Understanding TCP/IP Model Internals and Interfaces
Understanding TCP/IP Model Internals and Interfaces
Understanding TCP/IP Model Internals and Interfaces
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1508 <strong>Underst<strong>and</strong>ing</strong> <strong>TCP</strong>/<strong>IP</strong> <strong>Model</strong> <strong>Internals</strong> <strong>and</strong> <strong>Interfaces</strong><br />
2. At what event did the other side send a FIN segment? ___________<br />
3. At what event was the connection finally closed on the client? ___________<br />
4. At what event was the connection finally closed on the server? ___________<br />
5. Click on Close to close the Simulation Execution window.<br />
END OF LAB 1<br />
Examine Congestion Window (Homework Lab)<br />
We want to determine the final congestion window on the server side before the session was closed.<br />
In step 4 above, we hope you determined that the connection was finally closed at event 458.<br />
Let’s run the simulation again, stop the simulation just before this event <strong>and</strong> print the congestion<br />
window.<br />
Recall that congestion window is printed from the diagnostic block of tcp_conn_v3.pr.m, so in order<br />
to print the state we will need to get the process model ID of tcp_conn_v3.pr.m on the server.<br />
1. Run the simulation in the ODB again following steps 1-2 from the section Run the Simulation<br />
in ODB above. Again, click on the Console tab if you do not see the console.<br />
2. Stop the simulation at event 458:<br />
a. Type evstop 458 in the simulation console window <strong>and</strong> press the Enter key. This will set a<br />
breakpoint to stop the simulation before event 458 is executed.<br />
b. Type cont in the simulation console window <strong>and</strong> press the Enter key to run the simulation<br />
until the above breakpoint is reached. Alternatively, you may click on the Continue button.<br />
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