Re: Peer-to-peer Wifi ad-hoc

[Paul Gardner-Stephen]

No. You must root your phone, and even then many modern handsets need a new kernel to allow ad-hoc Wi-Fi.

The lack of ad-hoc Wi-Fi was reported back in January 2008 as bug #82, and is currently the 3rd most starred issue in the Android issue tracker, and is the oldest open bug referring to a meaningful issue that could be easily resolved by Google. 

https://code.google.com/p/android/issues/detail?id=82

To encourage Google to finally add support for this long requested feature, please go to the above URL and star it.

To emphasise the feasibility of Google addressing this problem, yet being unwilling to do so, the lack of ad-hoc support is primarily the result of the active and purposeful removal of ad-hoc support from wpa_supplicant, and more recently, from the Wi-Fi drivers on the handsets. 

Ad-hoc Wi-Fi has been enabled on some handsets by simply replacing the crippled wpa_supplicant with a fully functional version.

Patches have been submitted to Google and also to the Android Open Source Project (AOSP) in recent times.  

While Google has refused to integrate them, I believe that the changes are making their way into the AOSP itself.

No convincing reasons have been given by Google as to why they continue to refuse to stop disabling ad-hoc Wi-Fi in Android.

Some claimed reasons include:

1. "Ad-hoc Wi-Fi lacks security". This is also true of "normal" Wi-Fi if WPA or similar is not used. Also, it is possible to use WPA/WPA2 on ad-hoc Wi-Fi, so this claim is defeated twice.

2. "Wi-Fi Direct does the same thing and is better". Wi-Fi direct only allows very small groups of devices to form a P2P "network", which really consists of one phone being a Wi-Fi hotspot and the others being clients.  It does not allow true ad-hoc networking, such as allowing handsets to come into range of one another and begin communicating without requiring user interaction. Similarly only ad-hoc Wi-Fi can allow large numbers of handsets to communicate.  In short, Wi-Fi Direct is not the same thing as ad-hoc Wi-Fi, and cannot satisfy the same use-cases.

3. "We will add it soon".  This has been claimed a few times in the FIVE YEARS the bug has been left open.  The reality indicates a lack of actual desire to address the bug.  Some might say that Google is caving into unjustified carrier concerns that if mobile phones can communicate with one another that their business model will be impacted.  There is no reason to suggest that there is any validity to carriers concerns (Wi-Fi has an urban range of <100m, compared with 3km - 30km for cellular signals, so any fear is without rational basis).

Perhaps a Google/Android representative on this list could raise their hand, and indicate that they look into the matter for us again, and report on the current plans within an agreed time frame, e.g., 14 days.

You can go through the archives of this Google Group to find several previous similar enquiries, regrettably without definitive responses by Google/Android engineers.

In the meantime, I believe that CyanogenMod on some handsets includes their framework for ad-hoc.

Also SPAN, OTI/Commotion and our own Serval Mesh software is able to obtain ad-hoc mode on certain models of handset.

Let me know if you would like more information on these projects, what model of handset you have, and perhaps what you would like to achieve using ad-hoc Wi-Fi on Android.

Paul.

On Friday, April 19, 2013 12:10:18 AM UTC+9:30, elis...@argence.eu wrote:

Does android 4.1 allows peer-to-peer connections in ad-hoc WIFI mode ?

[elis...@argence.eu]

I am a mathematics teacher in Carcassonne (France) and I try to connect my students to my Moodle Server by local network wirless-mode open ad-hoc (no WPA/WPA2). Some students have netbooks.  I'd like they use tablets instead. I'm gonna patch android if possible, it seems depend on whitch tablet is used. My KINDLE detects ad-hoc but does not support it. I try to find a tablet that do support it.

Thanks for your very helpful answer.

[Paul Gardner-Stephen]

Hello,

For your use case it is probably easier to get the device running your Moodle instance to run as a Wi-Fi hotspot instead of in ad-hoc mode.  That way your students can connect as normal Wi-Fi clients.

If your desire is to create a distributed learning management system, this is something that we would be very interested to explore with you.

Paul.