Are Intrusion Prevention System only for big companies?

Intrusion prevention systems (IPS), also known as intrusion detection and prevention systems (IDPS), are network security appliances that monitor network and/or system activities for malicious activity. The main functions of intrusion prevention systems are to identify malicious activity, log information about said activity, attempt to block/stop activity, and report activity. Intrusion prevention systems are considered extensions of intrusion detection systems because they both monitor network traffic and/or system activities for malicious activity.

The main differences are, unlike intrusion detection systems, intrusion prevention systems are placed in-line and are able to actively prevent/block intrusions that are detected. 23 More specifically, IPS can take such actions as sending an alarm, dropping the malicious packets, resetting the connection and/or blocking the traffic from the offending IP address. 4 An IPS can also correct Cyclic Redundancy Check (CRC) errors, unfragment packet streams, prevent TCP sequencing issues, and clean up unwanted transport and network layer options.

Network-based intrusion prevention system (NIPS): monitors the entire network for suspicious traffic by analyzing protocol activity. Wireless intrusion prevention systems (WIPS): monitor a wireless network for suspicious traffic by analyzing wireless networking protocols. Network behavior analysis (NBA): examines network traffic to identify threats that generate unusual traffic flows, such as distributed denial of service (DDoS) attacks, certain forms of malware and policy violations.

Host-based intrusion prevention system (HIPS): an installed software package which monitors a single host for suspicious activity by analyzing events occurring within that host. The majority of intrusion prevention systems utilize one of three detection methods: signature-based, statistical anomaly-based, and stateful protocol analysis. Signature-Based Detection: This method of detection utilizes signatures, which are attack patterns that are preconfigured and predetermined.

A signature-based intrusion prevention system monitors the network traffic for matches to these signatures. Once a match is found the intrusion prevention system takes the appropriate action. Signatures can be exploit-based or vulnerability-based.

Exploit-based signatures analyze patterns appearing in exploits being protected against, while vulnerability-based signatures analyze vulnerabilities in a program, its execution, and conditions needed to exploit said vulnerability.