An intrusion detection system (IDS) is an application that monitors network traffic and searches for known threats and suspicious or malicious activity. The IDS sends alerts to IT and security teams when it detects any security risks and threats.
Most IDS solutions simply monitor and report suspicious activity and traffic when they detect an anomaly. However, some can go a step further by taking action when it detects anomalous activity, such as blocking malicious or suspicious traffic.
IDS tools typically are software applications that run on organizations’ hardware or as a network security solution. There are also cloud-based IDS solutions that protect organizations’ data, resources, and systems in their cloud deployments and environments.
What Is An Intrusion In Cybersecurity?
An intrusion in cybersecurity is typically an attacker gaining unauthorized access to a device, network, or system. Cyber criminals use increasingly sophisticated techniques and tactics to infiltrate organizations without being discovered. This includes common techniques like:
- Address Spoofing: The source of an attack is hidden using spoofed, misconfigured, and poorly secured proxy servers, which makes it difficult for organizations to discover attackers.
- Fragmentation: Fragmented packets enable attackers to bypass organizations’ detection systems.
- Pattern Evasion: Hackers adjust their attack architectures to avoid the patterns that IDS solutions use to spot a threat.
- Coordinated Attack: A network scan threat allocates numerous hosts or ports to different attackers, making it difficult for the IDS to work out what is happening.
Types Of Intrusion Detection Systems (IDS)
IDS solutions come in a range of different types and varying capabilities. Common types of intrusion detection systems (IDS) include:
- Network Intrusion Detection System (NIDS): A NIDS solution is deployed at strategic points within an organization’s network to monitor incoming and outgoing traffic. This IDS approach monitors and detects malicious and suspicious traffic coming to and going from all devices connected to the network.
- Host Intrusion Detection System (HIDS): A HIDS system is installed on individual devices connected to the internet and an organization’s internal network. This solution can detect packets from within the business and additional malicious traffic that a NIDS solution cannot. It can also discover threats originating from the host itself.
- Signature-Based Intrusion Detection System (SIDS): A SIDS solution monitors all packets on an organization’s network and compares them with attack signatures in a database of known threats.
- Anomaly-Based Intrusion Detection System (AIDS): This solution monitors traffic on a network and compares it with a predefined baseline considered "normal." It detects anomalous activity across the network, using machine learning to adapt the baseline and improve threat detection.
- Perimeter Intrusion Detection System (PIDS): A PIDS solution is placed on the perimeter of an organization’s network to detect intrusion attempts at critical infrastructure boundaries.
- Virtual Machine-Based Intrusion Detection System (VMIDS): A VMIDS solution monitors virtual machines, enabling organizations to track traffic and security events across all connected devices.
- Stack-Based Intrusion Detection System (SBIDS): SBIDS is integrated into an organization’s Transmission Control Protocol/Internet Protocol (TCP/IP) stack, which helps monitor packets as they move through the network and prevent malicious packets from being processed by the operating system or applications.
How Does An Intrusion Detection System Work? What Are Its Uses?
IDS solutions excel in monitoring network traffic and detecting anomalous activity. They are placed at strategic locations across a network or on devices to analyze network traffic and recognize signs of potential attacks.
An IDS works by looking for the signature of known attack types or detecting activity that deviates from a prescribed normal behavior. When it detects such anomalies, it alerts administrators so they can examine the situation further. This helps organizations detect the early signs of an attack.
Some of the key functions of IDS include:
- Monitoring the performance of key firewalls, files, routers, and servers to detect, prevent, and recover from cyberattacks.
- Helping administrators organize and manage audit trails and logs of operating systems, which can often be difficult to track manually.
- Providing an easy-to-use interface that allows staff, even those not experts in security, to assist with managing systems.
- Offering a database of attack signatures that can match and detect known threats.
- Generating reports of anomalous or malicious activity to alert administrators and security teams of potential breaches.
- In some cases, actively blocking malicious actors to prevent further intrusion or damage.
Why Are Intrusion Detection Systems (IDS) Important?
Intrusion Detection Systems provide an additional layer of security, making them a crucial part of an effective cybersecurity strategy. They work alongside other security tools to detect threats that might bypass primary defenses, helping alert administrators of malicious activity and enabling faster response times.
Benefits of Intrusion Detection Systems:
- Understanding Risk: IDS tools help businesses assess the number and types of attacks they are facing, giving insight into the sophistication of risks they may face.
- Shaping Security Strategy: The insights from an IDS can help shape and evolve a comprehensive cybersecurity strategy to combat current and future threats.
- Regulatory Compliance: IDS tools provide visibility into network activity, helping organizations meet data security regulations and document compliance with ease.
- Faster Response Times: IDS solutions provide immediate alerts, enabling organizations to identify and neutralize threats much quicker than manual monitoring.
