diff --git a/examples/wireless/wifi-simple-adhoc-grid.cc b/examples/wireless/wifi-simple-adhoc-grid.cc index 7f7e2fb2d..d722ed193 100644 --- a/examples/wireless/wifi-simple-adhoc-grid.cc +++ b/examples/wireless/wifi-simple-adhoc-grid.cc @@ -31,7 +31,7 @@ // n0 n1 n2 n3 n4 // // the layout is affected by the parameters given to GridPositionAllocator; -// by default, GridWidth is 5 and numNodes is 25.. +// by default, GridWidth is 5 (nodes per row) and numNodes is 25.. // // There are a number of command-line options available to control // the default behavior. The list of available command-line options @@ -43,12 +43,26 @@ // // For instance, for this configuration, the physical layer will // stop successfully receiving packets when distance increases beyond -// the default of 500m. -// To see this effect, try running: +// the default of 100m. The cutoff is around 116m; below that value, the +// received signal strength falls below the (default) RSSI limit of -82 dBm +// used by Wi-Fi's threshold preamble detection running. // -// ./ns3 run "wifi-simple-adhoc-grid --distance=500" -// ./ns3 run "wifi-simple-adhoc-grid --distance=1000" -// ./ns3 run "wifi-simple-adhoc-grid --distance=1500" +// To see this effect, try running at a larger distance, and no packet +// reception will be reported: +// +// ./ns3 run "wifi-simple-adhoc-grid --distance=200" +// +// The default path through the topology will follow the following node +// numbers: 24->23->18->13->12->11->10->5->0 +// +// To see this, the following Bash commands will list the UDP packet +// transmissions hop-by-hop, if tracing is enabled: +// +// ./ns3 run "wifi-simple-adhoc-grid --tracing=1" +// grep ^t wifi-simple-adhoc-grid.tr | grep Udp | grep -v olsr | less +// +// By changing the distance to a smaller value, more nodes can be reached +// by each transmission, and the number of forwarding hops will decrease. // // The source node and sink node can be changed like this: // @@ -67,6 +81,9 @@ // // tcpdump -r wifi-simple-adhoc-grid-0-0.pcap -nn -tt // +// or you can examine the text-based trace wifi-simple-adhoc-grid.tr with +// an editor. +// #include "ns3/command-line.h" #include "ns3/config.h" @@ -133,7 +150,7 @@ int main(int argc, char* argv[]) { std::string phyMode("DsssRate1Mbps"); - double distance = 500; // m + double distance = 100; // m uint32_t packetSize = 1000; // bytes uint32_t numPackets = 1; uint32_t numNodes = 25; // by default, 5x5