ALITY OPTIMIZATION Capacity and Quality Principles In Part 5, "Capacity and Quality Principles," we bring expertise from mathematics, telephony, and other fields that we can apply to the design and modification of cellular systems. In Chap. 22, "Capacity and Quality Tradeoffs," we look at business and engineering tools that help us specify requirements, make decisions, and define problems. Then we look in greater depth at the process of creating mathematical models and performing quantifiable optimization of those models. The results of modeling and optimization can guide real-world design and implementation choices. Many of the models described in this chapter have been used in cellular design, in network design, and in the creation of modeling tools for cellular systems. In Chap. 23, "Traffic Engineering for Voice and Data," we provide a historical overview of the traffic engineering principles and models behind the public switched telephone network (PSTN) and then look at what happens to capacity when data services are added. We cover both circuit-switched and packet-switched networks. We then turn our attention to the mobile switching center (MSC). In Chap. 24, "Switching Capacity," we define the issues behind capacity calculations for the MSC switch main processor and other components. The next two chapters, "ANSI-41 Signaling Capacity" (Chap. 25), and "Capacity Calculations for Cellular Networks," (Chap. 26), provide the conceptual background for estimating capacity for the cellular signaling network, for every significant component of the cellular system, and for the network backhaul transport from base stations to MSC. In Chap. 27, "Conventional Reuse Principles," we look at the methods for optimizing the air interface of Advanced Mobile Phone Service (AMPS) and Global System for Mobility (GSM) networks. The last three chapters of Part 5 are dedicated specifically to code division multiple access (CDMA). In Chap. 28, "CDMA Principles for Downloaded from Digital Engineering Library @ McGraw-Hill (www.digit