Patent ID: 6028860
Filing Date: 2000-02-22
Classification: H04L,H04Q

Abstract:
A cable network comprising:one or more cables for conveying radio frequency signals;a plurality of cable modems coupled to the plurality of cables, wherein the cable modems accept data packets, convert the packet data into asynchronous transfer mode cells which are transmitted by radio frequency over the cables;a headend controller coupled to the cables for accepting the radio frequency signals transmitted by the plurality of cable modems and wherein the headend controller sends one or more radio frequency signals containing asynchronous transfer mode cells over the cables to the plurality of cable modems according to virtual connection information assigned to individual cells;a network interface coupled to the headend controller for inputting packet data to the headend controller and receiving packet data from the headend controller;a converter coupled to the headend controller which converts packet data from the network interface into asynchronous transfer mode cells for transmission by the headend controller to the plurality of cable modems and also converts asynchronous transfer mode cells generated by the cable modems and received by the headend controller into packet data for output by the network interface, wherein the asynchronous transfer mode cells contain video, audio or textual information such that cells are prioritized in order for transmission according to each individual cell's delay sensitivity;a shared media which is used to establish a downstream channel from the headend controller to the plurality of cable modems and to establish a plurality of upstream channels from the plurality of cable modems to the headend controller;a contention resolution circuit within the headend controller for resolving contentions which may arise according to a directed exponential backoff scheme with implicit feedback.