[ns] Different TCP-Packetsizes

[Erwin Haller]

Hi !!

I have a very serious and weird problem. I make simulations with wireless
nodes and i set the MAC/802_11 bandwidth_ to 512000. I use the Shadowing
Model and want to simulate the throughput over different distances from
one node to another and over different TCP packetsizes. My problem is now,
that I can't explain if the packetsize goes higher than 4082, the packets
were droppped and the trace file looks like:  
+ 5.008042 1 0 tcp 60 ------- 2 1.0.1.0 0.0.0.0 0 2 
- 5.008042 1 0 tcp 60 ------- 2 1.0.1.0 0.0.0.0 0 2 
r 5.00909 1 0 tcp 60 ------- 2 1.0.1.0 0.0.0.0 0 2 
+ 5.00909 0 1 ack 40 ------- 2 0.0.0.0 1.0.1.0 0 3 
- 5.00909 0 1 ack 40 ------- 2 0.0.0.0 1.0.1.0 0 3 
r 5.010122 0 1 ack 40 ------- 2 0.0.0.0 1.0.1.0 0 3 
D 5.350714118 _2_ RTR CBK 4 tcp 4103 [25c 0 1 800]
D 5.688508990 _2_ RTR CBK 5 tcp 4103 [25c 0 1 800]
D 6.350020368 _2_ RTR CBK 6 tcp 4103 [25c 0 1 800] 
D 7.349560368 _2_ RTR CBK 7 tcp 4103 [25c 0 1 800]
D 8.550160368 _2_ RTR CBK 8 tcp 4103 [25c 0 1 800] 
D 10.949520368 _2_ RTR CBK 9 tcp 4103 [25c 0 1 800] 
D 15.750980368 _2_ RTR CBK 14 tcp 4103 [25c 0 1 800] 
D 25.350220368 _2_ RTR  CBK 15 tcp 4103 [25c 0 1 800]

So please help me!! I have no idea why are the packets dropped and why
does this happen when the packetsize is higher than 4082. Thank you for
your help !!

Best regards,
Erwin Haller