Intruder detection system (IDS) evasion

Intrusion detection system (IDS) is a technology, be it a software or hardware, that automatically scans events occurring in computer or network for signs of security problems. IDS evasion is the act of executing any illegal activity towards the target host without being detected by the IDS. Such activities can be invading, hacking, transmitting malicious data or simply inflicting damage. The methods used in the evasion may be insertion, evasion and ambiguities. These attacks can be conducted in any layer in the OSI model. Thus, in this study, major and well known evasion techniques are exposed and discussed. Countermeasures are also mentioned and listed down in order to mitigate the threat of IDS evasion