Patent ID: 7385993

Claim:
A queue scheduling mechanism in a data packet transmission system, the data packet transmission system including a transmission device for transmitting data packets, a reception device for receiving said data packets, a set of queue devices respectively associated with a set of priorities each defined by a priority rank in a plurality of priority ranks for storing each of data packets transmitted by said transmission device into the queue device corresponding to one of said priority ranks and a queue scheduler for reading, at each packet cycle, a data packet in one of said queue devices determined by a normal priority preemption algorithm, said queue scheduling mechanism comprising: a credit device that provides at each packet cycle a value N defining a priority rank to be considered by said queue scheduler, the considered priority rank is selected based on a pre-determined value related to all of said priority ranks which are associated with said queue scheduling mechanism, whereby a data packet is read by said queue scheduler from a queue device corresponding to the priority rank N instead of a queue device determined by the normal priority preemption algorithm, wherein said pre-determined value comprises a pre-determined percentage of occurrence of said considered priority rank relative to all of said priority ranks.