INFO425: Systems Design INFORMATION X Finalizing Scope (functions/level of automation)  Finalizing scope in terms of functions and level of automation for each function overlaps with and requires information from:  Defining target deployment environment  Defining implementation alternatives >e.g., build vs. buy  General Approach for including/excluding functions:  Functions deemed mandatory are in scope.  Include as many important functions as budget and schedule allow  Desirable features: delay to later ‘release’ of system  Strategic plan:  Often, genesis of a new system is organization’s strategic plan  Functions that align with strategic plan typically get included in scope

INFO425: Systems Design INFORMATION X Finalizing Scope (functions/level of automation)  Need to revisit feasibility analysis. Now have much more information to work with.  Economic feasibility  What set of functions give us an optimal return on investment?  What set of functions can we afford?  Schedule and resource feasibility  What can be implemented in time available?  What can be implemented given human and other resources?  Technological feasibility  What can be practically implemented given state of technology and organizations knowledge and experience?  Operational, organizational, and cultural feasibility  What can our organization handle/accept?  How much change is required?

INFO425: Systems Design INFORMATION X Application Deployment Environment  What is the technical environment in which system will be implemented?  Deployment environment consists primarily of:  Hardware  Networks  System software  Development software  Development methodology and tools  Technical requirements define constraints regarding deployment environment  Organization’s current environment/standards typically drive deployment options

INFO425: Systems Design INFORMATION X Range of Application Types  Stand-alone applications on mini- and personal computers  Online interactive applications  Distributed applications  Web-based applications

INFO425: Systems Design INFORMATION X Hardware, System Software, and Networks  Computers range from handheld to super computers  Operating systems range from Windows to Unix  Database management systems range from Oracle to SQL Server to IBM DB2  Software components and standards range from Java 2 Enterprise (J2EE) to Microsoft.NET  Web servers range from IIS to Apache

INFO425: Systems Design INFORMATION X Deployment Environment Characteristics to Consider  Compatibility with technical requirements:  Volume of transactions, location of users, etc.  Compatibility among hardware and system software  Required interfaces to external systems  Conformity with IT strategic plan and architecture plans  Cost and schedule

INFO425: Systems Design INFORMATION X Development Tools  Development environment – programming languages, CASE tools, and other software used to develop application software  Java and Visual Studio.NET are examples  Application deployment environment decisions limit development tool choices  Operating system environment  Database management system (DBMS)  Distributed software standard

INFO425: Systems Design INFORMATION X Development and System Software Environments  Consists of standards and tools used in an organization to develop systems  Important considerations  Language environment and expertise >Java, C, etc,  Existing CASE tools and methodologies >RUP and Rose, Information Engineering  Required interfaces to other systems  Operating system environment >Unix, Linux, OS390, NT  Database management system environment >Oracle, DB2, SQL Server

INFO425: Systems Design INFORMATION X Choosing Implementation Alternatives  Many variations on obtaining a system  Facilities management solutions  Packaged, turnkey, ERP software systems  Custom software development  In-house development

INFO425: Systems Design INFORMATION X Implementation Alternatives ASPs Salesforce. com MySAP.com ERPSAPPeopleSoft Off the shelf packages Simply Accounting We build, consultants build or blended approach

INFO425: Systems Design INFORMATION X Identifying Criteria for Selection  Comparisons difficult  Different proposed systems have strengths in different areas  Need a consistent framework for comparison of alternatives  Criteria  Weights  Scores  Three areas to consider  General requirements  Functional requirements  Technical requirements

INFO425: Systems Design INFORMATION X Evaluation Framework Evaluation Criteria Weight – importance of criteria vs other criteria Alternatives considered Score Score * Weight Total49Total42

INFO425: Systems Design INFORMATION X EVALUATION FRAMEWORK (EXPANDED)

INFO425: Systems Design INFORMATION X General Requirements  General requirements include considerations that are important but not directly associated with the computer system itself.  Related to feasibility assessment – alternative must be feasible to be chosen  General requirements examples:  Performance record of the provider  Level of technical support from the provider  Warranties and support services (from outside vendor)  Availability of experienced staff  Development cost  Expected value of benefits  Length of time (schedule) until deployment  Requirements for internal expertise  Organizational impacts (retraining, skill levels)

INFO425: Systems Design INFORMATION X Technical Requirements  Constraints under which system must operate  Defined by technical requirements identified during information gathering  Categories:  Performance (response time/throughput, etc)  Security and Control  User interface (ease of use, etc.)  Service (number/location of users to be supported)  Operating environment  etc.

INFO425: Systems Design INFORMATION X Functional Requirements  Need to evaluate alternatives based on how well they meet functional requirements.  Use expanded event table

INFO425: Systems Design INFORMATION X Evaluating Functional Requirements

INFO425: Systems Design INFORMATION X Evaluating Technical Requirements

INFO425: Systems Design INFORMATION X Making the Selection uAfter rating alternatives, choice can be made uScores are tabulated and compared

INFO425: Systems Design INFORMATION X Partial Matrix of General Requirements Systems Analysis and Design in a Changing World, 5th Edition 20 Figure 8-7

INFO425: Systems Design INFORMATION X Partial Matrix of Functional Requirements Systems Analysis and Design in a Changing World, 5th Edition 21 Figure 8-8

INFO425: Systems Design INFORMATION X Partial Matrix of Technical Requirements ‏ Systems Analysis and Design in a Changing World, 5th Edition 22 Figure 8-9

INFO425: Systems Design INFORMATION X Contracting with Vendors  Generate a Request for Proposal

INFO425: Systems Design INFORMATION X Presenting Results and Making Decisions  Compile, organize, and present the alternatives and critical issues in an easy-to-understand but complete manner  Final choice generally made by executive steering committee  Format of documentation and presentation style varies with organization