IS Theories & Practices Systems Architecture & Infrastructure IS 655: Supplementary Note 1 CSUN Information Systems

Modified Zachman Framework The Product 2

3 Modified Zachman Framework The Stakeholders

Modified Zachman Framework The Product Components 4

5 Modified Zachman Framework The Building Process

6 Modified Zachman Framework

7 Systems Development Process Scope Definition Phase: What Business Problem Problem Analysis Phase: What System Issues (Info/Data, Processes, Communications/Interfaces) Requirement Analysis Phase: What User Needs Logical Design: Conceptual Model – What to Do Decision Analysis Phase: What Solution Design Phase: Physical Model: How to Do Construction Phase: Do It Implementation Phase: Use It

1. Scope Definition Purpose: define perceived problems, opportunities, and directives (POD); assess the risk of project; establish scope, preliminary requirements and constraints, participants, budget and schedule (preliminary study) Issues: Is the project worthwhile? (using PIECES framework) Define the scope of project Deliverable: Project charter/plan Feasibility check: Cancel project / Approve to continue / Reduce or expanse the scope with budget and schedule modification 8

PIECES Framework for Systems Improvement P the need to improve performance I the need to improve information (and data) E the need to improve economics, control costs, or increase profits C the need to improve control or security E the need to improve efficiency of people and processes S the need to improve service to customers, suppliers, partners, employees, etc. 9

2. Problem Analysis Purpose: to study and analyze the existing system from the users’ perspectives as they see Data, Processes, and Interfaces Issue: Cost/benefits of building new system to solve these problems Deliverable: system improvement objectives (business criteria to evaluate the new system) Feasibility check: Cancel project / Approve to continue / Reduce or expanse the scope with budget and schedule modification 10

Problem Statement 11

3. Requirement Analysis Purpose: discover users’ needs or expectations out of the new system in terms of Data, Processes, and Interfaces Issue: Specify requirements for the new system (WHAT TO BE DONE) without prematurely expressing technical details (HOW) Errors and omissions in requirement analysis result in user dissatisfaction of final system and costly modifications Deliverable: business requirements statement 12

13 System Improvement Objectives

4. Logical Design Purpose: translating business user requirements into a system model that depicts only WHAT TO DO without specifying any possible technical design or implementation of those requirements (conceptual design). Issue: using graphical model of a system to represent user requirements in terms of Data, Processes and Interfaces, and to facilitate improved communication between system stakeholders. Caution: Analysis paralysis – excessive system modeling dramatically slows progress toward implementation of the intended system solution. Deliverable: Logical Systems Models (DFD, ERD etc) 14

15 SoundStage System Context

16 Soundstage Process Model

17 SoundStage Data Model

5. Decision Analysis Purpose: identify all candidate solutions, analyze the feasibility of each candidate, recommend a candidate system as the target solution Issue: Feasibility analysis in terms of technical, operational, economic, schedule (TOES), and risk Deliverable: approved system proposal Feasibility check: Cancel project / Approve system proposal with budget and schedule modification / Reduce the scope of proposed solution with budget and schedule modification

19 Candidate Systems Matrix

20 Candidate Systems Matrix…

21 Feasibility Matrix

22 Costs for Proposed Systems Solution

23 Net Present Value Analysis

24 Payback Analysis

25 Project Scheduling

Decision Analysis Candidate solutions evaluated in terms of TOES and Risks: –T echnical feasibility – Is the solution technically practical? Does our staff have the technical expertise to design and build this solution? –O perational feasibility – Will the solution fulfill the users’ requirements? To what degree? How will the solution change the users’ work environment? How do users feel about such a solution? –E conomic feasibility – Is the solution cost-effective? –S chedule feasibility – Can the solution be designed and implemented within an acceptable time? –Risk feasibility – What is the probability of a successful implementation using the technology and approach? (Risk Management)

6. Physical Design Purpose: to transform business requirements into technical design specifications for construction Issue: HOW technology will be used to build the system in terms of Data, Processes, and Interfaces Design by Specifications vs. Design by Prototyping Deliverable: System design specifications (blueprints) Feasibility check: Continue/ Reduce or expanse the scope with budget and schedule modification 27

7. Construction Phase Purpose: to build and test a system that fulfill business requirements and design specs; implement interfaces between new and existing systems Issue: Construct database, application programs, user/system interfaces, implement purchased or leased software Deliverable: proposed system within budget and schedule 28

8. Implementation Phase Purpose: deliver the production system into operation Issue: Train users, write manuals, load files, populate database, final test Conversion plan: parallel systems, switch point Deliverable: system up and running 29