Embed Size (px)
Citation preview
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 1
CSCC40Analysis and Design of Information Systems
These lecture slides are provided for the personal use of students taking CSCC40 in the Fall term of 2007 at the University of Toronto. Copying for purposes other than this use, and all forms of distribution are expressly prohibited.
Some slides are adapted from the course textbook:Object-Oriented Systems Analysis and Design Using UML. 3rd ed. Bennett, McRobb, Farmer. McGraw-Hill. 2002.
The following sources of information are also recommended • Project Management Institute• Association of Computing Machinery• IEEE Computer Society
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 2
ACM computing curricula 2001software engineering
processesrequirements and specificationsdesignvalidationdelivery of systemsevolutionproject managementtools and environmentscomponent-based computingformal methodsreliability
these topics are covered in CSCC40 and CSCD08
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 3
inboundlogistics:
raw materialshandling,inventory
service:installation,
repairs, parts
sales andmarketing:advertising,promotion,
pricing
outboundlogistics:
ware housing,distribution
operations:machining,assembly,
testing
primaryactivities
procurementpurchasing raw materials, machines, supplies
firm infrastructuregeneral management, accounting, finance, strategic planning
human resources managementrecruiting, training, development
technology developmentR&D, product and process improvement
supportactivities
value chain
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 4
business strategy
information systems strategy
information technology strategy
what must be done
system requirements
where IT can help
informsand
enables
drivesandsets
goals
hardware capabilities
Fig. 1.10 the relationship between business, IS and IT strategies
missions, strategies and their realization
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 5
what the system does
how the systemis controlled
inputs outputs
controlfeed-forward feedback
system boundary
all systems (manual and/or automated) have these characteristics
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 6
onlineand/or batch
distributedand/or centralized
corporateand/or departmentaland/or public
types of systems
transaction processing systems
management information systems
decision support systems
expert systems
real-time (control) systems
other
each can be implemented as
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 7
the three perspectives
technologicalhardware, networks, databases, CASE tools ...
socialhow do individuals and organizations use information, how are they affected by technology…
professionalpractices and standards, policies, quality practices ...
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 8
hardware software
communication
personal computers,workstations, mainframes,hardware components,CPUs, memory, disks,peripheralspalmtops ...
word processing,spreadsheets,presentation software,website design,web search engines,document managementCASE tools ...
e-mail, fax,wireless communication,telephone,networks, internet ...
technologies foranalysis and design
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 9
fun
ctio
nal
dec
om
po
siti
on
o
f b
usi
nes
s
Ho
ffe
r, G
eo
rge
, V
ala
cic
h.
Mo
de
rn S
ys
tem
s A
na
lys
is a
nd
De
sig
n.
2nd e
d.
Ad
dis
on
We
lse
y 1
99
9.
business function
supporting function
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 10
typical suite of systems
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 11
decomposition of a business system
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 12
Where does one system end, and another start?
If a system is a subjective view of reality, then who’s view do we work with?
How do we cope when:
• the system is too large to be understood by any one person?• technology is changing all the time?• user requirements are changing all the time?• new development tools and techniques and methodologies are constantly needed?
conceptual complexity !
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 13
we have coping strategies !
methodologies: waterfall, prototype, extreme . . .
time-tested techniques for: verification, validation, estimating . . .
abstraction and decomposition
modeling methods: structured, object-oriented . . .
tools for: project control, design control, configuration management . . .
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 14
from end user’s perspective ...What system? I haven’t seen a new system. (vaporware)It might work, but it’s dreadful to use. (lots of reasons)It’s pretty, but does it do anything useful? (not an improvement)
from client’s perspective ...If I’d known the real price, I’d never have agreed.It’s no use delivering it now –we needed it last April.OK, so it works, but the installation was such a mess, my staff will never trust it.I didn’t want it in the first place.Everything’s changed now –we need a completely different system.
what we want to avoid / prevent ...
University of Toronto at Scarborough © Kersti Wain-Bantin CSCC40 course intro 15
from the developer’s perspective ...We built what they said they wanted.There wasn’t enough time to do it any better.Don’t blame me –I’ve never done O-O analysis before.How can I fix it –I don’t know how it’s supposed to work.We said it was impossible, but no-one listened.The system’s fine –the users are the problem.
what we want to avoid / prevent ...
