CPS 213 Study Guide - Summer 2018, Comprehensive Midterm Notes - Interaction, Systems Analysis, Source Code
12 Oct 2018
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Department
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CPS 213
MIDTERM EXAM
STUDY GUIDE
Fall 2018
♠ CPS 731 NOTES – WEEK 1
♠ Project 30%
♠ Midterm 30% - October 27th
♠ Final 40%
♣ What is a System
♦ System: collection of related programs or applications
♦ These programs work together in an organized way
♦ They communicate through files, databases, and networks
♦ Systems can also have:
• Non-computerized components (ex. people or other types of machines)
• Processes that are performed outside of a computer system
♦ Systems analysis and design involves:
• Determining the system requirements
• Designing the system and its components
• Managing its implementation
• Managing its deployment
♣ The Origins of System Analysis
♦ Started in the manufacturing sector
♦ Need to find most efficient way to produce a product (involved both people and machines)
♦ Systems analysis can trace its roots back at least one hundred years to the assembly line
♦ Moved into the office environment ~1930s - used to automate office processes
♦ Early systems analysts were often called efficiency experts - spent a lot of time measuring time to perform
simple operations
♦ Primary goal of early systems analysis:
• Converting manual processes to computer
• Computerization of information based systems
♦ Before converting a manual system to a computer based system, the existing system was analyzed
♦ Early systems analysis converted systems one at a time
♦ Resulted in two key problems:
1. Change wasn't considered - the systems were static
2. No communications between systems - each system was developed in isolation
♣ Problem 1: Change Wasn't Considered
♦ System Analysis (1930s-1950s)
♦ business processes were very static often stayed the same for decades
♦ business schools taught the standard ways of doing common processes
♦ often a long time was required to design and implement a new system
♦ System Analysis (1960s)
♦ Government started becoming more active, introduced policies that had an impact on business processes
♦ Global competition increased the speed of business - required businesses to react quicker and be more
innovative
♦ These changes first impacted manufacturing, but soon effected all business processes
♦ Systems could no longer be static, had to respond to these changes
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♦ Problem: Systems needed to be changed, but weren't designed for change. Resulted in large, complicated
systems (legacy systems)
♣ Problem 2: No Communications Between Systems
♦ Early systems did not communicate - companies had a small number of computers (often only 1) which could
run one or two programs at a time, really no ability to communicate
♦ Only communication was with files, this was static and was minimized
♦ Limited ability to combine information
♦ As businesses evolved their needs for information changed
♦ This information was spread over multiple systems that didn't talk to each other
♦ Needed to combine information in new ways and be more flexible
♦ Stored information in multiple systems, more than once, different in each system
♣ Legacy Systems
♦ One of the biggest challenges in businesses today is maintaining these systems
♦ Systems can be over 40 years old, programs have evolved over 40 years
♦ Are often very complicated and hard to understand
♦ Tend to be the most important systems so replacement is very risky - companies cannot function without them
♦ Programs are written in old programming languages: COBOL, System 360 assembler, RPG, etc.
♦ Produced for computers that no longer exist - were obsolete decades ago
♦ Need to keep these programs running, modify them, integrate them with new systems
♦ In many cases programs can be migrated to newer hardware
♦ However, some cannot - ex. current IBM mainframes still support IBM 360 software
♦ Software emulators exist for old computers
♦ Some hardware companies specialize in obsolete architectures
♣ The Database Revolution
♦ System Analysis (1980s)
♦ Early databases were system specific, but relational databases opened the possibility of enterprise wide data
storage
♦ The vision: a company would have a single database that all systems shared
♦ With one copy of each piece of information, systems could easily communicate, extract information, etc.
♦ The Reality: most companies have multiple databases
• Legacy applications need to be converted to use common database
• Systems often viewed the same data differently, due to conversion
• Developers/managers didn't want to change
• Database systems weren't powerful and flexible enough to handle large applications
• The vision has not worked completely
♣ Networking Systems
♦ Systems Analysis (1990s)
♦ Networking was everywhere
♦ Over the past decade time has changed drastically for businesses:
• Transactions that could take 1-2 days must now be done in seconds
• Must be open 24/7, process transactions at any time, not only once a day, must always be available
♣ Today's Systems
♦ Problems and Challenges
♦ Customers now interface with systems, must be easy to use
♦ Systems need to be reliable
♦ System integration - need systems that integrate across companies
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
System: collection of related programs or applications. These programs work together in an organized way. They communicate through files, databases, and networks. Systems can also have: non-computerized components (ex. people or other types of machines, processes that are performed outside of a computer system. Systems analysis and design involves: determining the system requirements, designing the system and its components, managing its implementation, managing its deployment. Need to find most efficient way to produce a product (involved both people and machines) Systems analysis can trace its roots back at least one hundred years to the assembly line. Moved into the office environment ~1930s - used to automate office processes. Early systems analysts were often called efficiency experts - spent a lot of time measuring time to perform simple operations. Primary goal of early systems analysis: converting manual processes to computer, computerization of information based systems. Before converting a manual system to a computer based system, the existing system was analyzed.
