Complex Event Processing
Summary: An approach to stream-processing that focuses on identifying specific sequences or patterns of events across a stream.
Sources: chapter11
Last updated: 2026-04-18
Core Idea
Complex Event Processing (CEP) allows users to specify patterns of interest using a declarative query language (like SQL) or a graphical interface. The CEP engine maintains a state machine that tracks the stream and emits a “complex event” when a pattern is matched.
Comparison with Stream Analytics
- Stream Analytics: Focused on aggregations and statistical metrics (e.g., averages, rates) over time windows.
- CEP: Focused on finding specific sequences of individual events (e.g., “Event A followed by Event B within 5 minutes, but without Event C occurring in between”).
Use Cases
- Intrusion Detection: Finding patterns of network activity that suggest a security breach.
- Algorithmic Trading: Executing trades when specific market conditions are met.
- Manufacturing: Detecting a sequence of sensor readings that indicates a machine is about to fail.