Hello, Yuri What is the right way to define new pkt type in ns2? I add some new type of control message in mcast_ctrl.cc, so I modify that file, adding in new pkt name, etc. then I modify the packt.h file to define the pkt type. It doesn't work, the nam animator was showing wrong names for the particular control pkt generated, same error also appear in the out.tr file. Tks in advance, shuqian