GSOAs can be (implementing across multiple layers and implemented using reference points) platforms. This leads to standard-based APIs diverse and inconsistent consistently across specific implementations layers and domains. GSOAs remove ambiguity when mapping APIs Distributed Not catered for, but by its Each GSOA design pattern environment nature the SDP is a provides a middleware distributed system plane to manage distribution transparency Technology neutral Aims to be agnostic by GSOAs are technology generalizing vendor and implementation products which can make neutral. These properties implementation difficult are inherited by the SDP when using standards- framework based technologies Abstraction and Medium level of High level of abstraction lease of abstraction since the achieved using GSOAs. decomposition architecture abstracts only Each GSOA is easily vendor products. The decomposed when a model does not standard technology is decompose smoothly to chosen to implement the ease implementation service enablers, their APIs and the middleware plane The service functions provided by the IMS include the Call Session Control Functions (CSCFs) and Home Subscriber Server (HSS). The IMS also provides end-user, media processing, and OSS/BSS service functions, such as the SIP user equipment (UE), Media Resource Function Controller (MRFC) and Charging/ Event Collection Function (CCF/ECF), respectively. The IMS service functions End-user Service subscriber Service platform Enterprise Client IPTV IPTV service IPTV provider Media provider applications provider applic