Splunk is one of the leading SIEM solutions in the market that provides the ability to collect, analyze and correlate the network and machine logs

Splunk ingests machine data (logs, events, metrics), parses and indexes it, and makes it searchable so analysts can monitor, detect, investigate, and report incidents.

Simple flow:

Forwarder (agent) → Indexer (parse & store) → Search Head (run SPL, build dashboards/alerts) → Outputs/Actions (email, webhook, ticket).

Core components

Splunk Forwarder

A lightweight agent installed on endpoints to collect and forward data to Splunk. It’s low overhead and recommended for production ingestion.

Common sources:

• Web servers (HTTP logs)
• Windows machines (Event Logs, PowerShell, Sysmon)
• Linux hosts (syslog, application logs)
• Databases (connection logs, errors)

Indexer

Parses incoming data (timestamps, line breaking), normalizes into field-value pairs, and stores events in indexes (hot → warm → cold → frozen). Indexers also answer search requests.