Filters can be added to a GeoEvent Service to perform real-time filtering of GeoEvents based on a specified set of conditions. In GeoEvent Manager, you can add filters to a GeoEvent Service by dragging and dropping a filter element from the element tray onto the canvas or by double-clicking the filter element—in either case, a properties dialog will open, allowing you to configure the filter.
See What are filters? to learn more about the filtering capabilities available with GeoEvent Server.
Step-by-step instructions illustrating how to add filters to a GeoEvent Service can be found in the Introduction to GeoEvent Server tutorial. Access the tutorial from GeoEvent Server tutorials.