example =
music CD store
on the web
context diagram
shows system and all
external entity interfaces
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CSCC40 DFD examples
1
customer's
involvement
selection by
customer
order wrapup
1.1.1
display main
screen
1.1.2
find cd
1.1.3
display cd
1.1.4
add to order
1.1.5
display total
order
1.2.1
contact bank
1.2.3
process bank
reply
accept order
1.2.5 customer reset
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access site
enter search
parameters
view
information
about the cd
decide how
many to buy
check order,
then accept or
refuse (exit)
accept payment
key in name,
info
credit card, etc.
1.2.2
1.2.4
bank's
involvement
© Kersti Wain-Bantin
see error
message if
credit no good
see all info,
then make final
"accept"
decision
deliberately
"exit" or just
time out
receive credit
card info
send either
reject or
authorization
number
CSCC40 DFD examples
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part of the
hierarchy diagram
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CSCC40 DFD examples
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manager
involvement
staff
involvement
file
2.1.1
maintenance
add cd
description
accept or reject
cd's
2.1.2
update cd
description
add prices
2.1.3
receive
shipment
compare cd's
received to P.O
then update
inventory
2.1.4
change
inventory
count inventory
and correct
inventory if
necessary
send
2.2.1 confirmation
mail
purchasing
A/R system
system
involvement
involvement
provide soft
copy of cd info
provide P.O.
(purchase
order) info
update
discounts and
sales blurb
maintain
2.1.5
marketing blurb
reports and
interfaces
vendor
involvement
review orders
and approve
e-
2.2.2
today's
shipment report
look at what to
ship today
2.2.3
confirm today's
shipping
confirm what is
actually shipped
2.2.4
inventory
balances
2.2.5
sales reports
decide what to
order, what to
discontinue
compare cost to
revenue
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received
shipped info
create P.O.
CSCC40 DFD examples
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another part of the
hierarchy diagram
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CSCC40 DFD examples
5
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© Kersti Wain-Bantin
CSCC40 DFD examples
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final
hierarchy diagram
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© Kersti Wain-Bantin
CSCC40 DFD examples
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selection by
customer
Create
Read
Update
Delete
cd buy list
customer
information
display main
screen
1.1.2
find cd
R
1.1.3
display cd
R
1.1.4
add to order
R
C
R
R
display total
order
accept payment
1.2.1
info
R
R
C
1.2.2
contact bank
R
1.2.3
process bank
reply
U
1.2.4
accept order
U
1.2.5 customer reset
University of Toronto at Scarborough
marketing
blurb
1.1.1
1.1.5
order wrapup
cd
inventory
cd
description
note.
customer information
+ cd buy list = shopping cart
© Kersti Wain-Bantin
D
D
CSCC40 DFD examples
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2.1.2
2.1.3
Create
Read
Update
Delete
2.1.4
reports and
interfaces
add cd
description
update cd
description
receive
shipment
change
inventory
2.1.5
maintain
marketing blurb
2.2.1
send
confirmation
e-mail
2.2.2
U
U
U
C/R
U
U
U
today's
shipment report
R
R
confirm today's
shipping
inventory
2.2.4
balances
U
U
R
R
2.2.3
2.2.5
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cd buy list
C
customer
information
C
marketing
blurb
cd
inventory
file
2.1.1
maintenance
cd
description
note.
customer information
+ cd buy list = shopping cart
sales reports
© Kersti Wain-Bantin
R
R
R
R
CSCC40 DFD examples
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in tutorial you will
discuss these
entities
we may also need
some information
about these !!
we are carrying
information
about these
probably don’t
need info about
these
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CSCC40 DFD examples
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level 3 DFD
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CSCC40 DFD examples
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level 3 DFD
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CSCC40 DFD examples
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level 3 DFD
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© Kersti Wain-Bantin
CSCC40 DFD examples
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level 3 DFD
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CSCC40 DFD examples
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level 2 DFD
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CSCC40 DFD examples
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CSCC40 DFD examples
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real-time extensions
Current
gauge
Line
status
Line
tension
Report
line
status
Enable
Control
line
conditions
Disable
3.2
Enable
Disable
3.1
Tension off
Tension ok
Enable
Disable
Line
tension
material
inlet
3.3
Enable
Disable
KEY
name
ID
Control flow
(discrete)
Inlet
control
Current
tension
Controlling
tension
Monitor
Tension
3.4
3.5
Tension settings table
Control
Transformation
Control flow
(continuous)
name
Control
Store
Tension
inlet control
Source: Svoboda, C. P. “Structured Analysis”. In Thayer, R. H and Dorfman, M. (eds.) “Software Requirements Engineering, Second
Edition”. IEEE Computer Society Press, 1997, p255-274
© Steve Easterbrook
University of Toronto at Scarborough
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CSCC40 DFD examples
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