What is an Intrusion Detection System (IDS)?

An intrusion detection system is a system that analyses network traffic for suspicious activity and sends notifications if it detects unwanted behaviours.

While anomaly detection and reporting are an IDS’s primary functions, specific intrusion detection systems can execute action if they discover malicious behaviour or abnormal traffic, such as restricting traffic from questionable Internet Protocol (IP) addresses.

An intrusion detection system (IDS) differs from an intrusion prevention system (IPS), which, like an IDS, analyses network packets for potentially hostile network traffic but focuses on preventing attacks once they have been discovered rather than detecting and recording them.

How Does an Intrusion Detection System Work? 

Intrusion detection systems identify anomalies to prevent and obstruct hackers before they cause significant harm to a network. IDSes can be network or host-based. A host-based intrusion detection system is placed on a client computer, whereas a network-based intrusion detection system is present on the network.

Intrusion detection systems scan for signatures of known attacks or changes from regular behaviour. These deviations or abnormalities are passed up the stack and investigated at the protocol and application layers. They can detect Christmas tree scans and Domain Name System (DNS) poisonings accurately.

Moreover, an intrusion detection system (IDS) can be established as either a software program operating on customer hardware or a network security appliance. Cloud-based intrusion detection technologies are also available to protect information and systems in cloud-based environments.

Different Types of Intrusion Detection Systems 

IDSes are present in numerous functions and identify suspicious activities using different methodologies, such as the following:

1. A network intrusion detection system (NIDS) records inbound and outbound traffic across all network devices.
2. A host intrusion detection system (HIDS) protects all networked computers and gadgets with direct internet and internal network access. A HIDS has an advantage over a NIDS in that it may detect unusual network packets from within the business and malicious traffic that a NIDS failed to detect. A HIDS may also detect harmful communication from the host, such as when the host is infected with malware and tries to propagate to other systems.
3. Signature-based intrusion detection systems (SIDS) scan network packets and compare them to a database of known dangerous threats, similar to antivirus software.
4. An anomaly-based intrusion detection system (AIDS) compares network data against a baseline to determine normal network parameters such as bandwidth, protocols, ports, and devices. This type frequently employs machine learning to set a baseline and subsequent security policy. It then notifies IT personnel of questionable activities and policy infractions. By detecting threats using a comprehensive model rather than specific signatures and traits, the anomaly-based detection method overcomes the limitations of signature-based methods, particularly in identifying new threats.

Historically, intrusion detection systems were either passive or aggressive. A passive IDS that detects malicious activity creates alerts or log entries but does not tolerate action. An active IDS, an intrusion detection and prevention system (IDPS), would develop warnings and log entries. Still, it might also be programmed to perform actions such as blocking IP addresses or denying access to restricted services.

Capabilities of Intrusion Detection Systems 

Intrusion detection systems analyse network traffic to identify attacks executed by threat actors or unknown entities. IDSes accomplish this by offering security experts some — or all — of the following capabilities:

1. Monitoring routers, firewalls, critical management servers, and files for cyberattack detection, prevention, and recovery.
2. Assist administrators in organising and comprehending OS audit trails and logs, which can be challenging to manage and analyse.
3. Providing a user-friendly interface to let non-expert workers manage system security.
4. Includes a database of attack signatures to match system information.
5. Identifies and reports data file changes detected by the IDS.
6. Notifying of security breaches and creating alarms.
7. Reacting to intruders by blocking them or the server.

Advantages of Intrusion Detection Systems 

Intrusion detection systems provide enterprises with various advantages, beginning with the capacity to detect security issues. An IDS can help assess the number and types of assaults. Organisations can use this data to improve security systems or adopt more effective controls. An intrusion detection system can also assist businesses in identifying faults or issues with their network device setups. These measures can then be used to evaluate potential risks.

Intrusion detection systems can also help businesses achieve regulatory compliance. An IDS gives enterprises more visibility throughout their networks, making it easier to comply with security laws. In addition, firms can utilise their IDS logs as proof to demonstrate that they are satisfying specific compliance standards.

Intrusion detection systems can also aid in security response. IDS sensors can detect network hosts and devices but can also scan data within network packets and identify the operating systems services they utilise. Using an IDS to get this information can be more efficient than doing manual censuses of connected systems.

How can iZOOlogic help my Company or Organisation?

Find out how iZOOlogic can provide a proper intrusion detection system through our Incident Response solutions under our Threat Management Services.

To find out more about how iZOOlogic can help protect your company’s cyber security, schedule a demo.