计算机通信网络可以是终端、线路和计算机以数据收集、传输、处理和分配为目的的简单集合,也可以是具有数百个终端和多台计算机,跨越数千公里用通信线路联接在一起以共享资源为目的的复杂系统。虽然后者是人们追求的目标,但就国内目前经济和技术水平而言,尚无能力组成这样的网络,同时,最近国内基本建成或即将建成的网络也基本上属于面向终端的网络。鉴于这种情况,本文主要对面 A computer communication network may be a simple collection of terminals, lines, and computers for the purpose of data collection, transmission, processing, and distribution, or may have hundreds of terminals and multiple computers linked together by communication lines over thousands of kilometers Resources for the purpose of complex systems. Although the latter is the goal pursued by the people, it is incapable of forming such a network in terms of the current economic and technological level in the country. At the same time, the network basically completed or soon to be completed in China is basically a terminal-oriented network. In view of this situation, this article mainly opposite