This document discusses role activity diagrams (RAD) which are used to model roles and activities in business processes. It defines roles as sets of responsibilities carried out through various activities. Examples of roles given include authoring, editing for publishers and programming, quality assuring for software development. Activities are what individuals do within their roles. The document outlines RAD notations for showing interactions between roles, indicating the driving role, and modeling alternative flows and concurrent activities using case and part refinement notations.

1. Dr. Awais Majeed
awais.majeed@bcs.org
Business Process Analysis
Role Activity Diagram (RAD)

2. Roles and activities
 A Role involves a set of activities which, taken
together, carry out a particular set of responsibilities.
 For a publisher possible roles are authoring, copy
editing, designing, editing, planning, producing, and
marketing.
 Software development roles can be project
managing, configuration controlling, programming,
quality assuring and designing.

3. Roles and activities
 Roles can take many forms
 A unique functional group e.g., Documentation
department, accounts
 A unique functional position or post e.g., head of
analysis department, managing director
 A rank or a job title e.g., senior engineer
 A class of person, e.g., trade union member,
customer
 An abstraction e.g., Progress chasing

4. Roles and activities
 Activities are what actors do as “individuals” in their
roles.
 While developing new pharm. drugs activities might
include prepare potential drug compound, carry out
clinical trial, prepare submission to regulatory
authority and check drug stability.

5. RAD Notations

8. Showing Interactions
 An interaction between roles is shown by a
white box in one role connected with a line to
a white box in another role
 An interaction can involve any number of
roles
 No arrows to define the flow of interaction
 Place annotation at the appropriate end
 The project manager role receives an estimate from the
Design role
 Indicated by an annotation ‘obtain estimate’ placed at the
project managers role end of the interaction line

9. Showing Interactions ..
 In some situations it is useful to show the
party who is going to lead an interaction
 This can be presented by shading the
interaction box of the driving role

10. Case Refinement
 During process execution, the next
state/activity might depend on the current
state or a condition
 Such alternative course of actions are
represented by the notation of case
refinement
 We refine the state of the process according
to different predicates or “cases”

11. Case Refinement ..
The 2-way case refinement can be generalised to an
N-way case refinements

12. Case Refinement ..
a) Iteration of activities
b) Returning to a main
thread of activity

13. Case Refinement ..
Alternative way of working …

14. Part Refinement – Concurrent activities
 A role can start a no of concurrent threads of
activities
 This can be shown with the RAD notation of
part refinement

15. Part Refinement – Concurrent activities
 If all concurrent activities have to be finished before resuming
to normal flow of activities we merge these threads as shown
below:
Parallel threads merging together Parallel threads with different paths of