SIEM is a set of tools that combines security event management (SEM) with security information management (SIM) to detect and respond to threats that breach a network. The system aggregates data from all of the devices on a network to determine when and where a breach is happening. This way, the IT team can respond more quickly and contain the breach before it does any more damage.

Enterprise companies with a large number of devices on their networks purchase SIEM tools, allowing them to pull log data from hardware, operating systems, applications, and security tools to monitor the network in real time. These companies also dedicate IT personnel to maintaining the system, monitoring for threats, and responding to those threats. Some common SIEM examples you might have heard of include ArcSight ESM (Enterprise Security Management), AT&T Cybersecurity (formerly known as AlienVault), Fortinet, IBM QRadar, McAfee SIEM, and Splunk.

The software’s scope and resource requirements mean that it’s not a practical option for most small businesses. Additionally, the software can cost tens of thousands of dollars per year, making it cost prohibitive for many small businesses. Thus, SIEM is usually a better solution for enterprise security.

Security information and event management (SIEM) is a configurable system of record that collects, aggregates and analyzes security event data from on-premises and cloud environments. SIEM processes security event data for the purposes of threat detection, investigation and response. It natively supports data normalization and offers user-configurable detection content and reporting to orchestrate threat mitigation and satisfy compliance requirements. These solutions are delivered via a SaaS platform or client-hosted on-premises or private cloud.

The security information and event management (SIEM) system must assist with:

1. Aggregating and normalizing data from various IT and operational technology (OT) environments.

2. Designing and executing near real-time monitoring and alerting content.

3. Enriching and investigating security events of interest.

4. Supporting manual and automated response actions.

5. Maintaining and reporting on current and historical event data.