Method and apparatus enabling multiple access on a broadband communication network

A method of allocating transmission bandwidth among a plurality of stations interconnected with a common controller via a transmission medium having a multiple access upstream channel, at least one of said plurality of stations originating variable bit rate (VBR) traffic, said method comprising the steps of:

• dividing time in said upstream channel on said transmission medium into a series of successive time frames;
• dividing each of the time frames into a plurality of time slots;
• allocating a guaranteed minimum number of time slots of said plurality of time slots to at least one station of said plurality of stations, on an initial basis, when said at least one station contends for said plurality of time slots;
• allocating said guaranteed minimum number of time slots for continued use by said at least one station in response to a first reservation indication contained in a first plurality of messages inserted by said at least one station in said guaranteed minimum number of time slots;
• allocating a plurality of additional time slots of said plurality of time slots to said at least one station when the at least one station signals a high activity period;
• allocating said plurality additional time slots for continued use by said at least one station during said high activity period, in response to a second reservation indication contained in a second plurality of messages inserted by said at least one station in said plurality of additional time slots;
• and
• releasing said plurality additional time slots when the at least one station signals a decrease in its activity.

A method of allocating transmission bandwidth among a plurality of stations interconnected with a common controller via a transmission medium having a multiple access upstream channel, said method comprising the steps of:

• dividing time in said upstream channel on said transmission medium into a series of successive time frames;
• dividing each of the time frames into a plurality of time slots;
• providing a plurality of status messages indicative of a status of each of said plurality of time slots to said plurality of stations from said common controller, said plurality of status messages being provided in a downstream channel;
• and responsive to said plurality of status messages, said plurality of stations (a) transmitting a new packet in one of said plurality of time slots, (b) continuing to transmit an on-going message in one of said plurality of time slots, or (c) allowing other ones of said plurality of stations to transmit in one of said time slots.

A method for allowing a plurality of stations originating constant bit rate (CBR) and variable bit rate (VBR) types of traffic to share a transmission medium having a multiple access upstream channel to a common controller, said upstream channel including a series of successive time frames, and each time frame including a plurality of time slots, said method comprising the steps of:

• determining the type of traffic to be transmitted by a station seeking access to the transmission medium,
• for CBR traffic, allocating, on an initial basis, one or more of said plurality of time slots to a first station of said plurality of stations that contends for said plurality of time slots;
• and
• reserving said one or more of said plurality of time slots for continued use by said first station in response to a first reservation indication contained in a first plurality of messages inserted by said first station in said one or more of said plurality of time slots;
• and
• for VBR traffic, allocating a guaranteed minimum number of time slots of said plurality of time slots to a second station of said plurality of stations, on an initial basis, when said second station contends for said plurality of time slots;
• reserving said guaranteed minimum number of time slots for continued use by said second station in response to a second reservation indication contained in a second plurality of messages inserted by said second station in said guaranteed minimum number of time slots;
• allocating a plurality additional time slots of said plurality of time slots to said second station when the second station signals a high activity period;
• reserving said plurality of additional time slots for continued use by said second station during said high activity period, in response to a third reservation indication:
• contained in a third plurality of messages inserted by said second station in said plurality of additional time slots;
• and
• releasing said plurality of additional time slots when the second station signals a decrease in its activity.

A communication system, including:

• a transmission network, wherein a plurality of stations are interconnected with a common controller via a transmission medium having a multiple access upstream channel and a broadcast downstream channel, each of said upstream and downstream channels defining a sequence of time frames, each of the time frames including a plurality of time slots, and
• means for allowing any of said plurality of stations requiring isocbronous, asynchronous or sporadic transmission capacity to transmit signals in any available time slots of the plurality of time slots on said upstream channel without interfering with each other,
• wherein the means for allowing includes:
• means in said common controller for transmitting status information regarding the plurality of time slots in said upstream channel to said plurality of stations, said status information being transmitted in said downstream channel;
• means in said plurality of stations for receiving said status information and in response, interpreting and creating a control signal indicating whether to transmit or not, and
• means in said plurality of stations arranged so that, if said plurality of stations transmit data in one or more of said plurality of time slots in said upstream channel, said plurality of stations include an indication of sustained use of said one or more of said plurality of time slots in subsequent time frames in the sequence of time frames.

A method for providing shared access on a broadband cable network having a plurality of upstream and downstream RF channels, said method comprising the steps of:

• dividing a time domain for a particular RF channel into a series of successive time frames, each time frame having a plurality of time slots,
• when a station desires transmit information in the upstream direction, inserting the information into an available time slot of the plurality of time slots in one of said plurality of upstream channels;
• and
• determining availability of the plurality of time slots in said upstream channel in accordance with a plurality of time slot status messages received via one of said plurality of downstream channels.

An apparatus for allocating transmission bandwidth among a plurality of stations interconnected with a common controller via a transmission medium having a multiple access upstream channel, said apparatus comprising:

• means for (a) dividing time in said upstream channel on said transmission medium into a series of successive time frames and (b) dividing each of the time frames into a plurality of time slots;
• means for providing a plurality of status messages indicative of a status of each of said plurality of time slots to said plurality of stations from said common controller, said plurality of status messages being provided in a downstream channel;
• and
• means in said plurality of stations, responsive to said plurality of status messages, for (a) transmitting a new packet in one of said time slots, (b) continuing to transmit an on-going message in one of said time slots, or (c) allowing other ones of said stations to transmit in said one of said time slots.