Abstract: The selection of which channel to use by a cable modem terminating system (CMTS) is made a function of input supplied by a spectrum analyzer. Note that typically the cable distribution system has coupled to it at the head end not only the CMTS but also a spectrum analyzer, which has been used in the prior art only for initial establishment and subsequent maintenance of the network, tasks which are performed manually by field technicians. In one embodiment of the invention an interface is established between the CMTS and the spectrum analyzer so that the CMTS and the spectrum analyzer can communicate with each other, and the decision on which channel to use for the upstream is made by the CMTS based at least in part on information provided by the spectrum analyzer. Alternatively, the CMTS and spectrum analyzer are each interfaced to a spectrum controller which makes the decision of which channel to use for the upstream based at least in part on information provided by the spectrum analyzer.

Abstract: Cable modems and CMTS modules, connected to a single cable so as to provide cable modem service to a respective set of the cable modems, are arranged so one of the CMTSs can backup the other. Each of the CMTSs simultaneously broadcasts its downstream channel on its own assigned one of the cable channels that is accessible by the cable modems for which it is assigned to provide the primary downstream channel, and each cable modem is assigned in addition to its primary downstream channel at least one alternative downstream channel which is supplied by a CMTS other than its primary CMTS, so that when the primary downstream channel of a cable modem becomes invalid the cable modem switches to the alternative downstream channel. When doing so, the cable modem employs many of the parameters that were established during the initialization it performed with the primary CMTS.