Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
và để thay đổi trong môi trường vật lý xung quanh. Một mục tiêu quan trọng trong truyền thông di động là để khắc phục sự xuống cấp về chất lượng truyền thông gây ra bởi sự thay đổi kênh. Hình 3.2 minh họa việc tuyên truyền đa đường trong một môi trường di động. | 18 EVOLUTION OF MOBILE NETWORKS AND SERVICES also crucial technologies. The Ubiquitous Service Platform is a relatively complex concept and impacts many technology areas. For this reason an understanding of Chapters 2 6 7 9 and 12 is required in order to gain a full insight into this important XG component. We also consider the AAA and the Mobility support at sub-IP layers of RAN and in the service platform since those functionalities are realized by well-harmonized coordination of networks and terminals. This discussion also relates to the system security that comprises network security and terminal security. Chapter 10 addresses this important area. Any security solution must be scalable without practical limit and flexible but robust. Not only will terminal base be huge but terminal networking environments may be heterogeneous and rarely in a stable state. Multimedia traffic is increasing far more rapidly than speech and will increasingly dominate traffic flows. Since XG will effectively remove the limitations on bandwidth the network will provide the user with the ability to more efficiently discover and receive multimedia services including e-mail file transfers messaging and multimedia distribution services. These services can either be symmetrical or asymmetrical real time or not real time. They may consume data at rates requiring high bandwidths and low latency. With this forecast we identify application technologies for example media coding technology in addition to network and terminal technologies which are essential to foster new applications. These new multimedia technologies are discussed in Chapter 8. The following chapters cover and expand upon the essential technologies discussed in this chapter. It is our belief that these technologies developed and deployed as we describe in this book will result in a commercially viable and life-enhancing next-generation communication network. 2 The All-IP Next-generation Network Architecture Ravi Jain Muhammad
