A shared channel used to communicate between a cable modem termination system and multiple cable modems is managed to prevent and/or reduce the impact of congestion. If the average channel utilization is above a near-congestion threshold, a cable modem in an extended high consumption state is assigned a reduced data transmission priority for managed traffic. Priority for that cable modem is restored to a default preferred level when the channel usage by that cable modem drops below a predetermined level or when the average aggregate channel utilization by all cable modems drops below the near-congestion threshold.