I've been testing the Centrino chipset as an AP via Microsoft's Wireless Hosted Network API (for details on the API, see http://msdn.microsoft.com/en-us/library/windows/desktop/dd815243(v=vs.85).aspx About the Wireless Hosted Network).
The problem that I'm having is that the http://msdn.microsoft.com/en-us/library/windows/desktop/dd439493(v=vs.85).aspx WlanHostedNetworkQueryStatus function fails consistently with error 5023 - ERROR_INVALID_STATE when I have the adapter configured in 802.11a mode via Device Manager -> Properties -> Advanced -> Wireless Mode = "1. 802.11a". This does not happen when the adapter is configured to b/g, a/b/g, or a/g modes.
I suspect that this is a problem caused by the hosted network running on an 11a channel, which is what I am trying to accomplish. In any of the other modes (b/g, a/b/g, or a/g), a 11b channel is picked and the problem does not happen. Also, this problem doesn't happen on the Broadcom and Atheros chipsets I've tested, so it seems to be a problem in the Centrino driver. 6235
You can reproduce this completely with the following steps:
I've tested this on the following chipsets and the issue happens consistently on all of them:
I've also tested this on the following driver versions and the issue happens consistently on all of them:
Could someone from the Centrino driver team see if this is a fixable problem? It prevents us from recommending Centrino laptops to our customers who want to use their laptop as an 802.11a hotspot.
Thanks in advance for any help!
I am also having this problem when trying to use Intel Wi-Fi cards as a soft-AccessPoint when configured in 802.11a only mode (5 GHz)
I have tried the following cards with the latest drivers Wireless_17.1.0_De164.exe using a fully patched Windows 8.1 Pro 64-bit o/s:
All are dual-band cards. All operate correctly as a soft-AP in 802.11b, 802.11g or 802.11n modes (2.4 GHz), but none in 802.11a only mode (5 GHz).
The cards are capable of operating as a soft-AP at 5 GHz as if I configure into 802.11 a/b/g/n mode, and then manually attach as a client to a 5 GHz Wi-Fi network, then the card will operate as a 5 GHz soft-AccessPoint correctly.
Please allow us more time to investigate this further.
As far as I could see trying to replicate this issue, the wireless adapter can only broadcast in the 2.4 GHz band (channel 6, the same as the router); so, dh29 how did you accomplish this?The cards are capable of operating as a soft-AP at 5 GHz as if I configure into 802.11 a/b/g/n mode, and then manually attach as a client to a 5 GHz Wi-Fi network, then the card will operate as a 5 GHz soft-AccessPoint correctly.
My understanding of dual-band cards acting as soft-AP is that the band that they operate on as a soft-AP is the same band that the card is on as a client. [This raises the question of what band does the soft-AP operate on if the WLAN card is not connected to any network? The answer to this appears to be that the card always generates a 2.4 GHz soft-AP if it is not connected to a Wi-Fi network.]
In other words:
I must stae that I am not an expert in the area of Windows7/8/8.1 generation of a soft-AP using a mini-PCIe WLAN card. The above statements are from a bit of information from Microsoft, and some pratical tests.
To answer your question of how did I get the card acting as a 5 GHz soft-AP:
Back to the original problem.... If I have the Intel WLAN card configured in 802.11a mode (i.e. 5 GHz ONLY) then following the same procedure above, fails at Step (4) !!
Setting the adapter's Preferred Band to 5 GHz makes no difference to the band that the soft-AP is started on. My understanding of the Preferred Band setting is used when 2.4 GHz & 5 GHz networks with the same SSID can be seen - in this case 5 GHz would be the preferred choice. My problem is that I cannot start a 5 GHz soft-AP when there are no other Wi-Fi networks.
Just to clarify...
I'm not an Intel rep but I can assure you that it is NOT a bug. When you select the 802.11a mode, the adapter turns off the 2.4 GHz band. Intel had configured to not use the 5 GHz frequence for wireless hosted networks as part of the FCC regulation. As such you can't set a hosted network when the 2.4 GHz radio is off. However, you can change the channel of the hosted network on the Ad hoc channel 802.11 b/g setting in device manager. You can purchase a non-FCC regulated card such as the ASUS PCIE cards that allows you to not only use 5 GHz band but also select DFS channels as the channel for your hosted network.
Thanks 'theveterans'. I suspected as much, but wanted confirmation from Intel so that I can definitively state in our product design meeting that a soft-AP is not possible when in 802.11a only mode.
I also had a support request into Intel's 'official' support channel asking the same question. So far that has resulted in an Intel 'support' person constantly asking about the manufacturer of the PC I am using or whether I'm using Win7 or Win8. Not exactly relevant when it seems the adapter is doing what it was designed to do. I can't understand why it takes Intel so long to state the facts about its own products!!!
Thanks again 'theveterans'.
This is not a bug and it is not possible to accomplish unless the wireless adapter is setup as described in post number 4 while it is connected to a 5 GHz AP.