System Design and Specification

• Assignment 1 must be submitted before Sunday, March 30, 2025
• Class Test 5 focusing on Chapter 6 will be available from Friday, March 28 to Friday, April 4
• The Chapter 7 Class Activity will be available from Friday, March 28

Chapter 7

• Chapter focuses on moving from Systems Analysis to System Design
• Initial transition from analysis to design is explained
• System specification is created
• Discussed are Custom, Packaged, and Outsourced alternatives for acquiring a system.
• An alternative matrix is created

Transition from Requirements to Design

• In Systems Analysis, business needs are identified
• In System Design, strategies to fulfill those needs are identified
• The "logical" work from Systems Analysis is converted to the "physical" in System Design
• Design phase involves deciding how to build the system
• System requirements are created and should describe all technical details for building the system
• System specification is the final deliverable from design phase
• System specification conveys what system the development team will implement during the implementation phase
• Analysis and design phases are interrelated

Elements of System Specification

• Recommended System Acquisition Strategy
• System Acquisition Weighted Alternative Matrix
• Architecture Design
• Hardware and Software Specification
• Interface Design
• Physical Process Model
• Program Design Specifications
• Physical Data Model
• Data Storage Design
• Updated CRUD Matrix
• Updated CASE Repository Entries

System Acquisition Strategies

• Focus is on finding the best way to acquire a system

Ways to Acquire a New System

• Custom Development, system is built from scratch in-house
• Purchase a software package and customize it, install software on your own computers or obtain access from a software provider
• Outsource development to a third party, the third party builds the system from scratch or purchases software

Custom Development

• Pros: get exactly what is desired, new system is built consistently with existing technology and standards
• More pros include building and retaining technical skills and function knowledge in-house, team flexibility and creativity, and unique solutions are created for strategic advantage
• Cons: requires significant time and effort, may add to existing backlogs, and may require skills not already present
• Other cons include it often costing more, often taking more calendar time, and risk of project failure

Purchased Software

• Application Service Providers (ASP) supply access to software on a pay-as-you-go basis
• Many applications today are "in the cloud"
  • ASP hosts someone else’s software
  • SaaS is a software vendor who hosts its own software
• Considerable savings occur, with no hosting infrastructure needed, as the host provides everything
• Risks with purchased software include fear of losing confidential information and performance issues
• Analyze the vendor and the software functionality
• Verify vendor claims with others and look carefully at vendor support
• Assess long-term viability of vendor as an on-going business, consider if a new software company can survive as a business over the long haul
• Consider what happen to a software product if the vendor is an acquisition target

Purchased Software Packages

• Packages are purchased or obtained from an ASP or SaaS
• Pros: no need to "reinvent the wheel" for common business needs, tested, proven product, cost savings, time savings, utilize vendors' expertise, and some customization may be possible
• Cons: rarely a perfect fit, organizational processes must adapt to software
• Other cons include reliance on vendor for maintenance and future enhancements, no development of in-house functional and technical skills, unique needs may go unmet, and system integration may be required

Systems Integration

• Building systems combines packages, existing (legacy) systems, and custom software written for integration
• Integrating data between various parts of the system is the key challenge. -May require data transformations
• Many consultants specialize in systems integration

Outsourced Development

• Pros: hire expertise that is not already present, may save time and money, and lower risk
• Cons: no opportunity to build in-house expertise, reliance on vendor, and future options limited
• More cons include security and potential loss of confidential information and performance based on contract terms

Outsourcing

• Involves hiring an external vendor, developer, or service provider to supply the system.
• Can also obtain custom system created by outsourcer
• Can reduce costs and/or add value like resources or experience
• Risks include losing confidential information, control over future development, and learning opportunities

Outsourcing Contracts

• Three primary types exist: time and arrangements, fixed-price, and value-added

Outsourcing Guidelines

• Keep lines of communication open
• Define and stabilize requirements before signing the contract
• View the relationship as a partnership
• Select vendor, developer, or provider carefully
• Assign someone to manage the relationship
• Don’t outsource what is not understood
• Emphasize flexible requirements, long-term relationships, and short-term contracts

Acquisition Strategy Selection Factors

• To use custom development the business need must be unique, in-house functional and technical experience must exist, and desire exists to build in-house skills
• A highly skilled project manager and a proven methodology must be present and the time frame must be flexible
• To use a packaged system the business need should be common, in-house functional experience must exist, and the skills needed are not strategic
• Project should have a skilled project manager who can coordinate vendor’s efforts, the time frame should be short
• To use outsourcing, the business need is not core to the business and in-house functional or technical experience does not exist
• Decision must be a strategic one, project has a skilled project manager who matches the scope of the outsourcing deal, and the time frame should be short or flexible

Developing Our Options

• Gathering information needed before starting, includes tools and technologies needed for custom development
• Should identify vendors who make products that address the needs and service providers who could build outsourced applications

Request for Proposals (RFP)

• Solicits proposals from vendors, developers, or service providers
• Explains the system to be built and criteria for selecting applicants
• Request for Information (RFI) is a shorter and less detailed version
• Request for Quote (RFQ) is for when you just need a price

Typical RFP Contents

• Description of desired system
• Special technical needs or circumstances
• Evaluation criteria
• Instructions on how to respond
• Desired schedule
• Other information that will help the submitter to make a more complete or accurate proposal

Developing an Alternative Matrix

• Combine several feasibility analyses into one matrix
• Include technical, economic, and organizational feasibilities
• Assign weights to indicate the relative importance of the criteria
• Assign scores to indicate how well the alternative meets the criteria