Wi-Fi Protected Setup (WPS) Issues

Microchip TCP/IP Stack

Microchip TCP/IP Stack Help
Wi-Fi Protected Setup (WPS) Issues

Wi-Fi Protected Setup (WPS) security connection mode is only supported by MLA v5.42 July 2012 releases or later. 

 

  • Why is MRF24WG0M reporting error message "Event: Connection Failed : WF_RECV_DISASSOC : WF_UNSPECIFIED" when trying to connect to certain AP/routers in WPS-PBC security connection modes ?

When running WiFi TCP/IP Demo, the output display shows 

*** WiFi TCP/IP Demo *** 

Start WiFi Connect 

Domain: FCC 

MAC: 00 1E C0 08 F1 04 

SSID: (none) 

Network Type: Infrastructure (using WPS Push Button) 

Scan Type: Active Scan 

Channel List: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 

Retry Count: Retry Forever 

Beacon Timeout: 40 

Security: WPS push button method 

Power Save: Disabled 

 

New IP Address: 169.254.1.1 

Event: Connection Failed : WF_RECV_DISASSOC : WF_UNSPECIFIED 

 

A wireless capture revealed that some AP/routers is transmitting disassociation frames instead of deauthentication frames during WPS process. This behavior is not according to 802.11 specifications and thereby causing WPS to dysfunction. RF module FW (from 0x3108 onwards) was modified to handle this erroneous case. 

 

  • Why is the AP/router, in WPS mode, taking a longer time to connect, as compared to when AP/router is in WPA/WPA2 security mode?

Refer to Wi-Fi Protected Setup Specification Version 1.0h standard. 

WPS protocol is built on top of the WPA/WPA2 EAPOL 4-way handshaking process and there are additional process for WPS. Time allowed for entire WPS protocol is 2 min. 

The specifications listed the below parameters

  1. Retransmission timeout = 5 sec
  2. Individual message processing timeout = 15 sec
  3. Overall timeout for entire protocol to complete = 2 min

 

  • What is needed to see the WPS frame exchanges in a wireless sniffer capture?

Either click on <Protocol> field and scroll down until this starts with the alphabet "E..." or in the <Filter:> field, type in "eapol". 

 

  • What is special about the PIN selected for WPS-PIN? Can this PIN be randomly selected by the user?

The 8 digit PIN is NOT randomly generated. The last digit is the checksum of first 7 digits of the PIN. If this checksum is wrong, MRF24WG0M module will reject this PIN code. 

 

  • I just bought a brand new AP and have problems using WPS to connect to MRF24WG0M.

It has come to our attention that there are some AP/routers that do not work out of the box using WPS feature. These AP/routers may still require some minimum set up, such as setting up security to WPA2-Personal, etc. Please refer to their instruction manuals for more details in WPS setup.

Microchip TCP/IP Stack 5.42.08 - June 15, 2013
Copyright © 2012 Microchip Technology, Inc.  All rights reserved.