Full-speed 802.11n connection between two laptops without an access point

I have two laptops with 802.11n-capable wireless adapters (Intel WiFi Link 5100 AGN and Atheros AR9285) in them. However, I can't find a way to connect them at a speed higher than 54 Mbps. The methods of connection I've already tried are:
1) an ad hoc connection;
2) Windows 7 Wireless Hosted Network (netsh wlan start hostednetwork);
3) Connectify software;
4) Intel My WiFi software.
In all cases I used WPA2 security. The network is recognized as 802.11n, but the speed is always 54 Mbps only. What can be preventing the connection from using higher speeds? Both laptops run Windows 7 Ultimate.

SlimShaggy

Posted 2011-07-01T20:37:21.947

Reputation: 218

Answers

Finally figured it out. The problem was caused by the Atheros AR9285 adapter - its 802.11n capability was locked, and after using the Atheros EEPROM Tool to unlock it, the connection speed increased to 65 Mbps. The AR9285 can run at 150 Mbps on a 40 Mhz channel though, so if anybody knows how to make a Wireless Hosted Network / software AP use a wide channel, please reply.

SlimShaggy

Posted 2011-07-01T20:37:21.947

Reputation: 218

I know this is old, but I just want to point out that WiFi works in half-duplex, so for a 150 Mbps device, you can send a maximum of 75 Mbps in each direction. 65 Mbps is fairly close to that, and it's normal to be below the max theoretical throughput, especially if there is any other wifi activity in the area. – Nicu Stiurca – 2015-04-20T19:10:09.737

I think that AdHoc is one of those fuzzy areas not covered in the N spec, and may default to B speeds. See if the devices have an extra option for AdHoc in the device settings, some do I have heard.

dbasnett

Posted 2011-07-01T20:37:21.947

Reputation: 459

The Atheros adapter indeed has an "ad hoc 11n" setting, which is enabled. However, the connection variants 2-4 use Infrastructure mode with one of the laptops acting as a software access point, and shouldn't be affected by ad hoc limitations. Still I can only reach G speeds. – SlimShaggy – 2011-07-01T20:53:35.930

If they were the same adapter and had the setting enabled on both you might have some success. – dbasnett – 2011-07-01T21:23:35.340

Well, I can use Infrastructure mode instead of Ad Hoc mode, so the setting becomes irrelevant. Why do I still get 54 Mbps? – SlimShaggy – 2011-07-01T21:31:17.690

I think the answer is an inexpensive N-AP, or wait for the next release of the drivers for the wireless cards and hope that AdHoc has been fixed. – dbasnett – 2011-07-02T16:15:20.820

OK, I'll try to make it clear once again: I have 54 Mbps even when I'm NOT using AdHoc. – SlimShaggy – 2011-07-02T17:41:51.977

Oh, so you have an AP? I missed that. What kind? – dbasnett – 2011-07-02T17:44:55.967

One of the laptops is used as a software AP (a feature of Windows 7 called "wireless hosted network", described here: http://msdn.microsoft.com/en-us/library/dd815243.aspx).

– SlimShaggy – 2011-07-02T22:30:38.270

You might try reading this article:
http://erratasec.blogspot.com/2009/11/windows-7-includes-soft-ap.html

It tells you how to set up a virtual access point on Windows 7 (a "Microsoft Virtual WiFi Miniport Adapter"), so that the two machines will be able to connect using infrastructure mode rather than ad hoc. The short version is enter a command like the following into an elevated command prompt:

netsh wlan set hostednetwork mode=allow ssid=Test key=letmein9

The will give you a new network named "Test" with a password of "letmein9"

Joel Coehoorn

Posted 2011-07-01T20:37:21.947

Reputation: 26 787

I've already tried this, it is listed in my question as the connection method #2. In addition, I've already overcome the 54 Mbps barrier, and am now stuck at 65 Mbps, as stated in my post marked as the accepted answer: http://superuser.com/questions/305188/full-speed-802-11n-connection-between-two-laptops-without-an-access-point/308273#308273.

– SlimShaggy – 2011-07-09T08:20:52.427