-[2022-09-13: Parts Research](README.md#2022-09-14-parts-research)
-[2022-09-14: Parts Research](README.md#2022-09-14-parts-research)
-[2022-09-14: Quick note about our traffic monitoring method](README.md#2022-09-14-quick-note-about-our-traffic-monitoring-method)
## 2022-09-13: Post-Meeting Notes
We just talked with our mentor TA about our initial block diagram, high-level and subsystem requirements, and about some of the parts that we are planning on using for the project. She had some great suggestions for us that we think would benefit our project, especially since she had a very similar project when she took the course. \
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@@ -31,3 +32,16 @@ Now that we kind of have our project idea fleshed out, we need to create an init
- The ESP32 series of SoCs all use 3.3 volts as their operating voltage. Since all USB types generally operating at or above 5 volts, we need to drop the voltage down. The AP2112 is a tried and true voltage regulator for 3.3 volts, so we'll use it in our design, too.
- It's very important to keep the battery from overcharging. This battery charge controller appears to be very popular with other boards that are based on ESP32.
## 2022-09-14: Quick note about our traffic monitoring method
So when our team initially talked about this idea, we were certain that we would need to purchase a separate Wi-Fi module to scan both bands of the 802.11 spectrum (2.4 GHz and 5 GHz). However, after a bit of research, and because of a hardware limitation of the ESP32 platform (as of 2022-09-14), we found that only scanning the 2.4 GHz frequency may be sufficient. This is because most Wi-Fi devices send probe requests after a certain event or a certain amount of time, which is dependent on the operating system used by the probing device. These probe requests are sent on both the 2.4 GHz and 5 GHz bands, since not all Wi-Fi networks utilize the 5 GHz band.
The discovery phase of a Wi-Fi connection can be broken down to the following steps:
1. Wi-Fi client sends a (periodic) probe request to its general viscinity.
2. All Wi-Fi access points (APs) that have read the probe request frame generate and send a probe response to the client (unless the AP is configured otherwise).
3. Wi-Fi client received the probe response from the responding APs to generate the list of available Wi-Fi connections.
Here are some good references to take a look at to learn more:
-[What are Passive and Active Scanning? - Wi-Fi Alliance](https://www.wi-fi.org/knowledge-center/faq/what-are-passive-and-active-scanning)
-[802.11 MAC Series – Basics of MAC Architecture – Part 3 of 3 - CWNP](https://www.cwnp.com/802.11-mac-series-ndash-basics-mac-architecture-ndash-part-3/)
-[Oliveira et al. 2019](https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=8747391)
