For the purposes of this body of work, we consider a resource to be an entity that is capable of doing work. This is usually assigned to the resource in the form of work items, each of which describe an integral unit of work that the resource should undertake. A resource is classified as either human or non-human i.e. a resource that does not correspond to an actual person - e.g. plant and equipment. A human resource is typically a member of an organisation. An organisation is a formal grouping of resources that undertake work items pertaining to a common set of business objectives. They usually have a specific position within that organisation and in general, most organisational characteristics that resources possess relate to the position(s) that they occupy rather than directly to the resource themselves.
As a consequence of their position(s), resources may have a number of associated privileges. They may also be a member of one or more organisational units which are permanent groups of human resources within the organisation that undertake work items relating to a common set of business objectives. Similarly they may also be a member of one or more organisational teams. These are similar to organisational units but not necessarily permanent in nature. Even less formal in nature is the notion of organisational groups which are often used to define groupings of resources with some common characteristic or cause e.g. social club members, fire-wardens etc.
Each resource is generally associated with a specific branch which defines a grouping of resources within the organisation at a specific physical location. Resources may also have a level which indicates their position within the organisational hierarchy. They may also belong to a division which defines a large scale grouping of resources within an organisation either along regional geographic or business purpose lines. In terms of the organisational hierarchy, each resource may have a number of specific relationships with other resources. Their direct report is the resource to whom they are responsible for their work. Generally this is a more senior resource at a higher organisational level. Similarly, a resource may also have a number of subordinates for whom they are responsible and to which each of them report.
Finally, a resource may also have a delegate which is an alternate human resource to which they assign work items previously allocated to them. This reassignment of work items may occur on a temporary or permanent basis. A resource may have one or more associated roles. Roles serve as another grouping mechanism for human resources with similar job roles or responsibility levels e.g. managers, union delegates etc. Individual resources may also possess capabilities or attributes that further clarify their suitability for various kinds of work items. These may include qualifications and skills as well as other job-related or personal attributes such as specific responsibilities held or previous work experience. They may also have features which further describe specific characteristics that they may possess that could be of interest when allocating work items.
Non-human resources may be durable or consumable in nature. A durable resource is one whose capacity to undertake work is unaffected by the amount of work that it has undertaken, whereas a consumable resource is one that is consumed (either partially or wholly) in the act of completing a work item. There is usually a rate of consumption or capacity associated with consumable resources indicating how much work they can actually undertake before being depleted and requiring further replenishment. Each resource may have a schedule and history associated with them. These are essentially inverses of each other.
A schedule is a list of work items that a resource is committed to undertaking at a specified future times where as a history or work log is a list of work items that a resource has completed (successfully or otherwise) at some time in the past.
Several commercial workflow systems have been examined in the context of this body of work. Most of these utilise an internal organisational model to identify resources and represent the relationships that exist between them.
- Staffware has a relatively simple model that denotes users (i.e. individual resources), groups and roles, and allows work to be assigned on the basis of these groupings. The use of roles is somewhat restrictive as each role can only be undertaken by a single user.
- WebSphere MQ Workflow provides a richer model that allows users to be described in a broader organisational context (e.g. organisational unit, branch, division to which they belong, who their manager is). It also supports roles and there can be a many - many correspondence between users and roles. Work items can be assigned to users based on various characteristics of the organisational model.
- FLOWer supports an organisational model that is exclusively role-based and is defined in terms of a role hierarchy. Correspondences are established between individual users or groups of users and roles. All work allocations are role-based.
- COSA provides an organisational model that embodies many of the human resource concepts. Users can be defined and organised into groups and hierarchies of groups are supported. Additionally both individual users and groups can be assigned roles and there is provision for the identification of group supervisors. Competencies can be identified for individual workflow users. Work items can be routed to users using any of these concepts.
- iPlanet has a minimal organisational model that allows for the identification of users and assignment of roles to users. There is also support for extended user profiles that allow attributes to be used in the allocation of work to users.