first of all you should determine which layer is responsible for dropping the packet? I suppose it's routing agent, for example. then, put this line wherever you want to drop the packet p: drop(p, DROP_RTR_YOUR_REASON); put this at line 97 in file %NS_DIRECTORY%/trace/cmu-trace.h #define DROP_RTR_YOUR_REASON "XXX" then run the following command: touch %NS_DIRECTORY%/trace/cmu-trace.cc now you can make the ns code. when the ns drops a packet under your condition, the trace will be like this: D 2.828954441 1 RTR XXX 2 cbr 512 [0 0 0 0] ------- [1:0 20:0 32 0] [2] 0 3 0
Good luck! On Fri, Aug 3, 2012 at 4:49 PM, Giorgos Karanikas <computera...@gmail.com>wrote: > > > To provide some more info: > > Suppose I have the following topology: > > http://old.nabble.com/file/p34250683/topology.jpeg > > What I want is node D to drop packets from some specific nodes. What I've > done is the following: > I added one variables in the node.cc && node.h to define if the packets > from > that node are to be dropped and I also added one variable to the packet.cc > (in the header of the packet) to define after how many hops the packet is > to > be dropped. > > In the connector.cc I have changed the recv(Packet* p, Handler* h) function > in order to check if the packet is to be dropped. If not then I update the > packet's hop variable I created (increase it to show the number of hops > that > packet has been over). > If the packet is to be dropped though I call the drop(p) function. > > As I said that does not work properly since (probably) the Packet::free(p) > function is used as I don't see the packet drop events in the traces. > > Anyone knows what I'm doing wrong? Should I define a drop-target for D and > connect it to the agents from the nodes that I want packets to be dropped? > And exactly how am I supposed to do that (since I tried but I failed)? > > Thanks in advance and I hope that these information give a clearer view of > my situation. > -- > View this message in context: > http://old.nabble.com/Properly-drop-packet-tp34250208p34250683.html > Sent from the ns-users mailing list archive at Nabble.com. > >
