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一、宽带业务的种类 接入网的业务正逐步由传统的窄带业务向宽带业务发展。讨论宽带业务实际上有两层含义:大于2Mbit/s的业务和分组化、IP化的业务。传统IP网上的业务有3项:E-mail、FTP和Telnet,但是这3项业务并没有促进IP网的大发展,在一段时间内网络与业务均处于缓慢增长的状态。20世纪90年代初,Web的出现,使IP网急剧地发展起来,原因是Web业务与IP网极其适配,也就是说IP网的不可管理性、不面向连接的特性以及尽力而为的数据传输特性和Web的自由链接特性(超级链)、不面向业务流及实时传输的特性是完全适配的。因而Web业务成了IP网的“杀手业务”,它促使IP网迅速发展起来,Web业务是IP网的主导业务。 因特同业务量的增长构成了数据业务的增长。除了用户数量的指数式增长外,业务带宽也呈现了指数式增长态势。例如在1990年左右,主要业务是E-mail,带宽仅1kbit/s左右;到了1995年,主要业务成为Web
First, the types of broadband services Access network business is gradually from the traditional narrowband business to broadband business development. Discussion Broadband services actually have two meanings: more than 2Mbit / s of business and packetization, IP-based business. Traditional IP network business has three: E-mail, FTP and Telnet, but these three business did not promote the development of IP networks, network and business are in a period of slow growth. The advent of the Web in the early 1990s led to the rapid development of IP networks due to the extreme adaptation of Web services to IP networks, that is, the unmanageability of IP networks, the lack of connection-oriented features and best-effort data Transmission characteristics and the Web’s free-link feature (hyperlink), non-business-oriented and real-time transmission features are fully adapted. As a result, the Web business has become a “killer business” of the IP network, which prompts the rapid development of the IP network. The Web business is the leading business of the IP network. The growth of Internet traffic constitutes the growth of data services. In addition to exponential growth in the number of users, business bandwidth also showed an exponential growth. For example, in about 1990, the main business is E-mail, the bandwidth is only about 1kbit / s; by 1995, the main business into the Web