Glossary · System coordination, integration and orchestration
Earliest due date (EDD)
Also known as: EDD rule, earliest due date first
German: Frühester Fälligkeitstermin (EDD)
In production scheduling, earliest due date (EDD) is a dispatch rule that processes waiting jobs in order of their due dates, starting with the job due first. On a single machine it minimizes the maximum lateness of the jobs.
- System integration
In one sentence
Earliest due date is a dispatch rule that processes jobs in order of their due dates, which minimizes maximum lateness on a single machine.
Example
The laser cutter's queue is sorted by customer due date, so an order due tomorrow is cut before an order that arrived earlier but is due next week.
How it applies
- Operation: EDD is easy to explain and supports delivery reliability. It ignores setup times and processing times, so it can create many changeovers or delay short jobs behind long ones.
- Engineering: In the MES, EDD is often combined with other criteria, such as grouping by setup family within a due-date window. Due dates must be maintained correctly in the source system for the rule to work.
- Documentation: Scheduling documentation should state which due date is used (customer, internal or operation due date) and how ties and rush orders are handled.
EDD vs. FIFO
First in, first out (FIFO) processes jobs in arrival order, which is fair and predictable but ignores urgency. EDD reorders by due date and therefore needs reliable due dates.