Net360

Jaspal Singh

NETW360, Professor’s Daniel Dronsick

11/18/12

Lab #3, Hidden Node

Lab Report Week 3 Lab: Mixed 11b/11g WLAN Performance

When you answer these questions, include in your answer the name of the statistics panel you used to derive the answer to the question. Remember that each of the panels has a name in the top bar.

( 2. What does Access Point Connectivity statistic collected for the roaming station show?

Answer:- The Access Point Connectivity statistics collected show that the data remains the same. AP Connectivity remained constant throughout the 30 seconds of the simulation.

[pic]

( 3. What do you think the Wireless LAN control traffic received by the roaming 11b node when it is in the Engineering building, is composed of?

Answer: - According to the lab help files it contains random outcomes for the size of generated packets (specified in bytes).

[pic]

( 4. How much did our roaming node reduce the total throughput in our heavily loaded wlan?

Answer: - When the simulation started, throughput was at 25,500,000 bits/sec. At 13 seconds which is when the roaming node entered the engineering building, throughput dropped to about 21,600,000 bits/sec at a loss of 3,900,000 bits/sec. At it left (at around 18 seconds), throughput went up to 25,500,000 bits/sec.

[pic]

( 5. What caused this reduction in “goodput” on the 11g WLAN?

Answer: - The interference of the roaming node most likely caused it as we see the throughput drop when it enters the range of the 11g WLAN

Questions and Addenda

( 6. Supposedly, 802.11b is “backwards compatible” with 802.11g yet this lab demonstrates there are significant problems with allowing the two to coexist. What is the primary “incompatibility” between b and g?

Answer:- Appliances may interfere on the unregulated signal frequency

( 7. There is another mechanism besides RTS/CTS that helps the incompatibility.

Explain...