Transport architecture for UMTS/IMT-2000 cellular networks

In this paper we discuss the transport architecture options for the UMTS/IMT-2000, or 3G (3rd Generation), cellular networks. The interfaces between access nodes in a cellular network and the changes incorporated to support packet data services are described. Challenges in selecting one transport technology over another are outlined with reasoning. Requirements to support mobile telephony as well as Internet services in a cellular network are explained. The new ATM standard, ATM Adaptation Layer type 2 (AAL2) and its applicability for transporting compressed speech in an ATM based cellular network is described. A similar approach in IF, multiplexing in Real-Time Transport Protocol (RTP) payload to transport compressed speech on selective interfaces of 3G network, is introduced. Transport network architecture evolution within four different scenarios is evaluated.