EC-Council Certified Ethical Hacker (CEH) v13 (312-50v13) Practice Exam

IDS stands for Intrusion Detection System and is a security mechanism that monitors network traffic or host activity for signs of unauthorized access or policy violations. It can be network-based, analyzing packets and traffic patterns, or host-based, watching logs and system calls. Detection relies on signatures of known attacks or anomaly-based models that flag behavior outside the normal baseline. When something suspicious is detected, the IDS raises alerts and forwards information to security personnel or a SIEM for correlation; it primarily detects and reports rather than actively blocking traffic. This distinguishes it from an Intrusion Prevention System, which can block threats in-line. The other terms—Integrated Defense System, Internet Data Security, and Intrusion Delimiter System—are not standard security terms for this function and do not describe how this technology operates.