Interoperability between UMTS and cdma2000 networks

In overlaying an existing cdma2000 network with a UMTS network, service transparency and number portability are important requirements for end users and hence the network operator. To support both requirements, one could introduce a protocol conversion node between the two networks; however, such a solution does not fully meet the requirements due to inherent technical constraints imposed by the differing standards. This article describes a network architecture based on the dual stack concept that satisfies the service transparency and number portability requirements across UMTS and cdma2000 networks, and also defines the functionality of the network nodes and the call processing procedures.