File Type Detection Technology （文件类型检测技术）.pdf

File Type Detection Technology Douglas J. Hickok Computer Science and Software Engineering Department University of Wisconsin – Platteville Platteville, WI 53818 hickokd @ Daine Richard Lesniak Computer Science and Software Engineering Department University of Wisconsin – Platteville Platteville, WI 53818 lesniakd @ Michael C. Rowe, Ph.D. Computer Science and Software Engineering Department University of Wisconsin – Platteville Platteville, WI 53818 rowemi @ Abstract File type identification is a difficult but increasingly important task. There are no global standards for file types and there are catalogues of several thousand known file types. Filters, such as email SPAM, virus blockers, adware/spyware, and steganalysis detectors are generally file type specific and may need accurate file type knowledge to work effectively. Corporations and government agencies block specific file types in an attempt to keep sensitive data from leaving or worms and viruses from entering their networks. Another important use of file type is as a means of limiting “recreational” file use that can absorb significant quantities of network bandwidth and storage. Some of the more commonly filtered file types for the above considerations include: “.vb”, “.vbs”, “.exe”, “.mp3”, “.wav”, “.mpeg”, “.wmv”, and “.avi”. Introduction With privacy, security, and wise use of computational resources becoming increasingly important to organizations, the technologies that address these concerns are increasin