近年来,随着计算机在各行各业的广泛应用,许多单位对数据传输的需求越来越多。如果各单位自行建网,不但会因重复工作而造成经济上的浪费,而且会加剧邮电部门的线路紧张状况。因此由邮电部门建立公共 In recent years, with the widespread use of computers in all walks of life, many organizations have an increasing demand for data transmission. If all units set up their own networks, not only would they be economically wasteful by duplicating work, but they would also aggravate the tension in the post and telecommunications departments. Therefore, public sector established by the post and telecommunications