What are the two main types of Intrusion Detection Systems (IDS)?

The two main types of Intrusion Detection Systems (IDS) are Network-based IDS (NIDS) and Host-based IDS (HIDS). NIDS monitors and analyzes traffic on a network as a whole, looking for signs of suspicious activity by examining packets that travel across a network segment. This type of system is positioned at strategic points within the network to oversee traffic entering and leaving.

On the other hand, HIDS is installed on individual hosts or devices, such as servers and workstations, and is responsible for monitoring system-level events and activities. This includes tracking processes, file accesses, and changes to configuration files. HIDS is especially useful for detecting unauthorized access or modifications made from within an organization's network.

These two types of IDS serve complementary roles: NIDS provides a broader view of network-wide activity, while HIDS offers a focused perspective on specific devices. Together, they enhance an organization's overall security posture by providing layers of detection across different attack vectors.