Internet发展的非常迅速。据统计,Internet上的主机数自1989年来大约每56个星期翻一番,同时在最近三年来Internet上WEB服务器的数量也至少是每23个星期翻一番。这种发展已开始严重危及到当前传统的、基于处理器设计的路由器。因为这种情况所引起的流量膨胀,以及新兴起的多媒体应用、视频会议等都需要大量的带宽。现在的交换技术可提供相当高可聚集的带宽,但只能提供一种桥接方法。 ATM(异步传输模式)的出现引起了人们的极大关注。ATM技术是一种快速的数据分组交换技术,它结合了电路交换和分组交换技术的优点,具有高容量、好的带宽伸缩性等特点,并且可以在一个单一的主体网络上携带多种信息媒体从而进行多种通信业务。然而,在大量的互连网和Internet上都使用的是IP协议,所以许多网络设备生产商都致力于通过将IP的网络路由能力与ATM的交换能力捆绑起来,以使网络既具有ATM的高性能,又具有IP的可伸缩性。但 Internet development is very rapid. According to statistics, the number of hosts on the Internet has doubled every 56 weeks since 1989, and the number of WEB servers on the Internet has also doubled at least every 23 weeks in the recent three years. This development has begun to seriously endanger the current traditional processor-based design of the router. Because of this situation caused by the expansion of traffic, as well as the emerging multimedia applications, video conferencing, etc. require a lot of bandwidth. Today’s switching technologies provide fairly high aggregate bandwidth, but only one bridging method. The emergence of ATM (Asynchronous Transfer Mode) has caused great concern. ATM technology is a fast data packet switching technology, which combines the advantages of circuit switching and packet switching technology, with high capacity, good bandwidth scalability and other characteristics, and can carry a variety of information media on a single host network Thus carry on many kinds of communication business. However, the IP protocol is used on a large number of Internet and Internet, so many network equipment manufacturers are committed to the network through the IP network routing capabilities and ATM switching ability to bundle, so that the network has both the high performance of ATM With IP scalability. but