# Edge-finding

### From Glossary

The edge-finding rule is a constraint propagation technique that consists of deducing whether an activity can, cannot, or must be executed before or after a set of activities that all (including ) require the same resource. Two types of conclusions can then be drawn: new ordering relations (“edges” in the graph representing the possible orderings of activities) and new time-bounds (i.e., tightening of the earliest and latest start and end times of activities).

An edge-finding algorithm is a procedure that performs all such deductions.