A headend of a shared data channel receives data packets, each data packet being addressed to a user of the shared data channel. A buffer of the headend queues the data packets, and a router of the headend assigns high transmittal priority to data packets addressed to users who have more recently received...http://www.google.com.tw/patents/US6304578?utm_source=gb-gplus-share專利 US6304578 - Packet routing and queuing at the headend of shared data channel
