Method and system for a high capacity cable network

A system comprising:

• a cable modem termination system (CMTS) operable to:
• communicate with a plurality of cable modems using a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers, wherein said plurality of cable modems belong to a single service group;
• determine a plurality of values of a performance metric, each one of said plurality of values of said performance metric corresponding to a respective one of said plurality of cable modems and a respective one of said OFDM subcarriers;
• for each one of said plurality of OFDM subcarriers, select physical layer parameters to be used for communication with said service group on said one of said OFDM subcarriers based on a plurality of values of said performance metric;
• broadcast a packet to said service group, wherein a threshold value of said performance metric required for reception of said packet is higher than a subset of said plurality of values of said performance metric, wherein the subset of said plurality of values corresponds to a subset of said plurality of modems;
• and
• partially or fully retransmit contents of said packet to said subset of said modems in a unicast or multicast packet.

A system comprising:

• a cable modem termination system (CMTS) operable to:
• communicate with a plurality of cable modems using a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers;
• select to use hierarchical modulation for a particular one of said OFDM subcarriers when a difference between a value of a performance metric measured for a first one of said plurality of cable modems on said particular one of said OFDM subcarriers and a value of said performance metric measured for a second one of said plurality of cable modems on said particular one of said OFDM subcarriers is greater than a predetermined amount;
• and
• select to use non-hierarchical modulation for said particular one of said OFDM subcarriers otherwise.

A system comprising:

• a cable modem termination system (CMTS) operable to:
• communicate with a plurality of cable modems using hierarchical modulation and a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers, wherein:
• both of more significant bits and less significant bits are transmitted on a first subset of said OFDM subcarriers for which each of said plurality of cable modems has a relatively-high value of a performance metric;
• and
• only more significant bits are transmitted on a second subset of said OFDM subcarriers for which one or more of said plurality of cable modems has a relatively-low value of said performance metric.