Hi, I think you're talking about the awk scripts to interpret the output file given by the simulator, or not? Because that files look for the "d". I was talking about the second method:
"[Method 2---modify C++ code] The basic idea is to insert two fields, sendtime_ and pkt_id_, in the hdr_cmn header. When packets are sent, the packet id and send time is recorded in the sender trace file. Then when packets are received at the destination, the packet id and receiving time is recorded in the receiver trace file. So I prepare two agents, mudp and mudpsink to do the jobs. Mudp is the extension of udp agent. It only overrides the sendmsg function to keep download the packet id and sendtime in the user specified file." The agent by itself records special events needed to calculate Jitter, Data loss and delay. This is a way to measure the channel characterists with UDP flows.