Wideband DOCSIS on catv systems using port-trunking

A process for performing downstream DOCSIS (Data Over Cable Service Interface Specification) in a point-to-multipoint environment comprising a cable modem termination system (CMTS) which includes one or more CMTS transmitters coupled to a plurality of cable modems (CMs) by a shared transmission medium, the process comprising:

• determining which of the plurality of cable modems is wideband capable and how many downstream channels each wideband capable cable modem can simultaneously use;
• sending an extended channel enable message to each wideband capable cable modem, said extended channel enable message identifying one or more downstream channels to which said wideband-capable cable modem should tune for reception of wideband downstream DOCSIS transmissions;
• processing, in a frame distributor, distribution of frames to CMTS transmitters transmitting on downstream channels to which a CM has been instructed to tune so as to schedule the frames in a manner facilitating the reassembly of the frames into proper order as necessary to meet quality of service requirements, including adding sequence numbers;
• and
• distributing the frames to the transmitters;
• transmitting the distributed frames addressed to a wideband capable cable modem on the one or more downstream channels to which said wideband capable cable modem has been instructed to tune;
• wherein processing further comprises:
• determining the particular downstreams to which each wideband DOCSIS CM is tuned using registration data and data from transmitted ECE messages and determining particular IP flows directed to each wideband CM from header data in packets received from a router;
• verifying which downstream channels to which a particular CM is tuned and which has an IP flow to be sent to it are available for transmission and determining quality of service requirement of each IP flow;
• scheduling guaranteed portions of constant bit rate flows and committed portions of variable bit rate flows on available downstream DOCSIS channels to which CMs are tuned which have IP flows with quality of service requirements which are constant bit rate or variable bit rate flows with guaranteed portions;
• generating frame release signals and release and transmit frames at scheduled times on appropriate downstream DOCSIS channels to fulfill the guaranteed bit rates of constant bit rate Quality of Service IP flows and to fulfill committed bit rate portions of variable bit rate Quality of Service IP flows;
• and
• for any wideband downstream CMs which have IP flows directed thereto with other than guaranteed bit rate Quality of Service IP flows or variable bit rate Quality of Service IP flows with committed portions, using any times on DOCSIS downstream channels to which the CMs are tuned when no releases of frames to the CM or other CMs are scheduled or when there is no traffic to release frames directed to the CMs which have IP flows directed thereto with other than guaranteed bit rate Quality of Service IP flows or variable bit rate Quality of Service IP flows with committed portions.

A process carried out in a cable modem (CM) during wideband DOCSIS (Data Over Cable Service Interface Specification) downstream processing, comprising the steps:

• powering up and locking onto a DOCSIS downstream and performing DOCSIS ranging including ranging and equalization and receiving time, frequency, phase and power offsets in a messages from a cable modem termination system (CMTS);
• sending an acknowledgement message if said ranging was successful and registering, in a registration message, with said CMTS as a CM in the system, said registration message including data regarding the wideband DOCSIS capability of said CM;
• receiving an Extended Channel Enable (ECE) message from said CMTS that indicates which DOCSIS downstream channels said CM should get ready to receive wideband DOCSIS data upon, and reacting thereto by setting up a plurality of DOCSIS receivers to receive data on the DOCSIS downstream channels designated in said ECE message;
• receiving a plurality of frames or packets transmitted simultaneously on a plurality of DOCSIS channels representing one or more IP flows;
• verifying that all packets or frames have been received that are supposed to be received;
• and putting said frames or packets into the correct order and delivering said frames or packets for further processing.

A process for performing wideband DOCSIS (Data Over Cable Service Interface Specification) transmissions upstream from a cable modem (CM) which is part of a plurality of cable modems coupled to a cable modem termination system (CMTS) via a shared transmission medium, comprising the steps:

• broadcasting from said CMTS a plurality of Upstream Channel Descriptor (UCD) messages, each of which defines the frequency, symbol rate, modulation type and other parameters of a DOCSIS upstream identified in said UCD message;
• after a CM has locked onto a downstream and sent a ranging burst, the CMTS makes measurements and performs equalization convergence and sends one or more messages downstream to said CM which give it time, frequency and power offsets and upstream equalization coefficients;
• after the CM has successfully ranged and sent an acknowledgment thereof and sent a registration message which advertises its capabilities, the CMTS receives these messages and stores at least some of the data therein indicating the CM's wideband capabilities and determines whether the CM is wideband capable;
• the CMTS receives upstream bandwidth requests from the CM and from other CMs and uses registration data to determine which CMs are upstream wideband DOCSIS capable and determines how many upstream channels each CM which has requested upstream bandwidth can simultaneously transmit upon;
• the CMTS analyzes the requested upstream traffic and registration and subscription data and determines which upstream channels to assign to which CMs for upstream wideband DOCSIS operation;
• the CMTS uses a quality of service algorithm to schedule upstream grants for each IP flow from each CM and generates separate MAP messages for each DOCSIS upstream a CM is scheduled to use for upstream wideband DOCSIS, each MAP message scheduling when the CM or CMS having grants in the MAP message may transmit on the DOCSIS upstream to which the MAP message pertains;
• the CMTS uses the grants in the MAP messages to determine which CMs that are wideband DOCSIS capable need to use multiple upstream DOCSIS channels, and sends an ECE message to each CM which is being authorized to send upstream wideband DOCSIS transmissions, each ECE message designating which upstream DOCSIS channels the CM may use and sends the MAP messages;
• after the CMs which have been enabled for upstream wideband DOCSIS have transmitted data according to the MAP, ECE and UCD messages, the CMTS receives all frames and passes them to a frame collector which makes sure all frames are there and puts them into the correct order for delivery.

A process carried out in a cable modem (CM) which is one of a plurality of cable modems coupled by a shared transmission medium to a cable modem termination system (CMTS) for performing upstream wideband DOCSIS (Data Over Cable Service Interface Specification) transmissions, comprising the steps:

• powering up, finding a DOCSIS downstream and locking onto it, and using a DOCSIS upstream to perform conventional DOCSIS ranging including ranging and equalization and sending an acknowledgment message indicating whether or not ranging has been successful, and sending a registration message to said CMTS which advertises the CM's wideband upstream DOCSIS capabilities;
• receiving a plurality of Upstream Channel Descriptor (UCD) messages, each of which describes the frequency, symbol rate, modulation type and other parameters of a DOCSIS upstream;
• receiving requests from user applications to send data upstream and responding thereto by sending upstream bandwidth requests;
• receiving an Extended Channel Enable message which indicates which upstream DOCSIS channels to use for wideband DOCSIS upstream operations, and receiving a plurality of MAP messages, each pertaining to a single DOCSIS upstream channel and defining when said CM may transmit on said channel;
• setting up the transmitters of said CM to transmit on the upstream DOCSIS channels designated in said ECE messages, and timing the transmission of upstream data on the designated channels per grants in said MAP messages pertaining to said channels.

A cable modem apparatus comprising:

• a plurality of DOCSIS (Data Over Cable Service Interface Specification) transmitters, each having an input;
• a frame distributor having a plurality of outputs coupled to said inputs of said transmitters and having an input;
• a plurality of DOCSIS receivers having inputs coupled to a hybrid fiber coaxial cable system and a plurality of outputs;
• a frame collector having a plurality of inputs coupled to said plurality of outputs of said plurality of DOCSIS receivers and having an output;
• a network interface or bus interface having an input coupled to said output of said frame collector and having an output coupled to said frame distributor;
• and
• control computer coupled to said plurality of DOCSIS transmitters and said plurality of DOCSIS receivers and said frame distributor and said frame collector and programmed to operations of said cable modem to perform the following functions:
• powering up, finding a DOCSIS downstream and locking onto it, and using a DOCSIS upstream to perform DOCSIS ranging including ranging and equalization and sending an acknowledgment message indicating whether or not ranging has been successful, and sending a registration message to a CMTS which advertises the CM's wideband upstream DOCSIS capabilities;
• receiving a plurality of Upstream Channel Descriptor (UCD) messages, each of which describes the frequency, symbol rate, modulation type and other parameters of a DOCSIS upstream;
• receiving requests from user applications to send data upstream and responding thereto by sending upstream bandwidth requests;
• receiving an Extended Channel Enable message which indicates which upstream DOCSIS channels to use for wideband DOCSIS upstream operations, and receiving a plurality of MAP messages, each pertaining to a single DOCSIS upstream channel and defining when said CM may transmit on said channel;
• setting up the transmitters of said CM to transmit on the upstream DOCSIS channels designated in said Extended Channel Enable message in accordance with the parameters in the UCD message pertaining to the appropriate upstream channel, and timing the transmission of upstream data on the designated channels per grants in said MAP messages pertaining to said channels.

A cable modem termination system capable of wideband DOCSIS (Data Over Cable Service Interface Specification) operation, comprising:

• a plurality of DOCSIS transmitters each having an output for coupling to a hybrid fiber coaxial (HFC) cable system, and each having an input;
• a frame distributor having an input and having a plurality of outputs, each said outputs coupled to an input of one of said DOCSIS transmitters, and having an input;
• a plurality of DOCSIS receivers, each having an input for coupling to said HFC system, and each having an output;
• a frame collector having a plurality of inputs each coupled to an output of one of said DOCSIS receivers and having an output;
• a router having an input coupled to said output of said frame collector and having an output coupled to said input of said frame distributor;
• and
• a control computer coupled to said plurality of DOCSIS transmitters and receivers and to said frame distributor and to said frame collector and to said router, and programmed to orchestrate the following functions:
• receiving registration message data from CMs and determining therefrom which cable modems are wideband DOCSIS downstream capable and how many downstream channels each can simultaneously use;
• sending an extended channel enable message to each wideband capable cable modem telling it which downstream channels to which it should tune for reception of wideband downstream DOCSIS transmissions;
• processing incoming frames from said router to be sent downstream to a particular CM in a frame distributor to schedule the distribution of frames to the various CMTS downstream transmitters transmitting on the downstream channels to which said CM is tuned so as to meet quality of service requirements, and adding sequence numbers or other processing to guarantee the frames can be put into the proper order at the CM, and distributing the frames to said CMTS downstream transmitters in accordance with said schedule;
• transmitting the distributed frames addressed to a particular CM to that CM on the downstream channels to which said CM has been instructed to tune.