Can we use ESP-NOW as a wireless communication

ESP-NOW is a connectionless low-power communication protocol defined by Espressif for ESP32. It doesn’t need a router for communication or any Wi-Fi connection. It is a peer-to-peer protocol, and the data doesn’t need to be transmitted through the network layer which means that the communication won’t disturb any other wireless communication. Would this be considered as a qualified protocol for wireless communication or is it still cannot be used since it is not Bluetooth/Zig-B/IF/RFID?
Thank you for your kind consideration.

Hi @tuksidocs ,
thank you for your inquiry.
According to the Espressif website ESP-NOW can work with a Bluetooth LE connection, which is allowed according to Section 3.6 of the OnStage rules.
However we are currently not allowed to use any protocol based on a Wifi connection.
Let me know if that helps.
Best regards

Can you confirm that our team can use ESP-NOW?

We can show that we do not have any WiFi connection in order to communicate between robots. Only MAC Address of the robot (a micro-controller board) needed to be a key to identify a receiving board.

Our team has also researched for ESP-NOW protocol infrastructure and found that it is quite similar to Bluetooth. See the references ESP-NOW user’s guide , Device to Device Communication with ESP-NOW. However, we are not sure that we understand the system clearly and not sure that it is allowed to be used since the name itself is not listed in the rule but we can make sure that our communication will not interfere with other teams’ robots according to Section3.6.

Thank you in advance for your clarification.

Hi @tuksidocs ,

unfortunately both resources you shared above state, that the ESP-NOW model relies on a physical layer according to IEEE 802.11b, which basically is Wifi. It only makes a different approach on how the connection is used to transmit data.

According to Espressifs Website ESP-NOW can also work with Bluetooth LE. If you can find a way to make use of that function, you are free to use it at the competition.

Best regards

From my understanding, when Espressif says that ESP-NOW can work with WiFi and Bluetooth, what they meant is that the microcontroller can support ESP-NOW, WiFi, and Bluetooth concurrently.

ESP-NOW works using management frames of 802.11. Strictly speaking, it is not WiFi as it does not implement WPA, which is a requirement for WiFi.

The bigger concern is whether ESP-NOW can interfere with WiFi. It theoretically can, just like any other devices operating in the ISM band like Bluetooth and Zigbee (both of which are allowed), wireless keyboards and mouse, and many other common devices. Whether any of these can result in any actual impact on WiFi, is questionable. I would opine that you’re far more likely to get interference from an audience member using a phone hotspot to watch youtube.

Considering the low data rate of ESP-NOW, is seems unlikely for it to cause any more issues than other ISM devices. ESP-NOW is also much cheaper and easier to use than the alternatives, which is an important benefit.

Perhaps Robocup should relook at the rules governing wireless communication. If it’s necessary to prevent interference, perhaps reserving part of the ISM band would make more sense.

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