SE 14-428: Advanced Computer Networks
Semester Project: Experimental Setup
Michael J. May
Semester 1 5777
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Experimental Setup
Once you have a good background on the protocol that you’ll be measuring, you can develop a testing and
measurement setup to evaluate it. Each protocol is different, but there will likely be many different ways to
do the testing or measurement. You must make fundamental decisions such as:
1. What network topology and connectivity model to use
2. Whether to use physical nodes or virtual nodes
3. Whether to use an emulated environment
4. How to gather data from the experiment
The last decision (how to do measurements) is heavily influenced by the first three items. For instance,
some emulated environments have built-in measurement capabilities while others let you use general purpose
measurement tools (ex. Wireshark).
The material in the literature review should have given enough background to get started with designing
a measurement setup. Since this may be the first time you are doing a networking experiment, it would be
a good idea to take lessons from experiments that others have previously performed. In particular, if you
find a measurement setup in an academic paper or article, use it as a starting point to design your own
experiment. Modeling your experiment on previous work will also make it easier to compare your results
with other’s in the project report (the following phase).
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Experimental Hypothesis
You must formulate a one to three (1-3) sentence hypothesis for the experiment. The hypothesis must state
what you intend to measure or evaluate about the protocol in your experiment. The hypothesis should
include a claim about the results of the experiment as well. Some sample hypotheses:
TCP’s New Reno congestion control algorithm responds better to packet burst errors than the
Vegas congestion control algorithm
When using Random Early Detection (RED) on a router with three active flows and moderate
load, a setting of M axP < 0.01 gives better results than M axP ≥ 0.01.
Your hypothesis will drive the design of the experimental setup and measurement strategy.
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Figure 1: Sample topology figures
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Experimental Testbed Design
You must plan the topology for your experimental testbed and how you will do your measurements. The
topology you choose is heavily influenced by the particular protocol you are analyzing and the equipment or
emulation tools available. It will be useful to look at previous analyses of the protocol you choose to learn
what are reasonable experimental network topologies.
The main result of your design will be a figure depicting the network topology to be used. To give
you an idea of how the figure should look, two sample figures are shown in Figure 1. You can find many
other examples on line and in academic research papers. Your topology figure must show the nodes in your
testbed, including their names, roles, and IP addresses as necessary and appropriate. If some information
can’t be shown in the figure due to space or readability problems, include the omitted information in the
figure documentation table.
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Figure Documentation
Each node in the figure must be documented in a table with the following information:
• The node’s name and its task
• The node’s attributes (ex. size, bandwidth, memory capacity, port, etc.)
• Whether the node will be physical, virtual, or emulated
• Any node information which was omitted from the figure
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Experimental Measurement Strategy and Tool Documentation
In addition to the network testbed figure and documentation, explain what the experiment will measure and
how the data will be measured. List the data items, messages, or timing values that you will measure. Also
explain which libraries, code, or emulators you will use for the experiment.
If you choose a library or protocol implementation which are not mentioned in the literature review
(previous phase), update the literature review to include them. Don’t worry if the addition makes the
review a bit longer than the upper word limit.
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What to turn in by 15 January 2017
Turn in the following items by the due date:
1. A single PDF file with the hypothesis, experimental testbed figure, the figure’s documentation, and
details of the experiment’s measurement strategy.
• Experimental Setup: 40%
• Hypothesis: 20%
• Testbed design and documentation: 40%
2. A revised version of the literature review from the previous phase as a single PDF file. If the literature
review doesn’t need to be revised, just include it again unchanged.
3. A README file with the names of the students and an estimate of the number of hours spent on the
phase broken down by the names of the students.
Turn in the above in a single ZIP file via Moodle. Each student on the team must submit a copy of
the work by the due date.
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