OverviewBusiness Process Model and Notation (BPMN) is a standard for business process modeling that provides a graphical notation for specifying business processes in a ''Business Process Diagram'' (BPD), based on a flowcharting technique very similar to activity diagrams from Unified Modeling Language (UML). The objective of BPMN is to support business process management, for both technical users and business users, by providing a notation that is intuitive to business users, yet able to represent complex process semantics. The BPMN specification also provides a mapping between the graphics of the notation and the underlying constructs of execution languages, particularly Business Process Execution Language (BPEL). BPMN has been designed to provide a standard notation readily understandable by all business stakeholders, typically including business analysts, technical developers and business managers. BPMN can therefore be used to support the generally desirable aim of all stakeholders on a project adopting a common language to describe processes, helping to avoid communication gaps that can arise between business process design and implementation. BPMN is one of a number of business process modeling language standards used by modeling tools and processes. While the current variety of languages may suit different modeling environments, there are those who advocate for the development or emergence of a single, comprehensive standard, combining the strengths of different existing languages. It is suggested that in time, this could help to unify the expression of basic business process concepts (e.g., public and private processes, choreographies), as well as advanced process concepts (e.g., exception handling, transaction compensation). Two new standards, using a similar approach to BPMN have been developed, addressing case management modeling (CMMN, Case Management Model and Notation) and decision modeling, the (Decision Model and Notation).
ScopeBPMN is constrained to support only the concepts of modeling applicable to business processes. Other types of modeling done by organizations for non-process purposes are out of scope for BPMN. Examples of modeling excluded from BPMN are: * Organizational structures * Functional breakdowns * Data models In addition, while BPMN shows the flow of data (messages), and the association of data artifacts to activities, it is not a data flow diagram.
ElementsBPMN models are expressed by simple diagrams constructed from a limited set of graphical elements. For both business users and developers, they simplify understanding of business activities' flow and process. BPMN's four basic element categories are: ; Flow objects : Events, activities, gateways ; Connecting objects : Sequence flow, message flow, association ; Swim lanes : Pool, lane ; Artifacts : Data object, group, annotation These four categories enable creation of simple business process diagrams (BPDs). BPDs also permit making new types of flow object or artifact, to make the diagram more understandable.
Flow objects and connecting objects
Swim lanes and artifacts
Examples of business process diagrams
BPMN 2.0.2The vision of BPMN 2.0.2 is to have one single specification for a new Business Process Model and Notation that defines the notation, metamodel and interchange format but with a modified name that still preserves the "BPMN" brand. The features include: * Formalizes the execution semantics for all BPMN elements. *Defines an extensibility mechanism for both Process model extensions and graphical extensions. *Refines Event composition and correlation. *Extends the definition of human interactions. *Defines a Choreography model. The current version of the specification was released in January 2014.
Comparison of BPMN versions
Types of BPMN sub-modelBusiness process modeling is used to communicate a wide variety of information to a wide variety of audiences. BPMN is designed to cover this wide range of usage and allows modeling of end-to-end business processes to allow the viewer of the Diagram to be able to easily differentiate between sections of a BPMN Diagram. There are three basic types of sub-models within an end-to-end BPMN model: Private (internal) business processes, Abstract (public) processes, and Collaboration (global) processes: ;Private (internal) business processes: Private business processes are those internal to a specific organization and are the type of processes that have been generally called workflow or BPM processes. If swim lanes are used then a private business process will be contained within a single Pool. The Sequence Flow of the Process is therefore contained within the Pool and cannot cross the boundaries of the Pool. Message Flow can cross the Pool boundary to show the interactions that exist between separate private business processes. ;Abstract (public) processes: This represents the interactions between a private business process and another process or participant. Only those activities that communicate outside the private business process are included in the abstract process. All other “internal” activities of the private business process are not shown in the abstract process. Thus, the abstract process shows to the outside world the sequence of messages that are required to interact with that business process. Abstract processes are contained within a Pool and can be modeled separately or within a larger BPMN Diagram to show the Message Flow between the abstract process activities and other entities. If the abstract process is in the same Diagram as its corresponding private business process, then the activities that are common to both processes can be associated. ;Collaboration (global) processes: A collaboration process depicts the interactions between two or more business entities. These interactions are defined as a sequence of activities that represent the message exchange patterns between the entities involved. Collaboration processes may be contained within a Pool and the different participant business interactions are shown as Lanes within the Pool. In this situation, each Lane would represent two participants and a direction of travel between them. They may also be shown as two or more Abstract Processes interacting through Message Flow (as described in the previous section). These processes can be modeled separately or within a larger BPMN Diagram to show the Associations between the collaboration process activities and other entities. If the collaboration process is in the same Diagram as one of its corresponding private business process, then the activities that are common to both processes can be associated. Within and between these three BPMN sub-models, many types of Diagrams can be created. The following are the types of business processes that can be modeled with BPMN (those with asterisks may not map to an executable language): * High-level private process activities (not functional breakdown)* * Detailed private business process * As-is or old business process* * To-be or new business process * Detailed private business process with interactions to one or more external entities (or “Black Box” processes) * Two or more detailed private business processes interacting * Detailed private business process relationship to Abstract Process * Detailed private business process relationship to Collaboration Process * Two or more Abstract Processes* * Abstract Process relationship to Collaboration Process* * Collaboration Process only (e.g., ebXML BPSS or RosettaNet)* * Two or more detailed private business processes interacting through their Abstract Processes and/or a Collaboration Process BPMN is designed to allow all the above types of Diagrams. However, it should be cautioned that if too many types of sub-models are combined, such as three or more private processes with message flow between each of them, then the Diagram may become difficult to understand. Thus, the OMG recommends that the modeler pick a focused purpose for the BPD, such as a private or collaboration process.
Comparison with other process modeling notationsEvent-driven process chain, Event-driven process chains (EPC) and BPMN are two notations with similar expressivity when process modeling is concerned. A BPMN model can be transformed into an EPC model. Conversely, an EPC model can be transformed into a BPMN model with only a slight loss of information. A study showed that for the same process, the BPMN model may need around 40% less elements than the corresponding EPC model, but with a slightly larger set of symbols. The BPMN model would therefore be easier to read. The conversion between the two notations can be automated. Activity diagram, UML activity diagrams and BPMN are two notations that can be used to model the same processes: a subset of the activity diagram elements have a similar semantic than BPMN elements, despite the smaller and less expressive set of symbols. A study showed that both types of process models appear to have the same level of readability for inexperienced users, despite the higher formal constraints of an activity diagram.
WeaknessesThe weaknesses of BPMN could relate to: * ambiguity and confusion in sharing BPMN models * lack of support for routine work * lack of support for knowledge work, and * converting BPMN models to executable environments * lack of support for business rules and decision-making * lack of support for security/roles such as approval of a task * lack of support for resource constraints such as multiple tasks requiring a shared resource such as a workspace * lack of support for timed tasks * lack of support for stochastic tasks or tasks with uncertainty in time or quantity of resources to complete
BPEL and BPMNThe BPMN specification includes an informal and partia
See also* DRAKON * BPEL * Business process management * Business process modeling *Comparison of Business Process Model and Notation modeling tools * Decision Model and Notation * CMMN (Case Management Model and Notation) * Process Driven Messaging Service * Event-driven process chains * Function model * Functional software architecture * Workflow * Workflow patterns * Service Component Architecture * Decision Model and Notation (DMN) * XPDL * YAWL
Further reading* * Ryan K. L. Ko, Stephen S. G. Lee, Eng Wah Lee (2009) Business Process Management (BPM) Standards: A Survey. In: Business Process Management Journal, Emerald Group Publishing Limited. Volume 15 Issue 5. ISSN 1463-7154