An intrusion detection system (IDS) is a device or software application that monitors network or system activities for malicious activities or policy violations and produces reports to a management station.

2. An intrusion detection system (IDS) is
a device or software application that
monitors network or system activities
for malicious activities or policy
violations and produces reports to a
management station.
Intrusion Detection System

3. Intrusion detection systems are an additional layer of security to
protect network
Roles of a intrusion
detection system:
• Gathers and analyses information from a computer or Network
• It works as a packet sniffer
• Capture and analyzed the captured packets
• Evaluate a suspected intrusion and signals an alarm.

5. The working of an intrusion detection
system
The main purpose of Intrusion detection system are that they do not only
prevent intrusion but also alter the administrator immediately when the attack
is still going on.
IDS have sensors detect signature
If the signature matches the packet is dropped, and
the alarm notifies the admin.

6. Ways to detect intrusion:
Signature Detection
Anomaly detection
Protocol anomaly detection