<span style="font-family:arial;font-size:14px">Hi all,</span><br style="font-family:arial;font-size:14px"><br style="font-family:arial;font-size:14px"><span style="font-family:arial;font-size:14px">  I am using ndnsim2.1. My purpose is to set the congestion mark when the packet dequeue(if its delay is long).</span><br style="font-family:arial;font-size:14px"><span style="font-family:arial;font-size:14px">  The idea of adding a congestion mark: first add the MyCongestionMark field in the Data, and then set MyCongestionMark to a certain number when dequeue(indicate congestion). </span><br style="font-family:arial;font-size:14px"><span style="font-family:arial;font-size:14px">  The question now is that where add MyCongestionMark field is in the Data, but in function dequeue() of the queue are all Packet,and I can't use packet.setMyCongestionMark() like data.setMyCongestionMark(). Is my idea right and How to convert Packet to Data in dequeue()?Thank you.</span><br style="font-family:arial;font-size:14px"><br style="font-family:arial;font-size:14px"><span style="font-family:arial;font-size:14px">Best regards,</span><br style="font-family:arial;font-size:14px"><span style="font-family:arial;font-size:14px">Leo</span>