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BPMDS'00 |
Prepared by Ilia Bider for brainstorming session of the 2nd BPMDS workshop (BPMDS'00)
New BP resources http://processplatsen.ibissoft.se/en/node/29
The goal with this document is to gather and systemize the basic notions that will allow us to talk about business processes in a structured way. Most of the notions that may be needed are already defined somewhere, for example, in the BPR (Business Process Reengineering) literature, Workflow standards, or are in the air. Thus, we do not need to invent everything, rather to collect what is required. The purpose of our work is to lay a foundation for creating a model that can be interpreted by a computer in order to support business processes. This aim is (slightly?) different from what BPR is aimed at (mostly, process improvement), see the note below. Thus, the resulting system of notions may not be equal to the one used in BPR, and we might need to define additional notion/or view the existing notions in some nontraditional way.
Notes:
According to the BPR literature (see for example [1,2]), a business process can be viewed as a set of partially ordered activities intended to reach a goal. The example of goals are:
The above definition, beside the notion of business process, introduces the following notions:
The notion of objective (goal) presumes that at any moment of the interval of time when the process exists we can tell whether the process's objective is achieved or not. If it is not achieved, we would like to be able to tell how far it is to the process's goal. This leads us to the notion of the process's state. The state can be final (stable?), if the objective has been reached, or intermediate (unstable?), otherwise. As an example, various states of a "house building" process are illustrated on Figure 1.
To be able to discuss the state of the process without viewing all the time the process development in the real world, we need to have some way to represent the process's state on a piece of paper, in the computer, etc. This leads us to the notion of state representation. For example, for the house building process from Figure 1, the state may be represented as a snapshot of the house under construction and everything around it. Alternatively, it may be a 3-dimensional image, etc. Where it does not cause a confusion, it is possible to refer to state representation as to state. This is especially applicable to the processes that do not deal with production of physical objects, e.g., a sales process aimed to closing a deal. For those kind of process, the state is always an abstract construct which is difficult to differentiate from the state representation.
The notion of state can help us to define the notion of activity. An activity can be viewed as an action (a set of actions?) aimed at changing the process state in a special way.
The definition of activity above is based on the notion of change in the process state. Such change can happen not only as a result of completing an activity, but in many other, often non-anticipated, ways. For example, a wall in the building process from Figure 1, can be destroyed by an act of sabotage, an earthquake, etc. Some of the program code written in the frame of a software project can be lost during a disk crash, etc.
A moment of time when the process's state changes may be called an event in the process's lifetime. Each completed activity results in an event. But as was pointed above, events can happen unpredictably too.
Consider all the process's events up till now (a point of observation). The sequence of these events composes an internal time of the process (as nothing happens between events). A sequence of process's state after each event forms the history of the process evolution.
Note. We consider that two real events cannot happen at the same time, but they are separated from each other by some interval of time, however small it is. This assumption has no practical implications, but it simplifies the analysis .
Any business deals with many processes going in parallel. Thus, it is often of interest to relate the internal time of each process to the external time that is common to all processes. This can be done by having a record for each event that fixes the external time of this event. We can call such record a registered event, or r-event for short. Beside external time (time stamp), we can put in r-event other information that connects the (internal) process event to the external world. This may include, cause of event (activity execution, earthquake, etc.), participants of the event, the registrar, his comments on the event, etc. A chronological sequence of events registered in the frame of the process, forms a chronicle, i.e., the written history of this process.
The notion of business process which was discussed above refer to the concrete process that evolves in time. Processes that have similar goals, and similar patterns of behavior (the same kind of activities) can be united by the notion of process type. Examples of the process types are sales process, manufacturing process (concerns a particular product), etc. Very often, the term business process is used to refer to the process type. In the contexts where it is not clear if the term business process refer to the type or to the concrete process, the term process instance can be used as opposite to the process type.
The above notions allow us to consider a business process as a dynamic system which moves in the space of all possible process states until it reaches the final state (the objective). Such systems possesses both proactive and reactive behavior. They are (pro)active because execution of each activity normally happens not as a reaction on the signal from outside, but rather because of the internal logic of the process evolution. They are reactive as external events can require the system to react on them, e.g., by rebuilding the wall destroyed by an earthquake.
The mixture of reactive and proactive behavior makes it impossible to define the process's objective just as a point in the process state, compare, for example, the first and the last slides in Fig. 1. The objective should rather be defined as a set of final states with a criterion of which final states are reachable, and which ones can be considered as nearest to the given intermediate state. If the unpredicted external event moves the process backwards or sidewards, the initially projected final state might become unreachable, but another one can become reachable instead.
The resulting list of basic notions looks like (in alphabetic order):
Activity
Business process
Change
Chronicle
Event
History
Objective
State
Time
A business process’s participants can be roughly classified in three categories: artifacts, human beings, and organizations.
A notion of artifact is used to represent any physical or abstract object like document, product, computer program, etc. The role of a particular artifact in various processes can vary from being a passive object produced during the process to an active tool used for executing activities in the process. Artifacts can have a complex structure, e.g., an artifact can have other artifacts included as its constituents, or it can have some other type of associations with other artifacts.
A concept of human being represent a person participating in the process. The role of the person can vary from being an active participant executing activities, a relatively passive communication partner, or even a passive object to which the process’s activities are directed, e.g., a patient in the hospital.
Very often, human beings participate in a business process not on their own, but on behalf of some organization, like company, political party, department, team, etc. People connected to a particular organization and participating on behalf of it in business processes can be called members. Members can be connected to the organization via employment contracts, actual membership, etc. Membership can be permanent or temporal (a contract employment, for example). Each member has its own role in relation to a particular type of business processes. The same person can be a member in several organizations. Moreover, the same person may have several roles in the same organization.
Organizations may have relations between each other that last longer than the time of any particular business process. These relation can be of various types, e.g. ownership relation, cooperation, customer/vendor etc.
Artifacts, human beings and organizations may have various roles in a particular business process. The most important roles are defined below.
In respect to a particular process, organizations fall into two categories, the owner of the process, and external organizations. Members of the owner become the staff who complete activities in the frame of the process. Members of the external organizations become the contacts who participate in various communication activities.
The internal participants, i.e. staff, are the driving force of the process. They are responsible for planning and executing activities. The contacts serve only as counterparts in communication activities, e.g. send a letter to X, phone Y, etc. Even when a counterpart is expected to react, like send a reply, or return a phone call, it is a member of staff, who is responsible for this event to happened. He must send a reminder, or ring himself, if the counterpart is not responding in time.
A particular member of the staff may be assigned to be a supervisor of a particular process instance. Being a supervisor does not mean that the person who plays this role needs to control the process in all details. He is merely responsible to solve the problems if and when they arise in the frame of this particular process (instant).
A process’s subject (topic) is something that the process’s activities are directed at. The subject may be an artifact, a human being, or an organization, or a combination of all of them. An artifact as a subject may represent a product that we sell, buy or manufacture during the given process. A human being may regarded as a subject of a hospital process aimed at curing him. An organization may serve as subject of the process aimed at changing its structure in order to make the organization more effective.
A process’s beneficiary is an organization or a person in whose interests the process is driven. A beneficiary is often referred to as a customer. The beneficiary can be an external organization (i.e. an external customer), or may coincide with a process owner (internal customer). There can be more than one beneficiary in a particular process. For example, in the purchase process the primary beneficiary is a person or organization that receives goods/ services. However, the vendor also benefits from making money from this purchase. The beneficiary can coincide with the process owner, e.g., in case of a purchase process, or even with the subject, e.g., in case of a patient in the hospital.
To complete various activities in the frame of a process, various kind of tools, materials, etc. may be needed. We combine all this concepts under one notion – means. Under means we understand any artifact that was not manufactured during the given process, but that is needed for running this process. This notion is very general; for example it includes the process definition that should be followed when running each process instance of a given type.
To execute activities in the frame of the process we need people (staff) and means. In the situation when availability of a particular type of persons or artifacts (e.g., a tool), is limited in one way or another, we talk about resources, and resource assignment or resource allocation or resource distribution. Very often (but, not always) the limitation arises when one and the same person or artifact can be used in more than one process, or in more than one activity in the frame of the same process.
To distribute resources between several processes (process instances) or several activities of the same process, one or several resource managers may be required. A resource manager can coincide with the process supervisor, but this is not mandatory (matrix management). Normally resource manager serves more than one process instance and more than one process type. Again, having a resource manager does not mean that he is engaged in resource assignment for each activity in each process he is responsible for. The assignment can be done automatically in most cases. Anyway, a resource manager may be needed in case of conflicts to prioritize particular activities or processes.
Note that the resource manager does not need to be a middle- or high-level manager, this role may be played by a secretary, for example
All resources needed can be roughly divided into two groups: human resources, i.e., staff, and non-human resources, e.g., equipment, office room, etc. Human resources are most important for business processes. Distribution of human resources is normally tightly connected to the organizational structure of the owner. The structure may be very complicated. However, for the sake of resource distribution, we can considered a simplified structure as consisting of a number resource pools. Each pool includes several members of staff, and have one or several resource manager assigned to it. Each resource pool is mapped to a number of activities it can complete in each particular type of processes handled by a particular process owner.
The process can posses an internal structure of hierarchical type. Namely, a process can be considered as consisting of a number of sub-processes. A sub-process can be defined as a series of activities (including the case when there is only one activity in the series) that leads to achieving a well-defined sub-goal.
In section 2, we defined a goal as a process reaching an acceptable final state. The process’s state can be complexly structured, including many parameters (variables) and relations between them. A sub-goal can be define as a process’s state some part of which satisfies the given conditions, for example the north wall of the house being in place. A series of activities aimed at changing this part of the state structure constitutes a sub-process.
Two sub-process considered to be independent if the parts of the process’s state they are aimed to change do not intersect. For example, sub-processes aimed at building the north and the south walls of the house can be considered being independent. The independent sub-processes can run in parallel, providing that there are enough resources to exploit this possibility.
Two different processes (process instances) may have something in common, for example, they may share human resources, i.e. one and the same person executes activities in both of them. Other examples include the processes with common owner, the processes with common subject, etc.
Some of relations between different processes are more or less associative, like the ones listed above. Others are more meaningful, i.e. they express situations when one process cannot be started or finished without the other. An example of meaningful relations constitute two processes related via one process delivering some means (material) needed for successful continuation of another process. Two process having a meaningful relationship are called to be interlinked. Below we’ll try to list the most important types of linkage between different processes:
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Policy, Plan (long-term, short-term or operative), Exception, Calendar etc.
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... To be continued ...