WPS connectivity problem

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Joined: Wed Jan 27, 2016 7:39 pm

WPS connectivity problem

Postby arborwoods5 » Thu Jan 28, 2016 11:25 am


I'm trying WPS test with several types of Wi-Fi APs by using WPS API of NONOS-SDK_V1.5.1_16_01_08.
It works well with certain APs, but with some APs, API returns timeout callback (WPS_CB_ST_TIMEOUT) or failed callback (WPS_CB_ST_FAILED).

Please refer the following cases.
(Case 1 and case 2 are tested with different APs.)

[Case 1:]
Some AP doesn't return the correct response of "EAPoL start" frame, AP sends "EAPoL WPA Key1" frame instead of "EAP Request/Identity" frame.
WPS negotiation doesn't proceed and API returns timeout callback. I had confirmed the AP surely transitioned to WPS mode by the WPS-button operation, and WPS negotiation of wpa_supplicant worked normally with same AP.
I checked ESP's "Association request" frame with Wi-Fi packet capture, it contains "RSN Information" tag, but wpa_supplicant's frame doesn't contain that tag.
So, I suspect this AP doesn’t ignore that tag and transitions to WPA authentication mode instead of WPS negotiation mode.

[Case 2:]
API returns failed callback after receiving “EAP WPS M2” frame from certain AP.
In WPS successful case, the size of “EAP WPS M2” frame is smaller than size of the frame in failure case.

Frame size example:
WPS successful case: 447 bytes
WPS failure case: 504 bytes
Both frames contain same types of parameters, and the difference of frame size is mostly caused by manufacturer information (e.g. manufacturer name, model name, etc.).

So, I suspect the size of "EAP WPS M2" frame is cause of this failure.
(Is there any limitation of buffer size for WPS process?)

The question: is there any solution to solve those two problems?

Posts: 1615
Joined: Mon Oct 27, 2014 11:08 am

Re: WPS connectivity problem

Postby ESP_Faye » Tue Mar 01, 2016 9:21 pm


Can you provide more details about your router, and the setting of your router ?

We will test it using the same router with the same setting.

Posts: 19
Joined: Thu Nov 24, 2016 6:24 am

Re: WPS connectivity problem

Postby gjump » Tue Nov 29, 2016 7:09 am

@ESP_Faye @arborwoods5
Any updates on this issue?
I'm facing the same problem, WPS fails on some routers.
I'm posting on viewtopic.php?f=7&t=3129

Posts: 4
Joined: Sat Jul 22, 2017 7:59 pm

Re: WPS connectivity problem

Postby dalbert » Sat Jul 22, 2017 8:06 pm

In case it provides more clues, the WPS function seems to work reliably with older 802.11n access points (Trendnet TEW-652, Belkin N300), but fails reliably with 802.11ac access points (AT&T/Pace 5268AC and Asus TM-AC1900).

I am using Arduino/EPS8266 core version 2.3.0 which uses SDK version: 1.5.3(aec24ac9)

The failure is always the same; it finds the access point, showing it's SSID correctly but fails to successfully process the public key provided by the access point and acquire the PSK (see trace below).

wps scan
build public key start
build public key finish
f r0, wps discover [ATT4PcDe8QR]
WPS: neg start
f r0, scandone
state: 0 -> 2 (b0)
state: 2 -> 3 (0)
state: 3 -> 5 (10)
add 0
aid 4
process pubkey start
wps: ignore overlap identifier
wps: ignore overlap identifier
wps: ignore overlap identifier
wps: ignore overlap identifier
wps: ignore overlap identifier
wps: ignore overlap identifier
state: 5 -> 2 (17c0)

Has anyone been able to connect to an 802.11ac access point using WPS and if so, can you share details (model #, anything special you had to do in the code)? Thanks!

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