The Internet era started in 1969. A family tree of the Internet is shown in Figure 1.1. The key driver for the Internet protocol (IP)-based network is a common application and service environment across multiple types of net-works. In fact, the IP has created an open platform for innovative, flexible, and fast service creation, has enabled existing services to be supported, and has provided IP-based mobility for all types of wired and wireless transport in both the access network and the core network.
The target setting is to (1) create a world class all-IP system with rapid time-to-market and future-proof design, (2) enable flexibility for providing new, revolutionary services while ensuring smooth network evolution and service continuity, (3) provide access independent design for globally seam-less services, and (4) enable growth of revenue-generating systems now by leveraging the newly emerged wireless data market.
1.2 Wireless IP
The basic concept of wireless IP is shown in Figure 1.2. It is basically a pow-erful confluence of the network interworking layer and the tetherless con-nectivity with or without mobility in a heterogeneous networking environment with the promise of seamless connectivity across network sub-domains. Combining the best of both wireless and IP technologies has brought us into the era of wireless IP. Wireless IP will enable cost-effective, high-quality IP-based wireless multimedia services, including voice over IP, in large volumes [1–8].
In most developed markets the volume of data traffic has already sur-passed that of voice traffic, and this trend will only continue to accelerate.