Importance

Loading Importance Indicators...

Abstract

A system and method for controlling access to a shared channel for cell transmission in a shared medium network, wherein the shared medium distribution portion of said network extends from a node to a plurality of terminals within a community, having a tree-and-branch bus topology, has a downstream broadcast channel from said node to all terminals on said distribution network; a shared upstream channel from all of said terminals to said node; and a network controller at said node for central control of access of media transmissions from said terminals over said upstream channel. Media access control protocols reside in said controller and in said terminals. An asynchronous transmission mode (ATM) network element with said controller has ATM shared channel protocols to provide dynamic bandwidth allocation of said upstream channel. The system grants access to said shared upstream channel to any of said terminals utilizing a plurality of multiplexing modes of operation. A media access control cell with protocol control information is periodically inserted within broadcasts by said ATM network element on said downstream channel of said distribution portion of said network to said terminals, utilizing an ATM slotted transmission format, and dividing the channels into frames and time slots within frames. Access to said upstream shared channel is multiplexed, using a plurality of modes of operation. A reservation mode of operation provides a deterministic time reservation for time multiplexing access by a terminal for a specific number of time slots in a specific frame. A contention mode of operation provides random access to said upstream channel by any terminal during an identifiable frame. Said controller dynamically allocates such frames to each of said modes of operation.

Loading the Abstract Image...

First Claim