Hi, You can see it on ns-2.34/tcl/ex/wireless-flooding.tcl and ns-2.34/tcl/ex/802.11/broadcast_validation.tcl witch uses a specific broadcast agent.
Further details in ns-2.34/common/packet.h on lines 676 and 677: init(p); // Initialize bits_[] (HDR_CMN(p))->next_hop_ = -2; // -1 reserved for IP_BROADCAST (HDR_CMN(p))->last_hop_ = -2; // -1 reserved for IP_BROADCAST Regards, Alysson Oliveira 2012/5/2, Frank Wetzels <frank.wetz...@cwi.nl>: > > Hi, > > I have no solution for you in NS2. However, I have a remark on your > address/port choice. > I guess that by choosing -1, you fill the address field with 255.255.255.255 > as IP address > in dotted decimal notation? The port number choice of 0 is a bit strange. > Although you are using IP broadcast > you - strictly speaking - still need a legitimate port number. Indeed, you > choose a particular protocol by choosing > the port address. As an example, DHCP uses IP broadcast initially based on > UDP67 / UDP68. > > Regards, > Frank > > On May 1, 2012, at 5:36 AM, Paulo Robson S. F. wrote: > >> >> Hi, >> >> I want to broadcast a packet using an udp agent. I found some solutions >> at >> this maillist but >> neither satisfactory. >> >> I just want to send broadcast packet from 1 node to another 2 nodes in >> his >> range. My idea was >> change the dst ip to -1 and dst port to 0 because i saw somewhere that is >> the way to broadcast. >> >> I'm using the 802.11Ext model of MAC, the new module of the NS 2.34 >> >> Well, I made this way: >> >> set udp0 [new Agent/UDP] >> $ns attach-agent $node $udp0 >> set cbr2 [new Application/Traffic/CBR] >> >> $cbr2 set packetSize_ 128 >> $cbr2 set interval_ 0.015 >> $cbr2 set random_ 1 >> $cbr2 set maxpkts_ 1000 >> >> $cbr2 attach-agent $udp0 >> >> #to broadcast i used this: >> $udp0 set dst_addr_ -1 >> $udp0 set dst_port_ 0 >> >> In the trace file seems to be right, but i dont know if only this change >> of >> address and port of destination >> is indeed a broadcast to all neighbors. >> >> First lines of trace file: >> s 0.500000000 _2_ AGT --- 0 cbr 128 [0 0 0 0] ------- [2:0 -1:0 32 0] >> [0] >> 0 0 >> r 0.500000000 _2_ RTR --- 0 cbr 128 [0 0 0 0] ------- [2:0 -1:0 32 0] >> [0] >> 0 0 >> s 0.500000000 _2_ RTR --- 0 cbr 148 [0 0 0 0] ------- [2:0 -1:0 32 0] >> [0] >> 0 0 >> s 0.500025000 _2_ MAC --- 0 cbr 176 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [0] 0 0 >> r 0.500546664 _1_ MAC --- 0 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [0] 1 0 >> r 0.500546841 _0_ MAC --- 0 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [0] 1 0 >> r 0.500571664 _1_ RTR --- 0 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [0] 1 0 >> r 0.500571664 _1_ AGT --- 0 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 31 >> 0] [0] 1 0 >> r 0.500571841 _0_ RTR --- 0 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [0] 1 0 >> r 0.500571841 _0_ AGT --- 0 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 31 >> 0] [0] 1 0 >> s 0.507505094 _2_ AGT --- 1 cbr 128 [0 0 0 0] ------- [2:0 -1:0 32 0] >> [1] >> 0 0 >> r 0.507505094 _2_ RTR --- 1 cbr 128 [0 0 0 0] ------- [2:0 -1:0 32 0] >> [1] >> 0 0 >> s 0.507505094 _2_ RTR --- 1 cbr 148 [0 0 0 0] ------- [2:0 -1:0 32 0] >> [1] >> 0 0 >> s 0.507530094 _2_ MAC --- 1 cbr 176 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [1] 0 0 >> r 0.508051758 _1_ MAC --- 1 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [1] 1 0 >> r 0.508051934 _0_ MAC --- 1 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [1] 1 0 >> r 0.508076758 _1_ RTR --- 1 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [1] 1 0 >> r 0.508076758 _1_ AGT --- 1 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 31 >> 0] [1] 1 0 >> r 0.508076934 _0_ RTR --- 1 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 32 >> 0] [1] 1 0 >> r 0.508076934 _0_ AGT --- 1 cbr 148 [0 ffffffff 2 0] ------- [2:0 -1:0 >> 31 >> 0] [1] 1 0 >> >> >> Thanks guys >> >> >> Att, >> >> -- >> Paulo Robson SF >> Computação UFC >> Semestre VII > > > -- Alysson Oliveira
