Intrusion detection system (IDS)

An intrusion detection system (IDS) is a device or software application that monitors network and/or system activities for malicious activities or policy violations and produces reports to a Management Station. Intrusion prevention is the process of performing intrusion detection and attempting to stop detected possible incidents. Intrusion detection and prevention systems (IDPS) are primarily focused on identifying possible incidents, logging information about them, attempting to stop them, and reporting them to security administrators. In addition, organizations use IDPSs for other purposes, such as identifying problems with security policies, documenting existing threats, and deterring individuals from violating security policies.  IDPSs have become a necessary addition to the security infrastructure of nearly every organization

IDPSs typically record information related to observed events, notify security administrators of important observed events, and produce reports.  Many IDPSs can also respond to a detected threat by attempting to prevent it from succeeding. They use several response techniques, which involve the IDPS stopping the attack itself, changing the security environment (e.g., reconfiguring a firewall), or changing the attack’s content.

Intrusion detection is the ability to identify, track, and stop unauthorized or malicious attacks before they can penetrate and damage your network. Intrusion detection capability is only one part of a complete data security model and complements existing components, such as firewalls, encryption mechanisms, strong authentication systems, etc.

Almost all intrusion detection technologies fall into two basic types of intrusion detection - network-based and host-based.

• A network-based intrusion detection system (IDS) monitors traffic flowing through a network, looking for patterns that indicate unauthorized or malicious activity is taking place.
  
• Host-based and network-based intrusion detection systems can prove invaluable in fortifying your defensive posture.