Computer Software, Programming

1
Computer Software, Programming AI

• Managing Information Resources
• PUAD 680
• Week 9

2
Agenda

• Discussants
• Current events
• Alter chap. 9
• ASPs
• Elliott, Humanity 2.0
• Sector surveys Bruckner, Hushour

3
Software, Programming AI (Alter chap. 9)

• Historical perspective
• Special requests for clarification/discussion
• Types of software
• Strategic Importance of Programs and Data
• Process of programming
• Simple example of computer program
• Programming language evolution

4
Historical Perspective

• Traditional MIS Concerns
• Maintainability
• Security
• Product of careful, systematic development and
  documentation by centralized systems staff
• Mimicked architecture of centralized mainframe
  computing where computers were precious and
  scarce.
• Management of scarce resources through careful
  planning implementation by technical experts.

5
Historical Perspective (2)

• Evolution of architecture
• Minicomputers displaced/supplemented mainframes
  (1970s/1980s)
• PCs displaced minicomputers (1980s/1990s)
• Computing power becomes ubiquitous
• Tensions with traditional centralized software
  development model

6
Historical Perspective (3)

• Emergence of
• client/server architecture
• Enterprise Resource Planning (ERP) systems
• Web/Internet revolution
• Reemergence of centralized management model to
  support mission- enterprise-critical systems.

7
Historical Perspective (4)

• Website becomes strategic asset
• Costly to develop
• Maintainability becoming an issue, esp. in
  rapidly changing environment
• In house development
• Hard to hire and maintain skilled staff
• Contracting out
• Expensive contracts, difficult to control costs,
  ensure quality

8
Basic Computer System
Control
Processing
Input
Output
Storage
9
Storage vs. Memory

• File cabinet vs. desk top size
• Storage store programs/data between uses
• Memory store programs/data during
  execution/processing

10
Processing Steps

• Read/interpret input
• Load program into memory from storage
• Execute instructions of program
• Create outputs (print, monitor)
• Store results

11
Program Language Generations

• 1st Machine
• 2nd Assembly
• 3rd Higher level languages
• Fourth generation

12
Machine Language Instructions

• Two components (Box 9.1, p. 362)
• operation code specifies what is to be done
  (add, compare, read, etc.)
• operand(s) specify primary storage address(es)
  of data
• Example
• 37 / 202 add contents of location 202 to
  accumulator
• A (B-C) D (E F)

13
Machine Language
476
14
Machine Language
0
15
Machine Language
35
16
Machine Language
10
17
Machine Language
60
18
Machine Language
60
19
Machine Language
0
20
Machine Language
12
21
Machine Language
168
22
Machine Language
228
23
Machine Language
228
24
Assembly Language

• cle
• add B
• sub C
• mpy D
• sto T

• cle
• add E
• mpy F
• add T
• sto A

25
Strategic Importance ofPrograms and Data

• Mission critical data
• Content
• Prompt delivery
• Security
• Software development costs
• Labor inputs
• Establishment/documentation of procedures
• IS as part of product/service (e.g., EDGAR)

26
Application Service Providers
27
Next Week

• Alter 10, Networks Telecommunications
• Sawhney Parikh
• Case Technology in the Washington State Park
  System (A)
• Sector surveys