System and method for controlling access to a shared channel for cell transmission in shared media networks

A system 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, comprising:

• 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;
• 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 residing in said controller and in said terminals;
• an asynchronous transmission mode (ATM) network element at said node having ATM shared channel protocols to provide dynamic bandwidth allocation of said Upstream channel;
• and
• means to grant access to said shared upstream channel to any of said terminals utilizing a plurality of multiplexing modes of operation;
• wherein said means to grant access to said shared upstream channel to any of said terminals utilizing a plurality of multiplexing modes of operation, comprises:
• a media access control cell with protocol control information periodically inserted within broadcasts by said ATM network element on said downstream channel of said distribution portion of said network to said terminals;
• said broadcasts on said downstream channel utilizing an ATM slotted transmission format;
• said media access control protocols dividing said downstream and upstream channels into frames and time slots within frames;
• means to identify time slots using a frame format;
• each time slot in said upstream channel able to contain at least one ATM cell;
• and
• means to multiplex access to said upstream shared channel using ATM packet transmission techniques.

A system for controlling access to a shared channel for cell transmission in a hybrid fiber optic/coaxial cable network, wherein the coaxial cable distribution portion of said network extends from a fiber node to a plurality of terminals within a community, having a tree and branch topology, comprising:

• a downstream broadcast channel from said fiber node to all terminals on said distribution network,
• a shared upstream channel, separate from said downstream broadcast channel, from all of said terminals to said fiber node;
• a network controller for central control of access of media transmissions from said terminals over said upstream channel;
• media access control protocols residing in said controller and in said terminals;
• an asynchronous transmission mode (ATM) multiplexer with said controller having ATM shared channel protocols to provide dynamic bandwidth allocation of said upstream channel;
• and
• means to grant access to said shared upstream channel to any of said terminals.

A system for controlling access to a shared channel for cell transmission in a hybrid fiber optic/coaxial cable network, wherein the coaxial cable distribution portion of said network extends from a fiber node to a plurality of terminals within a community, having a tree and branch topology, comprising:

• a downstream broadcast channel from said fiber node to all terminals on said distribution network,
• a shared upstream channel from all of said terminals to said fiber node;
• a network controller for central control of access of media transmissions from said terminals over said upstream channel;
• media access control protocols residing in said controller and in said terminals;
• an asynchronous transmission mode (ATM) multiplexer with said controller having ATM shared Channel protocols to provide dynamic bandwidth allocation of said upstream channel;
• and
• means to grant access to said shared upstream channel to any of said terminals;
• wherein said means to grant access to said shared upstream channel to any of said terminals, comprises:
• a media access control cell with protocols periodically inserted within broadcasts by said ATM multiplexer on said downstream channel of said coaxial cable distribution portion of said network to said terminals;
• said broadcasts on said downstream channel utilizing an ATM slotted transmission format;
• said media access control protocols dividing said downstream and upstream channels into frames and time slots within frames;
• means to identify time slots using a frame format;
• each time slot in said upstream channel able to contain at least one ATM cell;
• and
• means to multiplex access to said upstream shared channel using ATM packet transmission techniques.

A virtual connection media access control system for use in shared channel, shared media networks for controlling access to an upstream channel on the distribution portion of said network from terminals to a node to permit transmission of multimedia data comprising:

• a controller at said node storing media access control protocols for access to a coaxial distribution network;
• a plurality of terminals connected to said distribution network;
• a downstream broadcast channel from said node to all of said terminals;
• an upstream channel shared by said terminals to transmit ATM cells to said node;
• a virtual connection in said upstream channel between at least one source of said ATM cells within each of said terminals and said distribution network;
• said controller broadcasting a media access control cell periodically to said terminals;
• said media access control cell including frame information in said downstream broadcast and assigning time slots within said frames for upstream transmissions from said terminals;
• said terminals utilizing said media access control cell to determine transmission access times.

A virtual connection media access control system for use in shared channel, shared media networks for controlling access to an upstream channel on the distribution portion of said network from terminals to a node to permit transmission of multimedia data comprising:

• a controller at said node storing media access control protocols for access to a coaxial distribution network;
• a plurality of terminals connected to said distribution network;
• a downstream broadcast channel from said node to all of said terminals;
• an upstream channel shared by said terminals to transmit ATM cells to said node;
• said controller broadcasting a media access control cell periodically to said terminals;
• said media access control cell including frame information in said downstream broadcast and assigning time slots within said frames for upstream transmissions from said terminals;
• said terminals utilizing said media access control cell to determine transmission access times;
• means to specify modes of operation for upstream transmissions in time frames for said terminals;
• means to establish a plurality of virtual connections between a fiber node and said terminals;
• said media access control cell permitting contention frames for unknown virtual connections to said upstream channel;
• and
• means to verify receipt of transmissions to said fiber node from said virtual connections in said contention frames.

A method for providing media access control for a virtual connection in a shared medium network for controlling access to an upstream channel on the distribution portion of said network from terminals to a node to permit transmission of multimedia data, comprising the steps of:

• storing media access control protocols in a controller at said node and in all said terminals;
• broadcasting from said controller in a downstream broadcast channel from said node to all of said terminals a media access control cell periodically;
• including frame information in said media access control cell in said downstream broadcast and assigning time slots within said frames for upstream transmissions from said terminals;
• [and]
• utilizing said media access control cell at said terminals to determine transmission access times;
• and
• granting terminal transmission access times for the transmission of one or more cells addressed to said virtual connection from said terminal.

A method for providing media access control for a virtual connection in a shared medium network for controlling access to an upstream channel on the distribution portion of said network from terminal to a node to permit transmission of multimedia data, comprising the steps of:

• storing media access control protocols in a controller at said node and in all said terminals;
• broadcasting from said controller in a downstream broadcast channel from said node to all of said terminals a media access control cell periodically;
• including frame information in said media access control cell in said downstream broadcast and assigning time slots within said frames for upstream transmissions from said terminals;
• utilizing said media access control cell at said terminals to determine transmission access times;
• specifying modes of operation for upstream transmissions in time frames for said terminals;
• establishing a plurality of virtual connections between said node and said terminals;
• permitting contention frames for unknown virtual connections to said upstream channel;
• and
• verifying receipt of transmissions to said node in said contention frames from said unknown virtual connections.

A method for providing media access control for a virtual connection in hybrid fiber/coaxial cable network for controlling access to an upstream channel on the coaxial distribution portion of said network from terminals to a fiber node to permit transmission of multimedia data, comprising the steps of:

• storing media access control protocols in a controller at said fiber node and in all said terminals;
• an upstream channel shared by said terminals to transmit ATM cells to said fiber node;
• broadcasting from said controller in a downstream broadcast channel from said fiber node to all of said terminals a media access control cell periodically to said terminals;
• including frame information in said media access control cell in said downstream broadcast and assigning time slots within said frames for upstream transmissions from said terminals;
• utilizing said media access control cell at said terminals to determine transmission access times;
• and
• granting terminal transmission access times for the transmission of one or more ATM cells addressed to said virtual connection from said terminal.

A method for providing media access control for a virtual connection in hybrid fiber/coaxial cable network for controlling access to an upstream channel on the coaxial distribution portion of said network from terminals to a fiber node to permit transmission of multimedia data, comprising the steps of:

• storing media access control protocols in a controller at said fiber node and in all said terminals;
• an upstream channel shared by said terminals to transmit ATM cells to said fiber node;
• broadcasting from said controller in a downstream broadcast channel from said fiber node to all of said terminals a media access control cell periodically to said terminals;
• including frame information in said media access control cell said downstream broadcast and assigning time slots within said frames for upstream transmissions from said terminals;
• utilizing said media access control cell at said terminals to determine transmission access times;
• specifying modes of operation for upstream transmissions in time frames for said terminals;
• establishing a plurality of virtual connections between said fiber node and said terminals;
• permitting contention frames for unknown virtual connections to said upstream channel;
• and
• verifying receipt of transmissions to said fiber node in said contention frames from said unknown virtual connections.