Superior detector with ESP8266 and OLED SSD1306
I would like to present a recently created contraption.
I gave it a working name Supervisor detector.
The ESP8266 chip and the SSD1306 OLED display are used here.
I`m in a hurry to explain the principle of operation.
The WIFI network is widely used, we use it at home, at work, in a cafe.
Very often, as I have noticed, people do not turn off WIFI on their phone, either because of laziness or ignorance.
And when phones lose connection to the network, they become quite "talkative" and periodically start desperate attempts to find a known WIFI network to connect to.
They do this by sending packets containing, among others: their MAC address and this feature was used in the presented device.
We have a defined list of MAC addresses in the table that we want to monitor and when one appears within the range of our ESP,
we have signaling in the form of lighting the LED for a few seconds and displaying the name assigned to a given MAC address on the display.
The algorithm is quite primitive, it only signals 1 active device nearby at a time, but it works great for the intended purposes.
The listening library is not my own, a Ricardo Oliveira project called Friend Detector was used here.
https://github.com/RicardoOliveira/FriendDetector
I made changes to adapt the code to my requirements.
It is true that the application is intended to be part of a building automation project and serve other purposes, i.e. after detecting the MAC address we want, it is supposed to turn on the air conditioner in the heating mode using the IR diode before the user even enters the house.
But at the moment I`m testing the system at work and it works great as a supervisor detector
While writing the post, the LED light came on and I was able to prepare for my supervisor`s visit
) (greet him by name without even seeing him yet).I noticed that the system can catch frames at a distance of about 80 m and in a quite radio-polluted industrial environment where a lot of machines work.
The casing is not very beautiful, but it was made quickly to protect the device so that bystanders would not accidentally short circuit it.
I don`t have a diagram because it is a manual connection of the OLED display and LED to the ESP.
Below is a video of the device in operation.
Source codes attached.
Comments
Incredible! Let me tell you, there is a deposit for a device that could be normally sold, for analyzing the presence of people, detecting, and notifying. Of course, it would support a certain number of... [Read more]
A very interesting and clever device. From what I can see on my phone, the MAC address is generated randomly, which may make it difficult to identify the user. [Read more]
Some time ago, 15 years ago, my relative and his friend in the USA had a company that offered billboards and other marketing attention grabbers that scanned the environment for mobile devices with BT enabled.... [Read more]
There could be many problems, including the worst - reservations regarding privacy and the need to obtain prior consent. Although no one cared 15 years ago, so maybe they failed on some technicality. [Read more]
If the "Randomized MAC" function is enabled, there may be a problem with "targeting". In mine it is turned on ;) [Read more]
It seemed to me that the device was scanning for networks. Only when it finds a network saved in itself with the right to establish a connection does it become "talkative". In other words, if a device... [Read more]
What you described is passive scanning. Smartphones perform active scanning by sending a frame cyclically probe request , in which - in addition to your own identifier - there is also a place for a... [Read more]
Otherwise, it would not be possible to connect to a network that has broadcasting disabled. [Read more]
It is worth adding a buzzer to the system. Now you have to constantly watch the display or diode. [Read more]
My observations show that random MAC is for different WiFi networks. If you connected to one network, e.g. at home, the phone will report the same "randomized" MAC address to a specific network. I don`t... [Read more]
This is actually true, otherwise the pool of addresses reserved on the router would increase. And with poor coverage, when the phone would lose and find (new MAC) the network, another IP would be blocked.... [Read more]
If the phone loses coverage, it starts sending probe request frames and when it finds itself in the network coverage again, it is renegotiated on the DHCP server and the same IP address is granted for... [Read more]
If smartphones are not restarted, enabling randomization may not actually be effective. In my opinion, in the name of generally understood security, the smartphone should be restarted once a day. The MAC... [Read more]
I can set any time, I know. But I meant 20 attempts/sec. Unless we know the local MACs, and every stranger is him. [Read more]
I wouldn`t be that optimistic about the supervisor`s skills ;-) )) Depending on age, it`s sometimes good to know where to find the slider to turn WiFi on/off. [Read more]
Most supervisors at some level know quite precisely how much time employees actually work and how much time they spend chatting, browsing the Internet or doing private matters. They just tolerate it for... [Read more]
Thanks for the clarification. I had previously read that the default mode for WiFi is passive mode and I thought this was used on smartphones. While researching the topic, I came across the website ... [Read more]
Do BT wristbands and watches have MAC randomization? BT listening can also provide a lot of information, e.g. BT headphones or even cars. [Read more]
Beautiful block :) Some time ago I looked at the DHCP server logs to check whether the management had reached the plant. By the way, assuming you are on the same Wi-Fi as the president, it would probably... [Read more]