Studies of ATM Switches of support multicast communication for multiple prioritized media

支持宽带ISDN的异步传输模式（ATM）交换机近年来得到了广泛的研究。为了有效地传输多媒体业务，减少ATM交换机的等待时间和小区丢失概率是非常重要的。特别是语音、数据和图像等媒体对等待时延的QoS要求不同，因此需要能够支持多优先级业务的ATM交换机。此外，ATM交换机还需要支持多播流量，从而可以提供电话会议和视频点播。因此，能够处理多媒体流量并满足每种媒体的QoS的网络结构和网络控制策略对ATM交换机的性能有很大影响。在传统的研究中，没有对支持多优先介质的开关性能进行分析。在本研究中，我们提出了基于Bacher网络的多类淘汰赛分组交换机，并针对多播流量提出了横杆式ATM交换机和带部分缓冲区的多级ATM交换机。通过性能分析和计算机仿真，详细研究了蜂窝丢失概率和等待时延等基本性能指标。在此基础上，提出了能够有效处理多媒体流量并满足媒体QoS要求的网络结构和网络控制策略。期望我们所提出的交换机能够使多媒体通信网络更加高效。

The asynchronous transfer mode (ATM) switches to support Broadband ISDN have been widely studied in recent years. In order to transmit multimedia traffic efficiently, it is significant to reduce waiting time and cell loss probability in the ATM switch. Especially, the media such as voice, data and image has different request for quality of service (QoS) for waiting delay, so we need the ATM switch which can support the traffic with multiple priority classes. Also, the ATM switch is required to support a multicast traffic, which can provide teleconferencing and video on demand. Therefore, network structure and network control policy, which can treat multimedia traffic and satisfy QoS of each media, have a great effect for the performance of ATM switches. In the conventional research, performance of a switch which can support the media with multiple priorities has not been analyzed. In this research, we propose the knockout packet switch with Bacher network for multiple classes, and propose the crossbar ATM switch and the multistage ATM switch with partially buffers for multicast traffic. By performance analysis and computer simulations, we investigate basic performance measure such as cell loss probability and waiting delay in detail. As a result, we show network structure and network control policy, which can treat multimedia traffic efficiently and satisfy QoS of the media. It is expected that our proposed switches can make multimedia communication networks more efficient.