The term sniffing, as it relates to the Internet, is the process of intercepting data traffic as it travels from one point to another. Sniffers, also called packet sniffers or network sniffers, are the tools that capture and save the data for later analysis. Wireless sniffers can capture this data over wireless Local Area Network (LAN) channels. Although wireless sniffers have many legitimate uses, they are also common hacking devices that malicious users can leverage for ulterior motives.
Streams of data that flow over a wireless LAN travel in discrete units called data packets. Wireless sniffers are software programs that can listen in on a LAN's wireless channels and capture those packets. The sniffing program runs on a computing device that has an 802.11 wireless LAN adapter. The program sends commands to the adapter, which then captures and sends the data packets back to the sniffer. Users of the wireless sniffer can then access and read the transmitted data.
Network administrators and IT managers can use wireless sniffers to monitor and troubleshoot wireless LANs. They are useful tools for analyzing network problems, monitoring network usage, detecting network misuse or external intrusions, and filtering out inappropriate content. Administrators can use sniffing tools to monitor the effectiveness of spam filters, network firewalls, and access control and intrusion prevention systems.
Hackers can use wireless sniffers for malevolent purposes. People with a bit of technological savvy can use these devices to not only wreak mischief on company networks and personal wireless devices, but for personal profit. Hackers can capture confidential company information, as well as personal information, passwords, and Media Access Control (MAC) addresses. With that information, they can access accounts, send spam emails from a spoofed email address, or direct web users to malicious websites, among other uses.
Users and IT managers need to make sure they use adequate protection to prevent wireless sniffers from being used inappropriately. Security protocols such as Secure Sockets Layer (SSL), Wi-Fi Protected Access, (WPA), Wired Equivalent Privacy (WEP) can help protect a network. Use of encryption and a solid foundation in regular security practices can help thwart malicious uses of wireless sniffers.
Wireless sniffers are readily available for those who want to use the technology for network monitoring, troubleshooting, and protection. Those people who want the programs for malicious purposes, however, can access the technology just as easily. Therefore, it's important that IT personnel and home users be vigilant and use proper security protection.