ATM Broadband Technology and Applications

Author: Quan Shouyi
Editor: Zhou Ming
Publisher:
Publish Date: 1998-10-01
Features: Summary This book introduces the birth of ATM, the basic composition and key technologies of ATM switches, ATM networking technologies, and their applications in multi-service platforms and integration with IP. It discusses in detail the characteristics and structure of ATM, numbering and signaling, ATM layering and classification control technologies, ATM network interconnection technologies with Frame Relay networks and N-ISDN, broadband data services based on ATM, the composition and application of video conferencing and video-on-demand. The book also discusses ATM and IP integration technologies such as LANE, IPOA, MPOA, IP switching, and tag switching. Finally, it introduces the development trends of broadband information networks, which are of the information superhighway.
Excerpt: After completing ISDN, to achieve true technology integration, research has been conducted on multiple switching technologies such as burst switching, multi-rate switching, and dynamic switching. However, due to their technical complexity, these were eventually abandoned. Among the numerous experiments, two approaches are worth mentioning because they incorporated the idea of ATM. In 1983, John Turner proposed a concept for a fast packet switch, which differed from traditional packet switches in the following ways: (a) replacing software routing with hardware self-routing; (b) using fixed-length packets instead of variable-length packets; (c) simplifying error control procedures, performing only error detection at intermediate nodes, discarding erroneous packets, and implementing error correction at the terminals. The fast packet switch not only achieved access speeds of hundreds of megabits per second but also had packet transmission and processing delays in the microsecond range, enabling real-time traffic switching. J. Turner implemented hardware self-routing using a Banyan network. Almost simultaneously, France's CENT proposed a so-called "Asynchronous Time Division (ATD)" switching structure. In ATD, the fixed-length packet information consists of a header and an information field. The header's functions are traffic control, routing control, and error correction. In ATD, packet information is stored in a common memory, and after the header is processed and switched, it is output along with the information from a designated port. The input and output port speeds of ATD switches also reached hundreds of megabits per second with minimal delay, enabling the integration of multiple services such as voice, images, and data. Due to their ability to rapidly switch voice, data, and image information in fixed-length packets with minimal delay, these switches made the integration of all services possible. Major companies worldwide, such as Bell Labs, Fujitsu, Hitachi, and British Telecom, successively researched and launched various types of switches. In 1989, the Eighteenth Study Group of the International Telegraph and Telephone Consultative Committee (CCITT) of the International Telecommunication Union (ITU), based on existing research results, proposed a new information transmission method—the Asynchronous Transfer Mode (ATM)—and designated ATM as a solution for implementing B-ISDN. From then on, ATM was officially born.