Sounds more like bluetooth.

bluetooth have 10m distance, wifi 100m or km if You have good antena in mesh network this is important.

BTW bT still need negotiation time.

https://www.youtube.com/watch?v=yCLb2eItDyE 10km in wifi, usualy 100m not 10m

> How to send a message when the wifi devices only pass each other for a few or a few tens of seconds for example.

I took that to mean pretty close.

There was a standard called Wi-Fi Direct for such a use case. I remember evaluating it for a automotive project (where cars would pass object only for a short time). Maybe it’s fits your use case.

https://en.m.wikipedia.org/wiki/Wi-Fi_Direct

wifi direct have transmiter and receiver too ;) In my opinion sending message like walkie-talkie radio protocol is different. (for example https://github.com/ntoivola/uvk5-chirp-driver-nunu )

Look this https://github.com/br101/libuwifi

RFID has some of the significant properties you are looking for. I don't know if it has all of them because I've just about exhausted all my knowledge of RFID and don't know any details of the actual problem you are trying to solve. But RFID is deployed at scale and "everywhere." Probably because the technology doesn't depend on protocols developed for other uses (e.g. IP). Good luck.

RFID have small distance yes BT and RFID is ok but wifi im more popular and long working distance

Do you want to be able to continue to use your WiFi device(s) for their normal behavior in the meantime? i.e. is it acceptable if you need to disconnect from WiFi before initiating a p2p transfer?

Directly sending and receiving data over WiFi sounds like a fascinating project! It's amazing how WiFi tech can be repurposed for direct communication without intermediaries. Has anyone experimented with this for IoT devices or local network games? I'd love to hear about real-world applications or any unexpected challenges. Also, how does this approach compare in terms of speed and reliability with traditional methods like Bluetooth or Zigbee? Let's dive into the technical nitty-gritty!

You ask about sendin morse code trought wifi using normal wifi card/modem? Interesting idea. Meybe exist any root usb dongle wifi card. But I dont know any models.

I think there is a defined wifi mesh standard, 802.11s https://en.wikipedia.org/wiki/IEEE_802.11s

I think it was used by the deployed OLPC (One Laptop Per Child) project back in the 90s/early 2000s, which wanted to send them to areas with no internet.

If you can get such a network set up, you should be able to route IP packets over it as normal?

I think during the Hong Kong protests, they also used peer to peer smartphone meshes over either Wifi or Bluetooth (can't remember). Might be worth looking into?

I don’t understand why this is desirable. May I ask what use-case you’re referring envisioning?