Transcript Systems Modelling - Plymouth University

SDLC - Analysis
IDEF0 Modelling techniques
Why model processes?
Modelling provides:
consensus on the form of existing processes
consensus on what is to be changed
Modelling costs:
lots of time
lots of effort
Modelling technique
Dynamic technique to support the
capture of process knowledge
BPWin
computer based tool that encapsulates
particular syntax
rules and symbols used to create the model
Architecture of processes
Manage
Processes
Operate
Processes
Support
Processes
Set Direction
Formulate Strategies
Direct Business
Get Order
Develop Product
Fulfil Order
Support Product
Manage Finance
Support Personnel
Manage Technology
Corporate Learning
Operate processes
IDEF0 introduction
Background
Activities
ICOMs
Decomposition
Consistency
Node index
IDEF0 Rules
IDEF0 background
US military system analysis tool
Developed during the 1970’s
Part of Polaris programme
Used to model missile development
activities
Modified for business use
IDEF0, IDEF1.x, IDEF2, IDEF3
IDEF0 - activities
What is actually done in the system
Get order
order
Develop product design
Fulfil order
product
Support product
support
IDEF0 - ICOMs
Inputs - physical or informational
Output - physical or informational
Mechanism - enables activity to occur
Control - governs activity / transformation
IDEF - the box
Trigger /
Control (noun)
Input (noun)
Output (noun)
Activity
(verb)
A1
Mechanism (noun)
IDEF0 - Context diagram
C1
I1
O1
Activity
(verb)
A1
M1
A-0
IDEF0 - Top Level
C1
I1
A1
A2
A3
O1
A4
A0
M1
IDEF0 - Decomposition
A1
A2
A3
A4
A41
A42
A43
IDEF0 - Node Tree
A0 System Transformation
A1 High level process 1
A2 High level process 2
A21 sub process 1
A22 sub process 2
A23 sub process 2
A3 High level process 3
IDEF0 - Rules
Every box must have a control
One diagram per page, 3-6 boxes
Activities must be described by verbs
All arrows must be labelled, including
decomposed arrows
Arrows may join or divide
Arrows may be combined at higher levels
and decomposed at lower levels
IDEF0 - the process
What activities are being performed
What inputs are being transformed into
what outputs
What influences/controls/triggers/
regulates/constrains these activities
What means are required to perform
these activities