ESP8266 Community Forum

- Sat Dec 17, 2016 6:08 pm #59619 Using Wi-Fi chips in the standard ieee 802.11 way requires a network but theoretically we could use the physical chips in a different way.

802.11 wasn't designed for simple M2M commands.

I'm proposing an alternative standard should be established that would benefit M2M communication.

Using Wi-Fi chips as opposed to some other radio chip has the advantage of being widely available and cheap.

- Sat Dec 17, 2016 10:33 pm #59624 The esp8266 sdk mentions the function:
wifi_send_pkt_freedom
Function:
Send user-defined 802.11 packets
Notes:
• Can send: unencrypted data packet, unencrypted beacon/probe req/probe resp.

Is this basically what im looking for?

If I construct an 802.11 data packet correctly should this let me just send data from one device to another without establishing a network?

My programming skills are not that great..
Thanks

- Sat Dec 17, 2016 10:52 pm #59625 I think you are wrongly getting hung up on the establishing a network part. All that it is doing is making sure that you don't have to deal with all the rest of the wifi traffic in the area. Just think what you will have to deal with if you heard everything and not just what you were sending. How are you going to filter it all out? That is what the network id does. It only lets you hear data from your devices. Just think of it as a preamble to your packets and conveniently it gets stripped out of the data stream you see. You just get the data.

Now if you want to use the modules as just hardware, and not make use of the structure provided. You can't. You do not have the required information of how the module works. Expressif only provides limited information on the hardware. They give you function calls but they have a lot of code underneath that you have no clue of what it is doing with the hardware. This is not an open architecture. This is not like working with a regular cpu where the manufacture gives you all the details.

And as I said, you are missing the point on the network stuff. What you should be interested in is sending and receiving the data you want. And accomplishing it as easy as possible.

If I construct an 802.11 data packet correctly should this let me just send data from one device to another without establishing a network?

No.

- Sat Dec 17, 2016 11:03 pm #59627 My tests have shown that once i have a connection im able to communicate over longer distances than establishing a connection.

The logical conclusion is that the 802.11 connection protocal is harder to accomplish with faint reception.

The protocal requires a series of back and forth which wont work with faint reception.

The function i mentioned above seems to allow you to send raw 802.11 packets, hence i should be able to send a message without any connection.

Thanks