[ns] huge delay between the application layer and the MAC layer!

Sun Apr 9 03:52:50 PDT 2006

Dear friends:
    I modified test-suite-smac-multihop.tcl to test the performance of SMAC
with a linear topology, like this:
0---->1---->2---->3---->4---->5---->6----->7------>8-------->9
where node 0 is the source and node 9 is the sink.
node 0 sent cbr message(packetsize==100b) to node 9. When the cbr interval
is 10sec, I got the end-to-end delay
is 9.07 sec. However, when I set the cbr interval to 1.0 sec, I got the
end-to-end delay is 400 sec!!!
I use the command   awk '$27=="[20]"{print $0}' smac1.tr   to track the
packet 20 sent from node 0 to node 9,and I got:

s 118.084104657 _0_ AGT  --- 4326 cbr 100 [0.00 0 0] [energy 991.178745 ei
8.685 es 0.022 et 0.030 er 0.053] ------- [0:0 9:0 32 0] [20] 0 0
r 118.084104657 _0_ RTR  --- 4326 cbr 100 [0.00 0 0] [energy 991.178745 ei
8.685 es 0.022 et 0.030 er 0.053] ------- [0:0 9:0 32 0] [20] 0 0
s 139.063245667 _0_ RTR  --- 4326 cbr 120 [0.00 0 0] [energy 990.565422 ei
9.198 es 0.027 et 0.043 er 0.127] ------- [0:0 9:0 32 1] [20] 0 0
s 186.104216667 _0_ MAC  --- 4326 cbr 120 [0.07 1 0] [energy 982.275097 ei
15.663 es 0.030 et 0.684 er 1.303] ------- [0:0 9:0 32 1] [20] 0 0
s 186.158218000 _0_ MAC  --- 4326 cbr 120 [0.01 1 0] [energy 982.259877 ei
15.663 es 0.030 et 0.696 er 1.306] ------- [0:0 9:0 32 1] [20] 0 0
r 186.201218667 _1_ MAC  --- 4326 cbr 120 [0.01 1 0] [energy 980.432215 ei
17.229 es 0.028 et 0.883 er 1.387] ------- [0:0 9:0 32 1] [20] 0 0
r 186.201243667 _1_ RTR  --- 4326 cbr 120 [ 0.01 1 0] [energy 980.432215 ei
17.229 es 0.028 et 0.883 er 1.387] ------- [0:0 9:0 32 1] [20] 0 0
f 186.201243667 _1_ RTR  --- 4326 cbr 120 [0.01 1 0] [energy 980.432215 ei
17.229 es 0.028 et 0.883 er 1.387] ------- [0:0 9:0 31 2] [20] 0 0
s 186.250220000 _1_ MAC  --- 4326 cbr 120 [0.07 2 1] [energy 980.422520 ei
17.233 es 0.028 et 0.886 er 1.390] ------- [0:0 9:0 31 2] [20] 0 0
s 186.304221333 _1_ MAC  --- 4326 cbr 120 [0.01 2 1] [energy 980.407301 ei
17.233 es 0.028 et 0.898 er 1.393] ------- [0:0 9:0 31 2] [20] 0 0
r 186.347222000 _2_ MAC  --- 4326 cbr 120 [0.01 2 1] [energy 985.166360 ei
12.189 es 0.034 et 0.439 er 2.119] ------- [0:0 9:0 31 2] [20] 0 0
r 186.347247000 _2_ RTR  --- 4326 cbr 120 [0.01 2 1] [energy 985.166360 ei
12.189 es 0.034 et 0.439 er 2.119] ------- [0:0 9:0 31 2] [20] 0 0
f 186.347247000 _2_ RTR  --- 4326 cbr 120 [0.01 2 1] [energy 985.166360 ei
12.189 es 0.034 et 0.439 er 2.119] ------- [0:0 9:0 30 3] [20] 0 0
s 461.824239333 _2_ MAC  --- 4326 cbr 120 [0.07 3 2] [energy 962.752857 ei
21.702 es 0.087 et 2.304 er 13.005] ------- [0:0 9:0 30 3] [20] 0 0
s 461.878240667 _2_ MAC  --- 4326 cbr 120 [ 0.01 3 2] [energy 962.737637 ei
21.702 es 0.087 et 2.316 er 13.008] ------- [0:0 9:0 30 3] [20] 0 0
r 461.921241333 _3_ MAC  --- 4326 cbr 120 [0.01 3 2] [energy 962.308465 ei
26.268 es 0.085 et 0.933 er 10.263] ------- [0:0 9:0 30 3] [20] 0 0
r 461.921266333 _3_ RTR  --- 4326 cbr 120 [0.01 3 2] [energy 962.308465 ei
26.268 es 0.085 et 0.933 er 10.263] ------- [0:0 9:0 30 3] [20] 0 0
f 461.921266333 _3_ RTR  --- 4326 cbr 120 [0.01 3 2] [energy 962.308465 ei
26.268 es 0.085 et 0.933 er 10.263] ------- [0:0 9:0 29 4] [20] 0 0
s 461.971242667 _3_ MAC  --- 4326 cbr 120 [0.07 4 3] [energy 962.298552 ei
26.272 es 0.085 et 0.937 er 10.267] ------- [0:0 9:0 29 4] [20] 0 0
s 462.025244000 _3_ MAC  --- 4326 cbr 120 [0.01 4 3] [energy 962.283332 ei
26.272 es 0.085 et 0.949 er 10.270] ------- [0:0 9:0 29 4] [20] 0 0
r 462.068244667 _4_ MAC  --- 4326 cbr 120 [0.01 4 3] [energy 971.413400 ei
23.562 es 0.095 et 0.902 er 3.883] ------- [0:0 9:0 29 4] [20] 0 0
r 462.068269667 _4_ RTR  --- 4326 cbr 120 [0.01 4 3] [energy 971.413400 ei
23.562 es 0.095 et 0.902 er 3.883] ------- [0:0 9:0 29 4] [20] 0 0
f 462.068269667 _4_ RTR  --- 4326 cbr 120 [0.01 4 3] [energy 971.413400 ei
23.562 es 0.095 et 0.902 er 3.883] ------- [0:0 9:0 28 5] [20] 0 0
s 462.137246000 _4_ MAC  --- 4326 cbr 120 [0.07 5 4] [energy 971.399338 ei
23.570 es 0.095 et 0.905 er 3.887] ------- [0:0 9:0 28 5] [20] 0 0
s 462.191247333 _4_ MAC  --- 4326 cbr 120 [0.01 5 4] [energy 971.384118 ei
23.570 es 0.095 et 0.917 er 3.890] ------- [0:0 9:0 28 5] [20] 0 0
r 462.234248000 _5_ MAC  --- 4326 cbr 120 [ 0.01 5 4] [energy 968.177702 ei
26.944 es 0.091 et 0.963 er 3.684] ------- [0:0 9:0 28 5] [20] 0 0
r 462.234273000 _5_ RTR  --- 4326 cbr 120 [0.01 5 4] [energy 968.177702 ei
26.944 es 0.091 et 0.963 er 3.684] ------- [0:0 9:0 28 5] [20] 0 0
f 462.234273000 _5_ RTR  --- 4326 cbr 120 [0.01 5 4] [energy 968.177702 ei
26.944 es 0.091 et 0.963 er 3.684] ------- [0:0 9:0 27 6] [20] 0 0
s 463.407240000 _5_ MAC  --- 4326 cbr 120 [0.07 6 5] [energy 968.135415 ei
26.977 es 0.091 et 0.969 er 3.687] ------- [0:0 9:0 27 6] [20] 0 0
s 463.461241333 _5_ MAC  --- 4326 cbr 120 [0.01 6 5] [energy 968.120196 ei
26.977 es 0.091 et 0.981 er 3.690] ------- [0:0 9:0 27 6] [20] 0 0
r 463.504242000 _6_ MAC  --- 4326 cbr 120 [0.01 6 5] [energy 971.916235 ei
24.327 es 0.096 et 0.933 er 2.593] ------- [0:0 9:0 27 6] [20] 0 0
r 463.504267000 _6_ RTR  --- 4326 cbr 120 [0.01 6 5] [energy 971.916235 ei
24.327 es 0.096 et 0.933 er 2.593] ------- [0:0 9:0 27 6] [20] 0 0
f 463.504267000 _6_ RTR  --- 4326 cbr 120 [0.01 6 5] [energy 971.916235 ei
24.327 es 0.096 et 0.933 er 2.593] ------- [0:0 9:0 26 7] [20] 0 0
s 465.079238667 _6_ MAC  --- 4326 cbr 120 [ 0.07 7 6] [energy 971.856213 ei
24.380 es 0.096 et 0.936 er 2.596] ------- [0:0 9:0 26 7] [20] 0 0
s 465.133240000 _6_ MAC  --- 4326 cbr 120 [0.01 7 6] [energy 971.840993 ei
24.380 es 0.096 et 0.948 er 2.599] ------- [0:0 9:0 26 7] [20] 0 0
r 465.176240667 _7_ MAC  --- 4326 cbr 120 [0.01 7 6] [energy 970.584495 ei
25.467 es 0.095 et 0.933 er 2.788] ------- [0:0 9:0 26 7] [20] 0 0
r 465.176265667 _7_ RTR  --- 4326 cbr 120 [0.01 7 6] [energy 970.584495 ei
25.467 es 0.095 et 0.933 er 2.788] ------- [0:0 9:0 26 7] [20] 0 0
f 465.176265667 _7_ RTR  --- 4326 cbr 120 [0.01 7 6] [energy 970.584495 ei
25.467 es 0.095 et 0.933 er 2.788] ------- [0:0 9:0 25 8] [20] 0 0
s 465.250242000 _7_ MAC  --- 4326 cbr 120 [0.07 8 7] [energy 970.569341 ei
25.476 es 0.095 et 0.936 er 2.791] ------- [0:0 9:0 25 8] [20] 0 0
s 465.304243333 _7_ MAC  --- 4326 cbr 120 [0.01 8 7] [energy 970.554121 ei
25.476 es 0.095 et 0.948 er 2.794] ------- [0:0 9:0 25 8] [20] 0 0
r 465.347244000 _8_ MAC  --- 4326 cbr 120 [0.01 8 7] [energy 970.609173 ei
26.123 es 0.094 et 0.898 er 2.141] ------- [0:0 9:0 25 8] [20] 0 0
r 465.347269000 _8_ RTR  --- 4326 cbr 120 [ 0.01 8 7] [energy 970.609173 ei
26.123 es 0.094 et 0.898 er 2.141] ------- [0:0 9:0 25 8] [20] 0 0
f 465.347269000 _8_ RTR  --- 4326 cbr 120 [0.01 8 7] [energy 970.609173 ei
26.123 es 0.094 et 0.898 er 2.141] ------- [0:0 9:0 24 9] [20] 0 0
s 465.416245333 _8_ MAC  --- 4326 cbr 120 [0.07 9 8] [energy 970.595111 ei
26.131 es 0.094 et 0.901 er 2.144] ------- [0:0 9:0 24 9] [20] 0 0
s 465.470246667 _8_ MAC  --- 4326 cbr 120 [0.01 9 8] [energy 970.579891 ei
26.131 es 0.094 et 0.913 er 2.147] ------- [0:0 9:0 24 9] [20] 0 0
r 465.513247333 _9_ MAC  --- 4326 cbr 120 [0.01 9 8] [energy 976.607684 ei
21.034 es 0.102 et 0.265 er 1.838] ------- [0:0 9:0 24 9] [20] 0 0
r 465.513272333 _9_ RTR  --- 4326 cbr 120 [0.01 9 8] [energy 976.607684 ei
21.034 es 0.102 et 0.265 er 1.838] ------- [0:0 9:0 24 9] [20] 0 0
r 465.513272333 _9_ AGT  --- 4326 cbr 100 [0.01 9 8] [energy 976.607684 ei
21.034 es 0.102 et 0.265 er 1.838] ------- [0:0 9:0 24 9] [20] 0 0

>From the information above we can see that there is a huge delay for the
application layer to transmit the packet to the MAC layer.I dont't know why.
Can you help me? The tcl script and the awk script used to calculate
end-to-end delay are attached!
Any suggestions will be appreciated! Thank you!

Best regards!
David