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一、网络发展的必然趋势众所周知,电话网是先於计算机网络而存在的。因而,计算机网络专家和有关厂商一直十分重视并尝试利用电话网所用的介质——双绞线来进行计算机数据通信,从而出现了许多象PLAN,OMinet,Token—Ring等以双绞线为介质的局部网,当然,有些网络,如PLAN,OMinet,限於当时的环境,因其性能不尽人意而被淘汰。而Token—Ring也由於其硬件产品,如网卡等价格比较昂贵,而没有象使用冈轴电缆的以太网那么流行,但毫无疑问,以双绞线为通信介质进行数据通信仍然是网络发展的必然趋势,并且很快就会成为现实。道理很简单,今天的软硬件技术已非昔日所能比拟,完全有可能制造出性能甚至比同轴电缆网还好的双绞线网。集数据通信和话音通信为一体的综合业务数据网的出现及其迅猛发展就是例证。
First, the inevitable trend of the development of the network As we all know, the telephone network is prior to the existence of the computer network. Therefore, computer network experts and related manufacturers have always attached great importance to and try to use the media used in the telephone network - twisted pair for computer data communications, resulting in many as PLAN, OMinet, Token-Ring twisted pair as a medium Local networks, of course, some networks, such as PLAN, OMinet, limited to the current environment, because of its performance is unsatisfactory and be eliminated. While Token-Ring is also more expensive due to its hardware offerings, such as network cards, and is not as popular as Ethernet using gang-axis cables, there is no doubt that data communication using twisted-pair cable as a communications medium is still a network development Inevitable trend, and will soon become a reality. The reason is very simple, today’s hardware and software technology is no match for the past, it is entirely possible to create a performance even better than the coaxial cable network twisted pair. The emergence of an integrated service data network integrating data communications and voice communications and its rapid growth are examples.