I am testing the throughput offered by the POS-STM4 card on 2 7304 connected back to back. What I can see is the throughput(layer2 Bit rate) is not reaching the desired level(I am expecting it to go upto 599Mbps. The second thing which worries me is throughput varies with the packet size. For 60 byte packets its 551 and increses upto 596Mbps for 1500byte packets but never reaching 599Mbps. Is it the expected behaviour? appriciate if any documents/pointers on STM4 throughput is available.