Information models are made up of things that we call entities, characteristics of those things , called attributes, and the relationships among the entities. Entities are identified by a name. Each entity is uniquely identified by a key-attribute . Additional attributes may be needed to further describe the entity. A strong relationship between the information model and the function model should exist.
Entities come from the lines joining the activities on the function model.
The two models validate each other, and the building of each should be an iterative process. IDEF can be used for a wide range of applications and requires minimal training. Modeling is an iterative process. The first attempt need not be perfect. Subsequent iterations of the analysis will continue to improve the model at all levels.