session i is serviced by the scheduler in step 102 the content l i of the counter 126 is decremented in step 104 then if l i is not smaller than the content n i of the register 128 as determined in step 106 the entry for session i just extracted from the head of the rate fifo queue is queued back in step 108 to the tail of the same rate fifo queue otherwise a sub session of session i is classified as idle in step 1 10 and the entry is not queued back to the rate fifo queue after packet arrival in step 90 packet servicing is performed in step 102 so that every time a packet of session i is serviced by the scheduler the length l i is decremented in step 104 then if l i is not smaller than n i as determined in step 106 the entry for session i just extracted from the head of the rate fifo queue is queued back in step 108 to the tail of the same rate fifo queue otherwise a sub session of session i has become idle in step 110 and the extracted entry is not queued back to the rate fifo queue the session i is split in multiple sub sessions for scheduling purpose only and so the.