WiFiAnalyzer

implemented in Kali Linux

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Brouno Kokthi

Evangelos Pipilikas

Myrto Chatzivoukoudi

About the project

This is the project for the cource Wireless Network and Mobile Communication at AUEB for the year 2021-2022. The main concept of this project is to find the best channel according to the load of every channel.

Tools and libraries

• Airmon-ng
• Iwconfig
• Airodump-ng
• Scapy python3
• Crontab

File compilation

>!< Please make sure you run the script in Kali Linux environment and your wifi adapter supports MONITOR MODE. >!<

1. Open the command line and set the directory to the one that contains the project
2. Use the airmon-ng tool to change the wifi interface from Managed mode to Monitor mode. This can be accomplished by running the command airmon-ng start wlan0
3. Add the rules in the crontab file according to the time you want the script to be triggered. For example the rule 0 20 * * * cd /project && ./script.sh triggers the script at 20:00.
4. Alternate option: instead of adding rules in crontab file, you can change the directory and run the command ./script.sh.

Algorithm basic steps

Step 1: Capture all the beacon frames from access points and save them in a .csv file. (File: wifi_scanner.py)

Step 2: Capture all the data frames from every network that we have already captured in Step 1. Save this information in a .csv file. (File: wifi_data_sniffer.py)

Step 3: Process all the imformation given from step 1 and 2. (File: evaluator.py)

Step 4: Create an algorithm consisting of two parts: channel evaluator and neighbor channel evaluator. (File: evaluator.py)

Step 5: Keep history log for every channel. (File: evaluator.py)

Explaining the algorithm

Channel evaluator

Keep in mind that we have the following information for each channel:

• Percentage of packets comparing to the other channels (packets)
• Percentage of networks comparing to the other channels (networks)
• Percentage of stations comparing to the other channels (stations)

The formula we use to evaluate every channel is:

channel_evaluator = 0.45 * packets + 0.35 * networks + 0.20 * stations

Neighboring channel evaluator

Having every channel's evaluation, next step is check if there is any interference from the neighboring channels.

The information we need here for each channel is:

• Channel evaluation (channel_i)
• Previous channel evaluation (channel_i-1)
• Next channel evaluation (channel_i+1)

The formula we use to evaluate every channel is:

channel_{neighevaluator} = 0.7 ∗ channel_i + 0.3 ∗ (0.5 ∗ channel_i−1 + 0.5 ∗ channel_i+1)

History log

Automatization takes place three times per day, each of which we keep a history log.

Time	History log file name
12:00	morning_measurements.txt
16:00	noon_measurements.txt
20:00	night_measurements.txt

Every time that arrives the time to take the measurements:

1. Take the new data from the scanning (evaluations_new)
2. Load the old data from the corresponding history log file (evaluations_old)
3. Write the new history log back to the corresponding history log file following the formula below:

history_evaluations = 0.8 * evaluations_new + 0.2 * evaluations_old

Code demonstration

For a quick demonstration of the script and algorithm, check the demonstration_ENG.pdf file.