Vlogcanic

A brief abstract from the current situation for users who are seriously considering to get Linux working under wireless and WiFi LANs.

While there’s no doubt that Linux is the right operating system for unleashing the full potential of a good WiFi card, it is also true that the range of workable cards under Linux is not yet as wide as in Windows and that, depending on your chipset, they can work well, not so well or not work at all.

The point in this post is to explain to the not-so-experienced users who think they’re ready to emmigrate the essentials of the current love-hate relationship between Linux and Wi-Fi so that their transition is as painless as possible.

Drivers vs. Modules.

Whatever advantages Linux offers over Windows (and there are many), hardware support is not among them. I hate to say it but that’s just the way it still is.

In Windows, as you probably know already, hardware is made to work with the OS with a bunch of little programs called drivers. Linux, on the other hand, has modules or kernel modules to accomplish the task. The thing about WiFi cards is that there are not as much Linux modules available as there are drivers in Windows, and this is why: consumer and personal use hardware manufacturers want to have their products available to the largest possible market in the cheapest way possible. In other words: they need their stuff to work properly under Windows while Linux compatibility is not so big a priority. As a result most of them don’t see the point in developing Linux modules.

All is not lost, however. There are a few companies which do support Linux and there are ongoing efforts by free and open source development communities aiming to provide Linux with the modules needed to use WiFi cards. Each new kernel version can recognize and work with more hardware than ever before.

And yet the fact remains that not all WiFi cards can be rendered useful under Linux, and those that can have varying degrees of functionality It all boils down to the little set of things that are responsible for the WiFi’s card magic: the chipset.

Chipsets.

The chipset is the key to comptibility. Not the brand, not even the model number–as those are both cosmetic elements introduced by the packager. It is the chipset that drives the WiFi card forward and there are only a handful of chipset manufacturers in the world –not unlike the CPU world in which, if you are in the personal desktop market you can only go with Intel or AMD regardless of the computer brand you choose.

The first thing any new user must realize is that the chipset is the relevant piece of equipment as many different brands use the same chipsets but some brands offer different chipsets in the same card model.

As I stated before, some chipset manufacturers (like Ralink) do support Linux and usually make modules available along with Windows drivers. Some of those modules are already available to you in your Linux kernel, some others require that you install them. You’ll know if the first case applies to you if your Linux system recognized your WiFi card and started working with it as soon as you plugged it in. If that wasn’t you, keep reading.

If your WiFi card didn’t start up upon pluggin it, there are other choices. Maybe you need to find out your chipset’s name and model –more on that below– and go to the manufacturer’s web page to search for Linux drivers. If and when they are available they usually need to be compiled and installed manually, have a careful look to the README file and follow the instructions.

Alternatively there are some very active development communities engaged in getting a particular chipset to work under Linux. MadWiFi, for instance, is focused on Atheros chipsets; Prism54 on prism chipsets. Once you know what chipset you own, you can select the appropiate communitie to fit your needs and visit their webpage for downloads and instructions.

If you’ve read this far, you are probably asking yourself these questions: How do I know if my WiFi card works with Linux? How can I choose the right card to work with Linux? or How can I find out what chipset is in my WiFi card? Keep reading.

How do I find out which WiFi chipset is in my WiFi card?

There’s a whole bunch of sites devoted to answer that very question. My favorite is Linux Wireless LAN Support, which has an extensive and updated list of WiFi cards sorted by brand, model, chipset and the kernel module’s state of the art for that chipset along with links to the download and development sites.

Also it will always be worth your while to go to your distro’s forums and do a bit of research about other users experiences with your card and your distro. You’ll find tips, how-to’s, and other important information.

There’s a chance you’ll find there is no Linux module for your card. There’s also a chance that you’ll find one that won’t work. It’s not a reason to give up, keep reading.

NDIS Wrapper.

NDIWrapper is yet another remarkable achievement by an open source/free software driven development community. It’s a Linux program designed  to use a Windows driver in a Linux OS. So if there’s no module for your card but you have a driver that works well under Windows, you can always give it a go with NDISWrapper. It won’t allways work but it’s worth the shot.

In order to do that, you must first download and install NDISWrapper and it won’t hurt to visit the NDISWrapper website and find out what other users say about your card and NDISWrapper.

There is a chance too that you won’t be able to make your card work even with NDISWrapper, depending on your chipset. If that happens then you might just be out of luck, and there’s nothing to do but wait or get a new card.

WiFi and special applications.

Last but not least, if what you want is a WiFi card to use in security applications, then you couldn’t made a better choice: Linux is the way to go. But the range of usable WiFi cards shrinks even more.

WiFi and wireless LAN security applications need your card’s driver to be able to put it in monitor mode, a feat which only a few drivers and chipsets are up to. Atheros and Prism are among the expert’s chipsets of choice for this kind of thing.

While some drivers can be patched for this purpose, the optimal thing to do is to choose the right chipset for the right task so if you want to go WiFi hacking you better get yourself a proper chipset for the job.

Conclusion.

Making a WiFi card work in Linux can be hell if you don’t choose the hardware at least a bit carefully. Newer and rarer chipsets are harder to install. So before you choose a wireless card, find out its chipset, check the module avilability, perfomance under NDISWrapper and see what other people is writing about it on your distro’s forums.

However long a time you spend getting all the information you need, it will be much shorter than the long frustrating hours needed just to find out, the hard way, that you have an unsupported, unworkable chipset.