What is authentication/change-detection software?
Change-detection software determines whether the program, file, or system has changed as compared against a previously established database. It examines system and/or program files and configuration, stores the information, and compares it against the actual configuration at a later time. Most of these programs perform a checksum or cyclic redundancy check (CRC) that will detect changes to a file even if the length is unchanged. Some programs will even use sophisticated encryption techniques to generate an authentication signature that is, if not absolutely immune to malicious attack, prohibitively expensive, in processing terms, from the point of view of a virus. If a sufficiently broad overview of the system is taken, this will provide 100 percent effective detection of a viral infection, but it also may raise a number of false alarms. Change-detection software is also often referred to as integrity-checking software. It does check the integrity of the program in terms of alterations
