Gartner’s IT Glossary defines CEP as follows:
WSO2 SP allows you to detect patterns and trends for decision making via Patterns and Sequences supported for Siddhi.
Patterns
Siddhi patterns allow you to detect patterns in the events that arrive over time. This can correlate events within a single stream or between multiple streams. A pattern can be a counting pattern that allows you to match multiple events received for the same matching condition, or a logical pattern that match events that arrive in temporal order and correlate them with logical relationships.
For more information, see Siddhi Query Guide - Patterns.
Sequences
This allows you to carry out analysis based on the sequential order in which events matching certain conditions arrive. The difference between sequences and patterns is, in Siddhi sequence, events arriving consecutively are compared based on given conditions. For patterns, events do not have to arrive in consecutive manner.
For more information, see Siddhi Query Guide - Sequence.