INFO 503Lecture #11 Introduction to Information Systems Analysis Foundations and Building Blocks INFO 503 Glenn Booker

INFO 503 Lecture #1 1

Introduction to InformationSystems Analysis

Foundations and Building Blocks

INFO 503

Glenn Booker


Syllabus

• This class focuses on understanding the ways in which the concept for a product can be turned into requirements and a design

• Best to reach me by e-mail; phone if urgent• Will cover most of textbook; will not cover

object-oriented methods since that’s a very different approach (see INFO 620)

• Yes, the text is quite repetitive


Syllabus

• All course materials are on my web sitehttp://users.snip.net/~gbooker/

• Be sure to read the General Course Information and Document Review Notes (http://users.snip.net/~gbooker/general.htm) and (http://users.snip.net/~gbooker/doc-review.doc)

http://users.snip.net/~gbooker/

http://users.snip.net/~gbooker/general.htm

http://users.snip.net/~gbooker/general.htm

http://users.snip.net/~gbooker/doc-review.doc


Why So Many Military Sources?

• They have vast experience with the development and acquisition of complex software and systems

• Which was paid for with tax dollars, so… • Many of their lessons learned are

freely available! – (Under References, look for SEI, INCOSE,

and STSC.)

http://www.sei.cmu.edu/publications/documents/doc.list/2002.htm

http://www.incose.org/

http://www.stsc.hill.af.mil/


My Biases

• DOD and FAA background, so I apologize for the TLA’s (Three Letter Acronyms) – Speak up if I use one you don’t know

• Use a Systems Engineering approach; information systems are a special case

• Mostly work with long-lived systems, so maintenance issues get extra attention


Soundstage Entertainment Club

• …is a case study which is followed throughout the textbook

• It will not generally be discussed in class• FAST = “Framework for the Application of

System Techniques,” (p. 80) is a term for the system analysis and design approach used by the text; it is a condensed version of a typical systems development method


Information Systems

• Information systems are systems which use computer, database and/or data processing technology to store and analyze data

• A systems analyst supports development and maintenance of some system

• Development consists of several types of activities, including analysis and design of the system


Information System Applications

• Information system applications include– Transaction processing systems (TPS) to

handle orders, payments, reservations, or other transactions

– Management and executive information systems (MIS & EIS) produce reports to help run the business

– Decision support systems (DSS) help make decisions or refine business rules


Stakeholders

• Stakeholders are the people who affect the development and creation of your system

• Note that a given person could fulfill many stakeholder roles, or they may be so far separated that they never meet!


Types of Stakeholders

• General types of stakeholders include:– System Owners– System Users– System Designers– System Builders– System Analysts

• Each of these may include many more specific roles


System Owners

• The System Owner (a.k.a. sponsor) provides the money for a system to be developed

• They generally make the final decisions about the scope and future of the system

• Often technically ill informed


System Users

• The System User (a.k.a. end user) is the person who actually uses the product or system on a day-to-day basis to do their job

• Users may be internal (within your organization) or external (outside)

• Include support & professional staff, managers, customers, suppliers, andremote users


System Users

• Often the User (client or customer) is the person who controls the detailed requirements for a system

• Warning: The text often assumes the System User knows a lot about the detailed data requirements - may or may not be true– If not, the System Designer must fill in


System Designers

• System designers are the people who design the system (duh!)

• Often includes many technical specialties, such as database administrators, network designers, web architects, graphic artists, security experts, and experts in your business environment (a.k.a. Subject Matter Experts)


System Builders

• System Builders are the people who create the system designed by the Designers

• Includes the most technically specific experts, such as application, systems, and database programmers, network and security administrators, and system integrators


System Analysts

• Main role is problem solving; to fix an existing system or create a new one

• Uses the system development life cycle to manage and control the solution of problems

• Helps bridge the gaps among the other stakeholders who affect creation of a system


System Development Life Cycle

• The System Development Life Cycle (SDLC) is a structured series of activities used to produce a system which is ready for operational or production use

• Development is followed by the support or maintenance phase, which is hopefully the longest phase of the system’s life



• Any development life cycle generally includes five major activities:– Initiation - to establish the scope of the

problem, and develop the strategy and goals for solving the problem

– Analysis - to determine the problem’s causes and effects, and determine what requirements are needed

p. 37 (p. 10) 6th and (4th) edition



– Design - the architecture and structure which the solution should have to solve the problem the best way

– Implementation - create the solution, using software tools, source code, hardware, etc.

– Support and Improvement - find and fix existing problems in the operational system, and add new features


Software Life Cycle

• The system development life cycle is similar to the classic Waterfall software development life cycle– Life cycle phases are: concept development,

requirements analysis, high and low level design, coding, testing, and implementation

• This course mostly covers requirements analysis, high- and low-level design


Sequential versus Iterative

• System development can be done in one pass through the life cycle (like the waterfall), or an iterative approach can be used

• An iterative life cycle defines requirements and high level design, then does design and implement many times, adding more and more to the system each time

p. 41 (n/a)


Information Systems Architecture

• Contains three goal-oriented perspectives– Knowledge improve the Data which is stored

or manipulated by the system– Processes improve how people use the system– Communications, which improve the

Interfaces with people or other systems, and the effects of Geography on data distribution


Information Systems Architecture

• These three goals are met by the Builders of the system with three technologies– Database technologies to manage the data– Software technologies to implement

the processes– Interface technologies to

support communications


Information Services

• Information services may be located in a centralized organization used throughout a company, or it may be decentralized to support unique needs of each group within an organization

• Services may be outsourced - obtained from a third party, or obtained from consultants for each project which needs them


Information Services

• In extreme cases, a software solution provider may be used to support a massive software implementation (e.g. Oracle, SAP, PeopleSoft, etc.)

• Online services may provide business-to-business (B2B) or business-to-consumer (B2C) sales, or may provide product marketing (advertising)


Business Process Redesign

• Business Process Redesign (BPR) is the deliberate examination of business activities (processes) to reduce costs and make sure every step adds value to the product, whenever possible

• Tends to produce radical changes in an organization


Continuous Process Improvement

• Focuses on making lots of small or incremental changes to business processes in order to keep improving quality, productivity, etc.

• Goal is to keep improving process maturity and product quality forever


Process Maturity Models

• Quality standards and goals are often embodied in process maturity standards, to guide organizations’ process improvement efforts

• The primary software standard is the Software Engineering Institute’s (SEI’s) Capability Maturity Model Integration (CMMI)

http://www.sei.cmu.edu/cmmi/


ISO 9000

• The ISO 9000 standards define a quality system which affects most aspects of a business

• Focused on manufacturing environment, but also applies to software development

• Need ISO 9000 certification for doing business with the European Union

http://www.iso.ch/iso/en/iso9000-14000/iso9000/iso9000index.html


Globalization

• The Internet has brought global markets even closer together

• This affects system requirements such as – Language translation– Character sets to express those languages– Currency exchange (got Euro?)– Environmental aspects such as time zones– Available labor markets


Technology Influences

• Other technology trends have influenced information systems recently– Placement of seemingly everything on a web

page (and the expectation that information system interfaces will be web-based)

– Emergence of e-commerce and e-business– Security and privacy concerns– Freedom through wireless networking


Refine Stakeholder Perspectives

• System Owners determine the scope of the system; including its purpose, vision, goals, objectives, costs, and benefits

• May be technologically illiterate• Generally think in terms of development

time and money (both development and maintenance costs), and how they are offset by the benefits of the system



• System Users help determine its requirements; they only care what it does, not how it can do so (as a system user, do you care how a light switch works?)

• Help define products and processes for data input, validation, storage, and reporting

• Concerned about system interface and ease of use



• System Designers determine how the system will meet the requirements, including the types of technology to be used, and its high and low level structure

• Tend to specialize their expertise: database, software engineering, system integration, networking, process improvement, etc.



• System Builders create the system by writing code, testing it, and delivering the finished product

• This type of activity is not covered by this course, and includes network design, programming, etc.

• Changes most quickly with technology


Building Blocks

• Now that the stakeholders have been defined, we look at their relationships to the building blocks of the system:– Knowledge (Data)– Process– Communications (Interface and Geography)

p. 64 (49)


Building Blocks

• The Geography aspect is downplayed in version 6 of the text

• Think of the Geography aspect as the effect of the physical scale of the system (e.g. time zones, internationalization) and networking among parts of a distributed system (how much data do I need to send from site A to site B every day?)


Knowledge Building Blocks

• The System Owners only care about data in the broadest form of information– Owners want to know the state of business

resources, such as money, inventory, sales, facilities, etc.

– Owners express their concerns in simple statements about their business model, such as “CUSTOMERS are in SALES REGIONS”



• System Users want to know how to use the system to perform routine functions, such as placing an order or generating an inventory report

• They may know a lot about the data requirements in terms of relationships, including how a legacy system was used and could be improved upon



• System Designers translate requirements into the files and tables which will be used to capture and manipulate them

• This is expressed as a database schema, which may be limited by the type of database tool used (Access, Oracle, DB2, etc.)



• System Builders write the gory details which make it all happen – in some sort of language (SQL, COBOL, Ada, C+-, Visual Basic, etc.)

• Primitive systems had to use flat file technology, such as ISAM or FileMaker Pro, similar to using a spreadsheet


Process Building Blocks

• System Owners are interested in business functions

• Most information systems are function-based, such as finance, personnel, sales, etc.

• Recent trends are to blend these systems into one really big system, like ERP (Enterprise Resource Planning)



• System Users care about their business processes from the most practical perspective: when I get an order over the phone, I click on the Enter Invoice button and fill in the customer information…

• These processes are defined in policies, processes, and procedures, which are often defined by higher levels of management



• System Designers take the business processes, and show how they will be implemented and automated

• This results in application schema, which shows how the entire system will work via flowcharts, state diagrams, and/or structure charts



• System Builders write applications which implement the processes

• Applications result from writing source code, compiling it to produce “object” files, and linking the object files to produce an executable application

• Prototyping may be used to generate a quick model of the desired application


Communications Building Blocks

• System Owners are concerned about large scale interfaces:– How does this system relate to other systems in

this organization?– How does the customer relate to this system?– How does it relate to external systems?– What are the system’s inputs and outputs?– Are there any legal or regulatory concerns?



• System Users are very concerned about the interface to themselves! (A.k.a. the human-computer interface or HCI)

• Use of a graphical user interface (GUI) is expected

• User interface should follow common standards for “look and feel”



• System Designers must bridge the gap between the user interfaces and the system-level interfaces

• They plan how the user will be able to navigate in the application

• And keep track of what’s currently possible through state transition diagrams (e.g. typing ‘f’ versus ‘Alt–f’)



• System Builders create the user interfaces, possibly using a graphical development tool like Visual Basic or PowerBuilder

• Middleware, such as ODBC (Open Database Connectivity), is often used for system-level interfaces, such as communicating between database programs


Geography Building Blocks

• System Owners often think in terms of operating locations– Where is it most effective to operate this

system? Labor rates, tax laws, and customs may affect the answer.

• How distributed will this system be?

• How will sites be affected by this system?



• System Users tend to know a lot about the system requirements for their location or organization

• Be sure to get input from all kinds of System Users!

• Communication requirements may come from geographic considerations



• System Designers need to define the network configuration (topology) which will best serve this system

• Also need to consider how the processing work is divided geographically, and how the inputs and outputs will get to those locations (kind of like traffic flow)



• System Builders implement the means for communication across the network

• May use various protocols to express information from each network (TCP/IP, IPX, etc.)

• May need to consider how the system responds when part of it is not available

Documents

INFO 503Lecture #11 Introduction to Information Systems Analysis Foundations and Building Blocks INFO 503 Glenn Booker