Làm thế nào là ATM Thay đổi Chương này thảo luận về sự tiến hóa của khái niệm ATM. Thông báo đặc biệt được trao cho các giao diện vật lý, QoS loại và sự tiến hóa của phương pháp ATM và IP ảnh hưởng lẫn nhau. Chương này giúp hiểu được ý nghĩa của những thay đổi căn bản diễn ra tại thị trường toàn cầu ngày nay. Một số xu hướng trong tương lai cho sự tiến hóa ATM cũng được trình bày. ATM đã phát triển qua một số năm phản ánh những thay đổi trong công nghệ. | Chapter 7 How is ATM Changing This chapter discusses the evolution of ATM concepts. A special notice is given to physical interfaces QoS categories and evolution of methods for ATM and IP interworking. The chapter helps to understand the implications of radical changes that take place at the global market nowadays. Some future trends for ATM evolution are also presented. ATM has evolved over a number of years reflecting the changes in technologies and customer demands. This evolution involved the development of new concepts but it also complemented initial ideas. It is very difficult to briefly present all the changes that ATM observed within last 13 years. However it is possible to identify major categories in which the changes were the most significant Physical interfaces. With the time passing by a number of new interfaces have been standardized. The key factor was obviously the need for ensuring high scalability and flexibility of ATM solutions. The new interfaces were introduced along with technological achievements especially in the domain of optical transmission. Hence the transmission speed has evolved from 155 52 Mbps initially up to 1Gbps. At the same time with regards to market needs a number of low speed interface specifications were released. They include for instance transmission with the speed of 25 6 Mbps over UTP ATM over Fractional Links Inverse Multiplexing For ATM Frame-based ATM Interface. 113 ATM Basics Signaling and routing protocols. Initially ATM allowed only for the use of permanent virtual connections PVCs . With the introduction of UNI it became possible to establish switched connections VCs . This implied the need to define signaling protocols for the use within ATM networks. Hence the protocols such as IISP and next PNNI were designed. Finally to allow for network interworking there was a need for appropriate protocols such as BICI and AINI. Traffic management. This category covers all the QoS related issues. With the time passing
