What is SIEM?

Security information and event management (SIEM) is a platform that aggregates event log data and outputs alerts on incidents of interest. Learn more about how SIEM can help Managed Detection and Response (MDR).

SIEM definition

Security information and event management (SIEM) is a system that pulls event log data from various security tools to help security teams and businesses achieve holistic visibility over threats in their network and attack surfaces. With SIEM tools, cyber security analysts detect, investigate, and address advanced cyber threats which allows security teams to prioritize, interpret, and analyze aggregate data on cybersecurity incidents in a central place. Organizations are uniquely positioned with SIEM to not only handle existing cyberattacks but better understand event data to prevent future breaches.

SIEM security delivers real-time protection through network security monitoring, log information collection, and event data analysis. This system offers broader threat detection coverage into the organization’s vast cyber environment. Security information and event management tools are used to assist IT, SOC analysts (Security Operations Center)MDR providers (Managed Detection and Response), and SecOps teams who conduct threat investigation and track malicious behavior.

What is next-gen SIEM?

SIEM has made advancements over the years to include user and entity behavior analytics (UEBA). Advantages of next-gen SIEM consist of AI-based technology to profile user activity and run behavior analysis. So, how does next generation SIEM differ from Security Orchestration, Automation, and Response (SOAR) tools? Read our article: What is SOAR?

How does SIEM work?

SIEM solutions consolidate the collection of event data and log information from various data points. IT teams and security staff use SIEM to gather threat intelligence from next-gen antivirus (NGAV) events, endpoint detection and response, firewalls, user applications, cloud environments, and network flow data all in a centralized place. Through this single pane of collected data, SIEM allows incident response analysts to monitor real-time event log management, examine digital forensics, and report attacker behavior. It works with tactics, techniques, and procedures (TTP), a method used in the MITRE ATT&CK framework which helps security personnel depict insights on specific threat actor activity. Event log intelligence assists security analysts in identifying indicators of compromise (IOCs) of data breaches and malware intrusions. Log management, event analysis, and alert monitoring are key areas that comprise SIEM alerts.

Log management capabilities

What is log management? The log management process helps businesses and IT security teams continuously handle robust volumes of log data. Log management includes data aggregation, normalization, storage, documentation, and disposal.

Data aggregation describes the gathering and consolidation of event log data into one location. This raw data is retrieved from multiple sources, applications, and databases.  

In simple terms, event normalization involves the comparison, correlation, and analysis of dissimilar data. When event data is collected from various sources (firewalls, servers, and databases as earlier mentioned), many challenges arise from inconsistent log formatting. Event data normalization is a process that sorts raw event input into variables which security administrators used to prepare readable, structured format and map the fields most relevant with important data.

Event correlation and analysis

Event analysis involves identifying indicators of security breaches, vulnerabilities, and threat anomalies. SIEM helps security professionals contextualize event information in a single place and prioritize log data into categories. This categorized data let’s security personnel map types of events occurring in real-time and historically across the entire network.

Event monitoring advanced alerts

Offering continuous monitoring, SIEM solutions play a huge role in organizing and prioritizing event information from tools in your company’s technology stack. A SIEM software pairs events against predetermined rules to assess the severity and threat level to create a SIEM alert. Rule-based detection defines a base level for suspicious activity and alleviate your security team’s time expenditure toward investigating false positives.

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Why SIEM solution is important for your organization?

SIEM tools are used by IT security departments for several reasons. Although it is commonly thought of as a response tool, SIEM offers preventative protection against threats by catching unusual behavior, such as multiple failed logins and system failures before vulnerabilities are exploited.

Regulatory compliance

SIEM can help organizations comply with GDPR, HIPPA, and PCI DSS. Compliance regulations are perpetually changing, and businesses of all sizes need to keep their security strategy up to date. SIEM can be used as a tool to create compliance reports in real-time. Security management utilize SIEM to detect and address compliance violations sooner.

Behavior based threat detection

With SIEM software, businesses work toward achieving comprehensive visibility over their cyber landscape through dashboarding log files and analyzing events. SIEM leveraging UEBA work in tandem to recognize dubious network activity and perform behavior analysis.

Event data retention

SIEM technology can store historical data valuable for tracking, analyzing, and aggregating data for compliance purposes. By saving a history of data, analysts can trace event information during digital forensic investigation.


SIEM is a fundamental tool used by SOCs (security operations center) to understand behavioral analytics of threat anomalies. SOC analysts rely on SIEM to determine the severity of cyber incidents and contain intrusions before they reach critical company assets. SIEM alleviates the volume of alerts for SOC security teams who readily address the high priority attacks.

EDR vs SIEM tools

Endpoint detection and response (EDR) works in tandem with SIEM to deliver holistic visibility over devices, servers, and systems in your organization. SIEM cybersecurity is a rule-based tool that offers strength in detection capabilities, however EDR is widely known as a strong tool for prevention of cyberattacks on endpoints.

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What is SIEM and how it works?

SIEM stands for security information and event management and is a system which uses a suite of detection and response tools to gather, compress, and analyze event log data from your business’ security infrastructure.

Is SIEM a firewall?

Security information and event management (SIEM) is not a firewall, but aggregates log file data from events sourced from your organization’s security stack which includes firewalls, endpoint detection and response tools (EDR), antivirus software, and other systems.

What is cloud-based SIEM?

Cloud-based SIEM manages threat logs across on-premise and cloud environments on a single pane. With a centralized dashboard, cloud SIEM gives businesses the flexibility to store, consolidate, and analyze security data to improve overall security posture.