ESP8266 Community Forum

ESP8266 AP with a hidden SSID is very hard, nearly hardly, to be connected by other STAs.

We tried many SDKs including lastest 3.x, found that, if we set the esp8266 into ap or sta+ap mode with an hidden SSID, other STA is very hard to connect the AP suucessfully, often give response "+CWJAP:3" for an example if using another esp8266 module to connect it. Very occationally it would succeed.

If we enable the wifi event callback by wifi_set_event_handler_cb() in th ap module and check the
switch (evt->event)
case EVENT_SOFTAPMODE_PROBEREQRECVED
Once the other stas is trying to connect the AP, there is expected log-print under the event.


What might be the cause, and how to locate and fix?

Thanks!

Some expert would help with guideline?

Thanks !

Yeah, don't use hidden SSID's. The only difference between a "normal" and a "hidden" SSID is that the "SSID name" field in the beacon (which is normally sent every 100 ms) is filled with the null string. So it won't hide anything, WLAN can't work without these beacons, so your SSID will be seen by anyone anyway. It may not show up in the usual "associate" menu from your telephone, but a wifi scanner app will show it.

Hidden SSID's are a pain and have no real advantages. Don't use it.