Abstract: CS2 functional model supporting FPLMTS in present ITU recommendation was first described. Considering the character of present and future network, we point outthe present model's disadvantage and propose an improved CS2 functional model, which separates terminal authentication and location register from SCF and introduces two new functional entities called LRF and TAF. In the end, the advantage and disadvantage of this new model was given.

Key words: intelligent networks, network interconnection, FPLMTS