If too many people try to transmit information at the same time, lines can get clogged unless they are properly managed. With so many people sharing the same bandwidth, if the network's not managed well, you're going to have problems. Back when cable-TV companies supplied only cable TV, sophisticated network monitoring wasn't necessary. Customers couldn't really slow the system down because they were only receiving the signal, not sending it back. A channel would flicker, and our phones lit up.
Network management is a lot trickier in a high-speed environment.
TCI discovered that some customers were using the high-speed cable connections to support whole Internet sites, slowing down service across entire sections of the system. Unfortunately, somebody accidentally put a restriction on the amount of traffic that could be sent in the reverse direction, from the cable head-end to every customer on the system. A number of cable operators and customers complained that Excite At Home had fallen down on its high-speed promises. Anticipating capacity needs is a basic part of properly managing a network. On that point, he says, At Home simply didn't deliver.