How to set 5 GHz ad hoc network using a dual band 7260 802.11ac module

[KHugh]

I am trying to set up an ad hoc network under both Windows 7 and Linux with these WiFi cards. However, whilst I can set up an ad hoc network at 2.4 GHz, I have not been able to do so at 5 GHz. There should be no regulatory reasons why I cannot do that in the UK.

Has anyone else been able to set up such an ad hoc network, and if so how?

I am using some Dell rugged laptops with the 7260s running either Windows 7, Ubuntu and Fedora.

[jbenavides]

Hello KesHughes,

Thank you for using the Wireless Networking Forums.

Please elaborate on the process you are using to configure the Ad Hoc network, let us know the application name, version and steps you have followed; the computer model, wireless adapter driver version, and any other information that may help provide accurate recommendations.

[KHugh]

Taking Linux as an initial example, we are running Fedora with a 3.19 kernel and version 12 of the 7260 firmware. I can successfully create a 2.4GHz ad hoc network with the following command line:

iw ibss join

where:

• is the name of the 7260 interface
• is the name of the ad hoc network you want to create or join
• is the frequency of the wifi channel in MHz, e.g. 2412 for channel 1

Note that this only works for wifi channels 1-11 below (consistent with theveterans view above).

If I try to create an ad hoc network at 5 GHz with the following command line:

"iw wlp2s0 ibss join TestNet 5180"

I get an error message:

"command failed: invalid argument (-22)"

I get the same error if I try to set an ad hoc network in channels 12 and 13 at 2.4GHz.

On further investigation, "iw list" tells me:

Frequencies: * 2412 MHz [1] (20.0 dBm) * 2417 MHz [2] (20.0 dBm) * 2422 MHz [3] (20.0 dBm) * 2427 MHz [4] (20.0 dBm) * 2432 MHz [5] (20.0 dBm) * 2437 MHz [6] (20.0 dBm) * 2442 MHz [7] (20.0 dBm) * 2447 MHz [8] (20.0 dBm) * 2452 MHz [9] (20.0 dBm) * 2457 MHz [10] (20.0 dBm) * 2462 MHz [11] (20.0 dBm) * 2467 MHz [12] (20.0 dBm) (no IR) * 2472 MHz [13] (20.0 dBm) (no IR)

and....

Frequencies: * 5180 MHz [36] (20.0 dBm) (no IR) * 5200 MHz [40] (20.0 dBm) (no IR) * 5220 MHz [44] (20.0 dBm) (no IR) * 5240 MHz [48] (20.0 dBm) (no IR) * 5260 MHz [52] (20.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5280 MHz [56] (20.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5300 MHz [60] (20.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5320 MHz [64] (20.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5500 MHz [100] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5520 MHz [104] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5540 MHz [108] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5560 MHz [112] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5580 MHz [116] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5600 MHz [120] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5620 MHz [124] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5640 MHz [128] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5660 MHz [132] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5680 MHz [136] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5700 MHz [140] (22.0 dBm) (no IR, radar detection) DFS state: usable (for 514715 sec) * 5720 MHz [144] (disabled) * 5745 MHz [149] (disabled) * 5765 MHz [153] (disabled) * 5785 MHz [157] (disabled) * 5805 MHz [161] (disabled) * 5825 MHz [165] (disabled)

All the available 5GHz channels are listed as "no IR" which means that the device is not allowed to initiate a transmission without first being told it is allowed to do so by, say, an access point. AFAIK this is what prohibits the device from creating an ad hoc network in a 5GHz channel.

But "iw reg get" tells me that:

country GB: DFS-ETSI

(2402 - 2482 @ 40), (N/A, 20)

(5170 - 5250 @ 80), (N/A, 20)

(5250 - 5330 @ 80), (N/A, 20), DFS

(5490 - 5710 @ 160), (...

[John_S_Intel]

Have you tried posting your question/issue on the Linux wireless support site? https://wireless.wiki.kernel.org/en/users/support https://wireless.wiki.kernel.org/en/users/support

[jbenavides]

Hello KesHughes,

Intel Wireless Adapters only support Ad Hoc networks in 2.4 GHz due to regulatory limitations. Ad Hoc in 5 GHz is not available in order to comply with these regulations.

[KHugh]

Thanks for the answer Jonathan_intel. It seems a shame that Intel block operation of ad hoc mode at 5GHz because AFAIK there are no regulatory constraints of operating an ad hoc network at 5GHz in the UK. We have been able to do just that with other adapters. What I think the adapters (or the underlying platform) need to be able to do in some of the 5GHz channels is perform dynamic frequency selection (DFS) to allow wifi networks and radar to coexist. However, in channels 36-52 (5170-5250 MHz) there is not a requirement for DFS. Hence even if the adapter does not implement DFS it should still be able to set an ad hoc network in those channels.

Could you confirm whether this assessment is true and whether this is likely to persist for future Intel wifi products?

[jbenavides]

Hello KesHughes, we will check further on your inquiry and will contact you as soon as we have the details.

[MHaun]

Was an answer ever provided for this? I have the exact same question.

The "no IR" (cannot initiate radiation) limit on 5 GHz is clearly not needed for regulatory compliance, in many of the markets this device is sold into---most notably the United States. So the question is really twofold, (1) Was this intentional? and (2) Can anything be done about it? apart from switching to another wireless card.

Thanks in advance for not letting this one fall into the cracks (:

[tvete]

Not possible due to AdHoc channel being selectable from 1-11 only. You need a Non-Intel card for that such as ASUS PCIE AC68 wlan card

[BChes1]

Would also like to add that I am disappointed to not be able to use Intel cards the way I use competitor cards in conjunction with hostapd-- iw list output in Linux makes for a lacklustre outcome. --The cards have great support as a client device, don't get me wrong. But not having master mode available in linux (that allows me to spin up an AP on demand) is why I've been buying cards from your competitors...

[jbenavides]

Hello,

The Intel® Dual Band Wireless-AC 7260 and other current Intel wireless adapters are designed to be used as WiFi clients and for basic Ad Hoc usage.

They don't support Ad Hoc networks in 5 GHz, and they are not designed to be used in Access Points (hotspots).

We appreciate your feedback and comments regarding this topic, and will forward it to the proper resources so it can be considered in the future.

[MHaun]

While I acknowledge Intel's right to enable/disable features as they see fit, I have to say, "designed to be used as WiFi clients" sounds awfully like code words for "intentionally crippled to support our market segmentation strategy." (Unless there is some deep technical reason why the bit sequences in AP packets require different hardware than the bit sequences in client packets?) Companies do this all the time, of course, but as certain of your competitors in the wireless space are not doing it, I hope you can understand why this will push many of us away.

[jbenavides]

Hello,

We understand your concern, and you can be sure we take your comments and recommendations into consideration. Your feedback is very important as it helps us understand the needs of our customers.

Please understand that Intel® Wi-Fi Products are designed according to international standards and regulations, since they are integrated in systems from different manufacturers all over the world. For this reason, some features, like the one mentioned in this forum are not supported by these adapters.

[DFitz4]

Hi,

Is there any more update on this?

From what I understand, the theoretical max for thie AC 7260 is 867 Mbps (i have the 2 antenna version). Practically you should expect half this datarate.

Now, I'm pretty sure this requires the 5GHz enabled to achieve these speeds. I purchased these adapters for a project point to point (ie: setting them up to communicate directly with each other).

From the above it appears that I can't do this with an AD-Hoc network - is this correct?

What other mode can I run them in as point to point devices to get the ADVERTISED speed. Otherwise this is just false advertising.

thanks

Daniel

[BArch]

Hi jonathan_intel,

Could you please provide the up to date status regarding this issue described above?

I have the identical issue as define in comment " KesHughes Feb 24, 2015 6:02 AM (/message/280879# 280879 in response to jonathan_intel)".

I have following cards on my device:

1- Intel Wireless N 7260

2- Intel Dual Band Wireless AC 7260

I appreciate you time and if anyone else has a work around and/or other ideas regarding this issue please leave a comment.

Cheers,

Archer

[jbenavides]

Hello,

Ad hoc mode using 5 GHz is not supported by Intel® Wireless Adapters, since the adapter must comply with standards and regulations for international use.

The Linux drivers are part of the upstream Linux* kernel and are available through the regular channels, distributions, or the Linux* kernel archives. You might want to check the https://wireless.wiki.kernel.org/en/users/support Linux Wireless Support about this as well.

[idata]

Hello，

Can you tell me how to use ad hoc mode in 2.4GHz?

I use ubuntu 14.04 and intel 7260HMW.

iw ibss join ---is not useful.

Thank you very much.

[ASouz7]

ChangeS,

As informed before, please contact https://wireless.wiki.kernel.org/en/users/support Linux Wireless Support for additional support as they handle Linux* support for this adapter.

Best regard,

Aleki