A Business Logic Layer (BLL) is a typical software engineering artifact within a Multitier architecture.
A Business Logic Layer (BLL) is a typical software engineering artifact within a Multitier architecture. It separates the business logic from other tiers, such as the data access layer or service layer. BLL objects are typically partitioned into two categories: business process objects (those which reflect business activities, or behaviors) and business entities (those which reflect real world business objects). Business process objects are typically implemented as controllers, i.e. they contain no data elements and only expose behaviors and activities which represent business processes. Business entities typically correspond to entities in a domain model rather than a database model.
