Cracking of wireless networks

Cracking of wireless networks is the defeating of security devices in Wireless local-area networks. Wireless local-area networks(WLANs) – also called Wi-Fi networks are inherently vulnerable to security lapses that wired networks are exempt from.

Cracking is a kind of information network attack that is akin to a direct intrusion. There are two basic types of vulnerabilities associated with WLANs: those caused by poor configuration and those caused by weak encryption.

802.11 networks use data frames, management frames, and control frames. Data frames convey the real data, and are similar to those of Ethernet. Management frames maintain both network configuration and connectivity. Control frames manage access to the ether and prevent access points and clients from interfering with each other in the ether. Some information on management frames will be helpful to better understand what programs for reconnaissance do.

Wardriving is a common method of wireless network reconnaissance. A well-equipped wardriver uses a laptop computer with a wireless card, an antenna mounted on the car, a power inverter, a connected GPS receiver, and can connect to the internet wirelessly. The purpose of wardriving is to locate a wireless network and to collect information about its configuration and associated clients.

The laptop computer and the wireless card must support a mode called monitor or rfmon.

Netstumbler is a network discovery program for Windows. It is free. Netstumbler has become one of the most popular programs for wardriving and wireless reconnaissance, although it has a disadvantage. It can be detected easily by most wireless intrusion detection systems, because it actively probes a network to collect information. Netstumbler has integrated support for a GPS unit. With this support, Netstumbler displays GPS coordinate information next to the information about each discovered network, which can be useful for finding specific networks again after having sorted out collected data.

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Wikipedia