Mobile and Multicast IP Services in PACS: System Architecture, Prototype, and Performance

Traditionally, wireless cellular communication systems have been engineered for voice. With the explosive growth of Internet applications and users, there is an increasing demand on providing Internet services to mobile users based on the voice-oriented cellular networks. However, Internet services add a set of radically diierent requirements on to the cellular wireless networks, because the nature of communication is very diierent from voice. It is a challenge to develop adequate network architecture and necessary systems components to meet those requirements. This paper describes our experience on developing Internet services, in particular , mobile and multicast IP services, in PACS (Personal Access Communication Systems). Our major contributions are ve-fold: (i) PACS system architecture that provides wireless Internet and Intranet access by augmenting the voice network with IP routers and backbone links to connect to the Internet; (ii) Simpliied design of RPCU (Radio Port Controller Unit) for easy service maintenance and migration to future IP standards such as IPv6; (iii) Native PACS multicast to eeciently support dynamic IP multicast and MBone connectivity; (iv) Optimization and incorporation of Mobile IP into PACS hand-oo mechanism to eeciently support roaming within a PACS network as well as global mobility between PACS networks and the Inter-net; (v) Successful prototype design of the new architecture and services veriied by extensive performance measurements of IP applications. Our design experience and measurement results demonstrate that it is highly feasible to seamlessly integrate the PACS networks into the Internet with global IP mobility and IP multicast services.