However, the bandwidth is shared by all users on a particular cable segment. Because cable networks use a bus topology, every cable modem in a neighborhood shares access to a single coaxial cable backbone. The more subscribers in that area, the less bandwidth available to each. Thus the slower the connection rate and the more difficult it may become to establish a connection. Another concern is that if the CATV is damaged, this could bring down all of the users on that line.
Cable modems provide a dedicated service over a shared media.
ISDN typically provides digital service in increments of 64Kbps channels with a maximum of 128Kbps. ISDN requires adapters at both ends of the transmission so your access provider also needs an ISDN adapter. ISDN requires the phone company to install services within their phone switches to support this digitally switched connection service. DSL uses the existing ordinary copper telephone wiring to provide next generation high bandwidth services to the home and businesses. DSL technologies offer a wider range of frequencies over the cable than traditional telephone services which in turn allow for greater bandwidth with which to send and receive information.