Network Access Layer (2): Wireless Mobile Lan Technologies

The days when access to the Internet was only possible from the home or office via a wired computer are long gone. For several years now, mobility has been the primary focus, whether it be using a laptop to access the company network while on the go or reading emails on a cell phone. This unlimited availability has been enabled by mobile communication technologies that make the normal LAN accessible anywhere. And all this without having to worry about bothersome cabling management. The wireless LAN (or WLAN) provides us today with a performance comparable to wired LAN technology But this new found freedom is not without its darker side. With wired network technologies, unauthorized intruders and attackers had been forced to first gain physical access to the foreign network before intrusion could be carried out. The WLAN of today does away with fixed structural borders and can be received barrier-free by everyone within its transmission radius. This has made security technologies and encryption techniques inseparable with wireless network technologies. The present chapter introduces the foundations of the WLAN technology and will also look at the necessary security standards and encryption methods that allow the secure implementation of wireless technology In addition to WLANs, close range networks, so-called Personal Area Networks (PANs), are gaining increasing importance. These have the capability of linking devices autonomously and wirelessly within the radius of only a few meters. Prominent examples of PAN technologies - Bluetooth and ZigBee - will be examined in detail.