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Chapter 3


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Chapter 3

  1. 1. 2/28/2013 2Business Process Methodology CHAPTERS’ OBJECTIVESChapter 3Business Process Modeling Foundation • the foundation of business process modeling by investigating: ▫ abstraction concepts, and ▫ introducing the main sub-domains of business Prepared by: Rao Majid Shamshad process modeling, namely: University of Education, Lahore  modeling functions, email:  processes, http://  data,  organization,  and operation. 3 4Business processes activities MANUAL ACTIVITIES• Business processes consist of activities whose • Manual activities are not supported by information coordinated execution realizes some business systems. An example of a manual activity is sending goal. These activities can be: a parcel to a business partner. ▫ System activities, ▫ user interaction activities, ▫ manual activities. 1
  2. 2. 2/28/2013 5 6User interaction activities MANUAL + USER INTERACTION ACTIVITIES• These are activities that knowledge workers • Some activities that are conducted during the perform, using information systems. enactment of a business process are of manual• Humans use IS to perform these activities, nature, but state changes are entered in a application with appropriate user interfaces business process management system by means need to be in place to allow effective work. These of user interaction activities. applications need to be connected to back-end • e.g. delivery of a parcel can be monitored by an application systems that store the entered data IS. Typically, the actual delivery of a parcel is and make it available for future use. acknowledged by the recipient with her signature. 7 8 SYSTEM ACTIVITIES • System activities do not involve a human user; they are executed by information systems. ▫ An example of a system activity is retrieving stock information from a stock broker application or checking the balance of a bank account. It is assumed that the actual parameters required for the invocation are available. • If a human user provides this information, then it is a user interaction activity. Both types of activities require access to the respective software systems. 2
  3. 3. 2/28/2013 9 10WORKFLOW TECHNOLOGY “IS-A” RELATIONSHIP• Certain parts of a business process can be • is-a or is_a or is a (subsumption) is a enacted by workflow technology. relationship where one class D is a subclass of• A workflow management system can make sure another class B (and so B is a superclass of D). that the activities of a business process are • In other words, "D is a B" (B subsumes D, or D is-subsumed-by B) usually means that concept D performed in the order specified, and that the is a specialization of concept B, and concept B is information systems are invoked to realize the a generalization of concept D. For instance, a business functionality. "fruit" is a generalization of "apple", "orange",• No “is-a” relationship. "mango" and many others. One can say that an apple is a fruit. 11 123.2 ABSTRACTION CONCEPTS 3.2.1 HORIZONTAL ABSTRACTION• To capture the complexity in business process • Along the lines of the levels of abstraction management, different abstraction concepts are identified by the Object Management Group, the introduced. meta-model level, the model level, and the• A traditional abstraction concept in computer instance level play important roles in the design science is the separation of modeling levels, and analysis of complex systems in general and from instance level to model level to meta-model software systems in particular. level, denoted by horizontal abstraction. • It is instructive to explain these levels in a bottom-up order, starting with the instance level. 3
  4. 4. 2/28/2013 13 14INSTANCE AND MODEL LEVEL • For instance, a set of similar business process instances are classified and represented by a• The instance level reflects the concrete entities business process model. In object modeling, a that are involved in business processes. set of similar entities is represented by a class, Executed activities, concrete data values, and and in data modeling using the Entity resources and persons are represented at the Relationship approach, a set of similar entities is instance level. represented by an entity type, and similar• To organize the complexity of business process relationships between entity types are scenarios, a set of similar entities at the instance represented by a relationship type. level are identified and classified at the model level. 15 16MODEL AND META-MODEL• Models are expressed in meta-models that are associated with notations, often of a graphical nature.• In data modeling, the Entity Relationship meta- model defines entity types, relationship types, and connections between them. Typical graphical notations of the Entity Relationship meta-model are rectangles for entity types and diamonds for relationship types, connected by lines. 4
  5. 5. 2/28/2013 17 183.2.2 VERTICAL ABSTRACTION• Vertical abstraction in business process modeling is that where distinct modeling sub- domains are identified. As depicted, process modeling is at the centre of the modeling effort, because it also integrates the modeling efforts that are conducted in the other sub-domains. 19 20 3.3 FROM BUSINESS FUNCTIONS TOSUB-DOMAINS BUSINESS PROCESSES• Function modelling, data modelling, • Value chains provide a high-level organization of organization modelling, and modelling of the the functions that an enterprise performs. To operational information technology landscape provide a more detailed view, these top-level are required to provide a complete picture of a business functions are broken down to functions business process. While these subdomains are of smaller granularity and, ultimately, to the most important ones, additional sub- activities of operational business processes. domains can be defined if they are relevant. • Functional decomposition is the technique of choice. 5
  6. 6. 2/28/201321 22 REPRESENTATION OF MODEL • business functions are represented by rectangles, while functions of the finest granularity are represented by rectangles with rounded corners. • Functions at the leaf level of the functional decomposition are also called activities.23 24 • The sample business process starts with analyzing the order, and then conducting either a simple check or an advanced check depending on the decision made during process execution. • Events play a crucial role when interrelationships between business processes are expressed. 6
  7. 7. 2/28/2013 25 26 DEFINITION 3.1 • A functional decomposition of coarse-grained business functions to fine-granular activities defines the functional perspective of a business process 27 28Granularity • The terms granularity, coarse, and fine are• Granularity is the extent to which a system is broken relative, used when comparing systems or down into small parts, either the system itself or its descriptions of systems. An example of description or observation. It is the "extent to which a larger entity is subdivided. For example, a yard broken increasingly fine granularity: a list of nations in into inches has finer granularity than a yard broken into the United Nations, a list of all states/provinces feet." in those nations, a list of all counties in those• Coarse-grained systems consist of fewer, larger states, etc. components than fine-grained systems; a coarse- • The terms fine and coarse are used consistently grained description of a system regards large across fields, but the term granularity itself is subcomponents while a fine-grained description not. For example, in investing, more granularity regards smaller components of which the larger ones are refers to more positions of smaller size, while composed. photographic film that is more granular has fewer and larger chemical "grains". 7
  8. 8. 2/28/2013 29 303.4 ACTIVITY MODELS AND ACTIVITY INSTANCES • activity models can be expressed in different forms, for instance, by plain text• Business functions provide a high-level, coarse- or by some formal specification or grained representation of the work conducted by references to software components that enterprises. Activities can be found in the leaves of the functional decomposition. implement them.• An activity model describes a set of similar • Activity instances represent the actual activity instances, analogously to a process work conducted during business model describing a set of process instances with processes, the actual units of work. the same structure. While process models are typically expressed in graph-like notations 31 32 8
  9. 9. 2/28/2013 33 34STATE OF TRANSITION 3.5 PROCESS MODELS AND PROCESS INSTANCES 35 363.5.1 PROCESS MODELS • Edge: Directed edges are used to express the relationships between nodes in a process model.• Any modelling effort starts with identifying the main • Node: A node in a process model can represent concepts that need to be represented. In metamodelling, the concepts to be represented are an activity model, an event model, or a gateway models. model.• Process Model : A process model represents a blue print for a set of process instances with a • Activity Models: Activity models describe similar structure. Process models have a two-level units of work conducted in a business process. hierarchy, so that each process model consists of a Each activity model can appear at most once in a set of activity models. Nesting of process models within process models is not represented, because it process model. No activity model can appear in would introduce complexity that is not required. multiple process models. Each process model consists of nodes and directed edges. 9
  10. 10. 2/28/2013 37 38• Event models: Event models capture the occurrence of states relevant for a business process. Process instances start and end with events, so process models start and end with event models.• Gateway Models: Gateways are used to express control flow constructs, including sequences, as well as split and join nodes. 39 40• The next step in modelling concerns the • Each node is associated with at least one identification and formalization of the edge. The different types of nodes are relationships between these concepts. Figure 3.14 provides a representation of the concepts represented by the generalization relation. and their relationships by a structure diagram, Activity models reflect the work units to be defining a process meta-model. performed, event models represent the• Each process model consists of nodes and edges. occurrence of states relevant for the The nodes represent activity models, event business process, and gateway models models and gateway models, while the edges represent execution constraints of represent control flow between nodes. Each edge activities, such as split and join nodes. is associated with exactly two nodes, relating them in a particular order. 10
  11. 11. 2/28/2013 41 42While the association between nodes and • Figure 3.15 shows a process model based on theedges are defined at the node level, the process meta-model introduced. The notationcardinality of the association between special used to express this process model is taken fromtypes of nodes (activity models, event models, the Business Process Modeling Notation:and gateway models) differs. Each activity • Event model nodes are represented by circles;model has exactly one incoming and one the final event model is represented by a boldoutgoing edge. circle. • Activity models are represented by rectangles with rounded edges. • Gateway models are represented by diamonds. • Edges are represented by directed edges between nodes. 43 443.5.2 PROCESS INSTANCES • A process instance consists of a number of activity instances as well as event and gateway instances. The ordering relationships of activity• Process models define restrictions on process instances in a process instance is defined by the instances that belong to the process model. relationships of the activity models in the Therefore, it is essential to properly define not process model. only process models but also process instances. • For instance, if a process model defines an Modelling process instances is not an easy task, execution ordering constraint between activity because of their intangible nature. A process models A and B, then for each particular process instance is started, and it lives for a limited time instance, the activity instance that belongs to period before it ceases to exist, similarly to activity model A must have terminated before activity instances. the activity instance for B can be started. 11
  12. 12. 2/28/2013 45 46• Each process instance is associated with exactly • In the case of loops, an activity model is one process model, and each process model is associated with multiple activity instances. An associated with an arbitrary number of process activity model that lies on a branch that is not instances. Each process instance is composed of taken during a particular process instance is not an arbitrary number of activity instances. Each associated with any activity instance, explaining activity instance is associated with exactly one the cardinality of the association * that allows activity model. The same holds for events and zero occurrences of the association, i.e., there gateways. might be activity models in a process model for• Note that each activity model is associated with which no activity instances are required for a an arbitrary number of activity instances. particular process instance. 47 48 3.6 PROCESS INTERACTIONS • enterprises cooperate with each other, it is essential to consider the interaction between enterprises. • Since all activities that an enterprise conducts are part of some business process, the interaction between enterprises can be described by the interaction of business processes of these enterprises. 12
  13. 13. 2/28/2013 49 50These interactions typically occur in a peer-to-peer style, following an agreed-upon processchoreography. EVENT DIAGRAM 51 523.7 MODELLING PROCESS DATA 3.7.1 MODELLING DATA • Data modelling is at the core of database design.• Business processes operate on data. Explicitly The Entity Relationship approach is used to representing data, data types, and data classify and organize data in a given application domain. dependencies between activities of a business • In a modelling effort, the most important process puts a business process management entities are identified and classified. Entities are identifiable things or concepts in the real world system in a position to control the transfer of that are important to the modelling goal. In the relevant data as generated and processed during sample scenario, orders, customers, and products are among the entities of the real world processes enactment. that need to be represented in the data model. 13
  14. 14. 2/28/2013 53 54• Entities are classified as entity types if they have • The entities classified in an entity type need to the same or similar properties. Therefore, orders have similar, but not identical structure, because are classified by an entity type called Orders. attributes can be optional. If the application Since each order has an order number, a date, a domain allows, for instance, for an order to have quantity, and an amount, all order entities can or not to have a discount, then the amount be represented by this entity type. Properties of attribute is optional. This means that two orders entities are represented by attributes of the are classified in entity type order even if one has respective entity types. a discount attribute while another does not. 55 56REPRESENTATION OF ER MODEL 3.7.2 WORKFLOW DATA PATTERNS• Entity types in the Entity Relationship meta- • To organize data-related issues in business model need to be represented in a notation by a process management, workflow data patterns particular symbol. While there are variants of have been introduced. Workflow data patterns Entity Relationship notations, entity types are formulate characteristics on how to handle data often represented by rectangles, marked with the in business processes. They are organized name of the entity type. Figure 3.24 shows an according to the dimensions data visibility, data entity type Orders at the centre of the diagram. interaction, data transfer, and data-based Other entity types in the sample application routing. domain are customers and products. The attributes are represented as ellipsoids attached to entity types. 14
  15. 15. 2/28/2013 57 58• Data visibility is very similar to the concept of • Workflow data: The data object is visible to all scope in programming languages because it activities of a given business process, but access characterizes the area in which a certain data is restricted by the business process object is available for access. The most management system, as defined in the business important workflow data patterns regarding process model. data visibility are as follows.• Task data: The data object is local to a • Environment data: The data object is part of particular activity; it is not visible to other the business process execution environment; it activities of the same process or other processes. can be accessed by process activities during• Block data: The data object is visible to all process enactment. activities of a given subprocess. 59 60DATA INTERACTION PATTERNS DATA TRANSFER• Data interaction patterns describe how data • Data transfer is the next dimension to objects can be passed between activities and consider. Data transfer can be performed by processes. Data objects can be communicated passing values of data objects and by passing between activities of the same business references to data objects. These data process, between activities and subprocesses transfer patterns are very similar to call-by- of the same business process, and also value and call by- reference, concepts used in between activities of different business programming languages to invoke processes. Data can also be communicated procedures and functions. between the business process and the business process management system. 15
  16. 16. 2/28/2013 61 62 • The levels of abstraction in organization3.8 MODELLING ORGANIZATION modelling are shown in Figure 3.25. As in process modelling and data modelling, the meta- model level provides the means to express• An important task of a business process models, in this case organizational models. management system is the coordination of • Concepts at this level are positions, roles, teams, work among the personnel of an enterprise. and relationships between positions like To fulfill this, the system has to be provided supervisor. In organization modelling, there are with information on the organizational a few formal rules on how to express structures in which the business process will organizational structures, as well as notations to execute. express them. 63 64 • Sample Organizational chart 16
  17. 17. 2/28/2013 65 66• Each work item is associated with exactly one RESOURCE ALLOCATION activity instance. When a knowledge worker • The assignment of process participants to completes the activity instance, the business activities in a business process can be classified process management system is informed, so that by resource patterns. the process instance can be continued • Direct Allocation: In direct allocation, an accordingly. individual person, rather than a position in an• In order to discuss the resource allocation organization, is allocated to all activity instances principles, a state transition diagram of work of a particular activity model. This resource items is considered, and a relationship of activity allocation is useful in cases where there is instances to the respective state transitions is exactly one person who is suitable for provided. performing these activities, such as the chairperson of a company, who has to finally decide on investments exceeding a certain threshold. 67 68• Role-Based Allocation: Role-based allocation • The mapping of role information to specific is the standard way of allocating work to the knowledge workers is called role resolution. members of organizations. It is based on the Current information on the availability of the understanding that all members of a certain role knowledge worker is used during role resolution. are somehow functionally equivalent, so that any • There are two ways of realizing role-based member of the role can perform a given unit of allocation. work. 1. when an activity instance enters the ready state,• To each activity model in a business process the work item is communicated to the members model, a role is assigned, indicating that all of the group. Once one member of the group members of the role are capable of performing selects a work item, the work items associated the respective activity instances. with the other group members are deleted. 17
  18. 18. 2/28/2013 69 702. only one person is selected to perform the 2. by role resolution at run time of the business activity instance, so only one work item is created. process, only available persons are selected to• Advantages of roll base allocation perform activities. This approach avoids situations1.The business process model does not need to be in which persons are selected to perform activity changed when there are changes in the personnel, i.e., employees retire and new instances that are currently not available, for employees are hired. When using direct instance, due to meetings or absence. In direct role allocation, any change in the personnel related resolution, when the person is not available, there is to the directly allocated persons would result in a change in the business process model. no way of continuing the business process. 71 72• Deferred Allocation: In deferred allocation, • Authorization: Authorization allocates the decision about who performs an activity persons to activity instances based on their instance is only made at run time of the business positions. So, a list of positions is enumerated process. To this end, there is no distinction that specifies the persons who can perform the between deferred allocation and role-based activity instance. This could also be achieved by allocation. However, in deferred allocation, adding a new role that captures the rather than using the role information defined authorization. during design time, the allocation is performed • A specific type of authorization that uses as an explicit step in the business process, and capabilities of the knowledge worker to perform not influenced by role information. allocation is also possible. 18
  19. 19. 2/28/2013 73 74• Separation of Duties: The separation of • Case Handling: In the case handling allocation duties allocation scheme relates different scheme, certain activities in a business process allocations within one business process. For require an understanding of the overall case. In instance, a document needs to be signed and these environments, it is useful that the same countersigned by two employees with a common knowledge worker deals with all activities of one role. In role-based allocation, these activities business process instance. This avoids errors could be performed by the same employee. and reduces processing time, because the Separation of duties allows relating allocations knowledge worker already knows the case, and in a way that this is ruled out, so that each so can solve the issues at hand more efficiently document is signed by two different employees. than a colleague to whom the case is not known. 75 76• History-Based Allocation: The idea of • While this is not part of a role specification, this history-based allocation is that a person is information needs to be represented in the allocated to an activity instance based on what business process management system so that it this person worked on previously, i.e., on the can decide on the allocation based on the history history of the activity instance that he or she and personal experiences. This allocation completed. This includes other business process scheme is useful for realizing a “one face to the instances. The goal is to allocate work to persons customer” strategy, in which for each customer according to their personal experiences and there is a dedicated individual responsible for all expertise that is not represented in the role aspects of communication with it. information. 19
  20. 20. 2/28/2013 77 78• Organizational Allocation: If organizational 3.9 MODELLING OPERATION allocation is used, not roles but the positions • During the enactment of human interaction within the overall organization are used to workflows, knowledge workers perform activity allocate activity instances. For instance, to instances. When a knowledge worker starts working authorize expenditure, the manager of the on a specific activity, the respective application organizational unit that requested the program is started, and the input data as specified in expenditure needs to approve. Depending on the the process model is transferred to that application program. When the knowledge worker completes particular language used to express that activity, the output data generated is collected organizational allocation, complex allocation in the output parameters. These parameter values rules can be realized, all of which take advantage can then be stored in the application program. They of the organizational structure of the company. can also be transferred by the business process management system to the next activity, as specified in the business process model. 79 80• The heterogeneous nature of information • The operational perspective includes: technology landscapes led to various kinds of ▫ invocation environment of application interface definitions, most of which did not programs, prove to be compatible. With the advent of ▫ the definition of the input and output parameters service-oriented computing, the operational of the application program, aspects of business processes are represented by ▫ and their mapping to input and output services, providing the required uniformity. parameters of business process activities. • Therefore, functional requirements need to be detailed in order for us to evaluate whether a certain software system provides the required functionality in the context of a business process. 20
  21. 21. 2/28/2013 81 82• This perspective is not limited to functional 3.10 BUSINESS PROCESS FLEXIBILITY requirements. Non-functional requirements also • The quest for flexibility can be regarded as the need to be represented, for instance, security main driving force behind business process properties and quality of service properties of management, both at an organizational level, the invoked applications or services, such as where strategic business processes are execution time and uptime constraints. In investigated, and at an operational level, where service-oriented architectures, these properties human interaction workflows and system are typically specified in service-level workflows are important concepts for realizing agreements between collaborating business business processes. partners. These service-level agreements are • According to Wikipedia, flexibility refers to the part of a legal contract that the parties sign. “ability to easily bend an object or the ability to adapt to different circumstances.” 83 84• In today’s dynamic market environments, • Different aspects have to be taken into account “different circumstances” are induced by when considering flexibility. First of all, changes in the market environment of the flexibility is provided by explicit representation company. Business processes are objects that of business processes, because adaptations of need to adapt easily to changes. Since products explicit, graphically specified business processes that companies provide to the market are is much easier than adaptation of written generated by business processes, flexible organizational procedures or business policies business processes are an important asset for buried in software code. coping with market changes in an effective manner. 21
  22. 22. 2/28/2013 85 86• In typical workflow environments, such as Explicit Process Representations system workflows and human interaction • Business process management systems are workflows, information systems are required for created to narrow the gap between business enacting workflow activities. The interfaces to goals and their realization by means of these systems might be hardcoded in the information technology. The main way to adapters of the workflow management system. provide this flexibility is based on explicit In dynamic software landscapes, where representations of business processes at functionality is provided through standardized different levels. While organizational business interfaces, the ability to change the binding of processes have a coarse-grained structure and are typically specified textually by forms, particular software to workflow activities is operational business processes consist of process another source of flexibility. activities, and execution constraints that relate them. 87 88 This process features a sequence of activities,• Explicit process representations provide where the first activity to store the order is flexibility, since changes to the current process preceded by a start event. After the order is can be discussed and agreed upon by the stored the inventory is checked. This version of different stakeholders involved in the design of the business process rules that the shipment is the business process. In this context, flexibility is prepared only after the invoice is sent and the achieved by changes at the business process funds are received. Finally, the goods are shipped model level that are immediately translated to and the process terminates. actual business process instances. 22
  23. 23. 2/28/2013 89 90 Discussing the problem of the process• Due to the somewhat cautious policy realized by the business process— prepare shipment only instances, the stakeholders find out that after receiving the funds—business process concurrency can be exploited within the instances based on this process model might process. If activities can be executed suffer from long processing times, resulting in concurrently, their order of execution is insufficient customer satisfaction. irrelevant.• In order to solve this problem, the process owner starts a review of this business process by inviting process participants and process consultants to a joint workshop. The business process model is used as a communication platform for these stakeholders at this workshop. 91 92 • By associating roles with activity models atOrganizational Modelling design time and mapping roles to personnel that is skilled, competent, and available to perform• In the case of human interaction workflows, the the activity at run time, flexibility is improved, enactment environment of the business process because changes in the personnel structure of has to take into account the organizational the organization do not affect the business structure of the company that runs the business processes. process. Flexibility in organizational modelling • For instance, absent knowledge workers are not is achieved by assigning roles to process with associated with specific activity instances, activities, and not to specific individuals. as are persons who are currently available. 23
  24. 24. 2/28/2013 93 94• Thereby, the dynamic aspect in the organization—knowledge workers might be temporarily absent or there might be changes in the work force—can be represented at the model level. Consequently, changes in the personnel are hidden from the process, as long as the roles defined in the model can actually be filled by persons in the organization. 95 96 • There are different options for selecting aSelection of Business Partners in particular shipper. The selection can be doneProcess Choreographies before a particular process instance starts. This• Consider a business process choreography with alternative is useful if sufficient information on multiple business partners, each of which plays a the goods to be shipped is available before the specific role in the choreography. If there is a process starts. role Shipper specified according to the • In scenarios where only during run time of the requirements for shipping goods, it can be process instance are the goods and the sender bound to specific enterprises that can perform and receiver determined, the dynamic selection the work. Additional flexibility is gained because of a shipper is useful. Based on the information the organizations participating in a on the shipment and on its additional choreography are not hardwired, but represented at the model level. properties—such as dangerous goods—an appropriate shipper can be selected at run time. 24
  25. 25. 2/28/2013 97 98 Standardized Software Interfaces • Standardized interfaces to existing software systems are another means of flexibility in business process management. A variety of techniques to specify software interfaces are known from software engineering and software architectures. It is a key concept to decouple the use of a software component from its implementation, i.e., to hide implementation details from usage information, following the information hiding principle. 99 100• In the context of business process management, standardized software interfaces are of crucial importance in system workflows, and also in human interaction workflows, since the overall process structure can be decoupled from the implementation of particular activities realized by software components.• There are two variations: the software system realizing a particular activity can be defined at design time of the process or at run time of the process instances. 25
  26. 26. 2/28/2013 101 1023.11 ARCHITECTURE OF PROCESS • Business Process Environment: TheEXECUTION ENVIRONMENTS business process environment triggers the instantiation and enactment of process instances• The architecture model contains: based on process models.• Business Process Modelling: The business process modelling subsystem is used for creating • Business Process Model Repository: The business process models, containing information business process model repository holds on activities, their operations, and the structure business process models that are created by the of the business process. This architecture business process modelling component. subsystem can be realized by business process modelling tools. 103 104• Process Engine: The process engine is • Service Providers: Service providers host responsible for instantiating and controlling the application services that realize business process execution of business processes. It is the core activities. In the architecture model, service component of a business process management providers represent an abstract entity that system. This component is triggered by the subsumes not only Web service providers but business process environment. It uses process also knowledge workers that realize particular models to instantiate and control the enactment activities in business processes. The of process instances. To execute a particular organizational and technical information that activity instance, it calls entities that act as the process engine needs in order to determine providers of the required functionality. In a and access the service provider is also stored in service-oriented architecture, service providers the business process model repository. are called to execute individual services that realize business process activities. 26