Description: 
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dosdbell creates a compact dumbell topology using a distribution of 
hops specified as probability density function (pdf). 
The parameters of the topology are inputed from a file. 

Input:
----- 
The parameters of the attack tree are specified in the following
format. Link bandwidth is specified in Mbps, delays are in ms,
and starttime in seconds. 

diameter bn_bw bn_delay	         
TCP_src, link_bw starttime  	 
attackers rate packet_size Master starttime 
finishtime  

File Explanation:
Line 1: Maximum number of hops, bandwidth(Mbps) and delay(ms) for the bottleneck  
Line 2: Background traffic paramaters: 
        Number of TCP source, link_bw(Mbps) and all TCP sources start by starttime(in sec)
Line 3: Attack traffic  parameters: 
	Number of attackers, attack rate, packet size, presence/Absence of master, and 
	time(in sec) at which the attack starts.  
Line 4: Simulation termination time (in sec) 

The Master variable is a boolean value to indicate presence/absence (1/0) of 
a master. If a master is present, then an additional delay component
due to the trigger mechanism is added. 
The model assumes all hops have the same propagation delay(specified as bn_delay).
We use TCP Reno (oneway) to model background traffic.

For example:
25 10 20        # Maximum number of hops between two nodes in the original topology is 25, 
                # bottleneck bandwidth is 10Mbps, propagation delay is 20ms 
100 0.1  20     # Hundred TCP sources each send at 100Kbps, all start before 20s
200 0.05 200 0 50 # 200 Attackers, each send at 50Kbps using 200B packets,
		   no master. The attack starts at 50s
150		 # Simulation ends at 150s 


Output:
------
Creates a tcl file with the ns topology that can be used 
directly to run the simulation. 
The simulation creates a queue trace file, qtrace.tr, at the bottle neck link. 



Usage:
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dosdbell input_parameters output_tclfile
