What is SIEM (Security Information and Event Management)?
SIEM aggregates logs from every system in your environment — correlating events that individual tools see as noise into coherent attack patterns.
SIEM centralizes log collection and correlation — giving analysts a single view of security events across a complex environment.
Security Information and Event Management (SIEM) is a security platform that collects, aggregates, and analyzes log data from across an organization's environment — firewalls, servers, applications, endpoints, identity systems, and cloud services — in a centralized location. By correlating events from disparate sources, SIEM can surface attack patterns that would be invisible when looking at individual system logs.
SIEM was originally built for two purposes: compliance (aggregating and retaining logs required by regulatory frameworks) and detection (correlating events to identify suspicious activity). Modern SIEM platforms have expanded to include user and entity behavior analytics (UEBA), threat intelligence integration, and automated response playbooks. However, SIEM without skilled analysts to tune and operate it generates enormous volumes of noise and limited actionable detections.
What SIEM collects
- Authentication and access logs: successful and failed logins, privilege escalations, account modifications
- Network logs: firewall allow/deny decisions, VPN connections, proxy traffic, DNS queries
- Endpoint logs: Windows Event Log, Sysmon, EDR telemetry
- Application logs: web server access logs, database query logs, cloud service API logs
- Security tool logs: EDR alerts, IDS/IPS events, email security events
SIEM and compliance
Many regulatory frameworks require centralized log collection and retention. HIPAA requires audit controls and logging of access to electronic protected health information. PCI-DSS requires log management across the cardholder data environment. NIST CSF and CMMC both include logging requirements. SIEM is frequently the technical mechanism used to satisfy these requirements. SignalPoint's compliance advisory service helps organizations implement appropriate log management for their applicable frameworks.