sending and recieving data from esp8266

Question

We're trying to make an network of connected cars in which the status of one car is continuously updated to the nearby cars (for example, speed, gear, brakes, etc.).

Can I continuously send out sensor data via ESP8266 and and any nearby ESP8266 can pick it up? Is it possible? Or if there's any other method?

• dandavis: yes, that's completely possible. you can go ESPNOW or mesh or a pre-setup LAN.

Answer 1

Yes, you can - if all the "cars" are on the same WiFi network.

If that is the case, then I'd recommend using UDP as your transport layer, and either broadcast or multicast the packets.

I use UDP and Multicast to send sensor data from multiple sensors to multiple receivers on my network. All nodes subscribe to the same multicast address, and the sensors include their own ID in the packet to identify them. A sensor sends out one packet, and all the other nodes can receive it.

However, if there is no active WiFi network already established between the "cars" then no, there's not a lot you can do with an ESP8266. It communicates using IP, and that relies on there being an established layer 2 network (WiFi / Ethernet, etc) already in existence. You should instead investigate more peer-to-peer communication technologies, or communication technologies that don't rely on establishing a connection to a network of any form. Maybe the nRF24L01+ would be a better fit?

• dandavis: ESP-NOW fits the problem better than wifi, which has to maintain a connection. ESPNOW also allows encryption (nrf doesn't) and has a nice built-in encoder, with error detection, sender ID, etc.