绝大多数有线电视经营者目前需作出一项重要决定:对现有的有线设备是升级还是重建。这个决定要视以下几个因素来定: (1) 电缆的质量; (2) 有线设施是悬空或掩埋的地段; (3) 现有设备的带宽,有源及无源器件; The vast majority of cable operators currently have to make one important decision: whether to upgrade or rebuild an existing wired device. The decision depends on several factors: (1) the quality of the cable; (2) the location of the cable infrastructure that is vacant or buried; (3) the bandwidth of the existing equipment, both active and passive components;