wirelesstutorial

T he tools you use are only as good as the hardware they are running on, but the best wireless card and chipset in the world is useless if the driver controlling it has no idea how to make it do what you want. This section introduces you to the currently available drivers, the chipsets that they control, and the cards that have the chipsets in them. There is a strong emphasis on Linux drivers, because this is where most of the development is currently happening. Before getting into the nitty gritty details of chipsets and drivers, some information on why drivers and chipsets are so important in wireless hacking is needed.

Wi-Fi is a subset of the 802.11 standard that is managed by the Wi-Fi Alliance. Because the 802.11 standard is so large, and the process required to update the standard can take awhile (it's run by a committee), nearly all of the major wireless equipment manufacturers decided they needed a smaller, more nimble group dedicated to maintaining interoperability among vendors. This resulted in the creation of the Wi-Fi Alliance. The Wi-Fi Alliance assures that all products with a Wi-Fi-certified logo work together. This way if any ambiguity in the 802.11 standard crops up, the Wi-Fi Alliance defines the "right thing" to do. It also allows vendors to implement important subsets of draft standards (standards that have not yet been ratified). The most well-known example of this is Wi-Fi Protected Access (WPA) or "draft" 802.11n equipment.

The 802.11 standard defines a link layer wireless protocol and is managed by the Institute of Electrical and Electronics Engineers (IEEE). Many people think of Wi-Fi when they hear 802.11, but they are not quite the same thing. In recent years, Wi-Fi and 802.11 have exploded in popularity, and every new laptop comes with a builtin Wi-Fi adapter. This popularity has led to a surge of research into the security of the 802.11 standard. The history about the first 802.11 standard was approved in 1997 and allowed transmission speeds that topped out at 2 Mbps. This version of the standard allowed two different methods for encoding information at a physical level, Frequency Hopping Spread Spectrum (FHSS) and Direct Sequence Spread Spectrum (DSSS). These two different encoding schemes are incompatible, however, and the choice led to a lot of confusion in the marketplace.