Initialization of per-flow delays uses the normal ipfw and dummynet commands
(see "man ipfw" and "man dummynet") but requires certain options to be chosen.
The following should be executed on each machine to start the per-flow delays.

   sysctl -w net.inet.ip.dummynet.hash_size=256

This command increases the number of available per-flow queues.

   ipfw pipe 1 config delay 0ms mask all

This command installs dummynet pipe 1 with no bandwidth limitation and no
delay (this combination of no bandwidth and 0 delay parameters is what invokes
per-flow delays).  The "mask all" parameter indicates that all bits of the IP
addressing 5-tuple are significant in defining a flow.

   ipfw add 10 pipe 1 ip from <address/subnet> to <address/subnet> out

This command creates firewall rule 10 to pass ip datagrams through pipe
1.  The rule number must be chosen so that it comes first in the set of
rules. The "out" parameter is important because we want to delay only
outbound datagrams and not inbound as well.

   sysctl -w net.inet.ip.dummynet.delay_cdf=0
   sysctl -w net.inet.ip.dummynet.delay_cdf_p1=10
   sysctl -w net.inet.ip.dummynet.delay_cdf_p2=150

These sysctl calls write the values for the min (p1) and max (p2) of the
uniform distribution of delay times in milliseconds.

/sbin/sysctl -w net.inet.ip.dummynet.dn_randseed=<random seed>

This sysctl call writes the value of the random seed that is subsequently
used by the per-flow delays.


To assign delays that are sampled from IMC'03 paper, use:

   sysctl -w net.inet.ip.dummynet.delay_cdf=1