System analysis module 2
information-gathering techniques- interviewing users and other stakeholders
-prepare detail questions - meet with individuals or group of users - obtain and discuss answers to the questions -document the answer - follow up as needed in future meeting or interviews Questions: What is the business process? How is the business process performed? What information is required?
Develop User- Interface dialogue? Explain
Main goal: Method of figuring out how to solve the uncertainty of many aspects of new system requirements that is about to replace the old system. This is a powerful method of eliciting and documenting requirements when the new system replacing the old system that does similar work user validation of a user interface is simpler and reliable because the user can see and fe the system analysts develop interface via: abstract models, interaction diagram and written dialogues, user storyboards or user interface prototypes on the actual input/output device that users will user (e.g. phone)
What is technology archietecture
a set of computering hardware ,network hardware and technology and system software employed by an organisation
What is system requirement?
all activities that a new system must perform or support and the constraints that the new system must meet
Important point about requirements?
be identified and precisely started early in development process and that inconsistence or trade- offs among them be resolved
Explain the Unified Modeling language is important to use as a standard for creating information systems models?
a standard set of information system model construct and notation define bu the oBJECT Management group
Physical requirements?
characteristics of hardware as size, weight, power consumption and operating condition
Implementation requirements?
constraints such as required programming languages and tools, documentation method and level of detail, and specific communication protocol for distributed components
Design constraints?
describe restriction to which the hardware and the soft ware must adhere. eg how much memory storage would an cellphone application take
Interface requirement?
describe the interactions among system Eg finance reporting system >>> Securities and exchange Commission (SEC)
Activity Diagram?
describes user (or system) activities, the person who does each activity, and the sequential flow of these activities Useful for showing a graphical model of a workflow - A UML diagram
What is the difference between functional requirement and non functional requirements?
functional requirements : - are the activities that the system must perform - based on the procedure and rules that an organization uses to run its business -use case details must be capture and modeled too Nonfunctional requirements: characteristics of the system other than those activities it must perform or support - URP- to find out == usability ** describe operational characteristics related to users, such as the user interface, related work procedure, online help, and documentation == reliability **dependability of a system e.eg service outage, incorrect processing, how it detects and recovers from those problems ===performance **describes operational characteristics related to measuring of workload; throughput and response time === security **how access to the application will be controlled and how data will be protected during storage and transmission
supportability requirements?
how a system for a game installed, configured, monitored and updated
What are 3 types of models?
textual model - text - based system models such as memos report narrative and lists Graphical models- system models that is pictures and other graphical elements to create a diagram mathematical models- system models that describes requirements numerically or as mathematical expression
Evaluating Requirements for users?
this sections focuses on eliciting users input to model requirements, return to the users for additional input or validation -incorporate the new input and refine the model - prototypes of user interface and other parts are developed and user = this allows to visualise innovative technologys
Technology Architecture
— the set of computing hardware, network hardware and topology, and system software employed by the organization
Application Architecture
—the information systems that supports the organization (information systems, subsystems, and supporting technology)
Reasons for Modeling
•Learning from the modeling process •Reducing complexity by abstraction •Remembering all the details •Communicating with other development team members •Communicating with a variety of users and stakeholders •Documenting what was done for future maintenance/enhancement
unstrctured questions are good for?
•Unstructured questions allows interviewer to pick up on issues, themes and vocabulary. They have rich detail but difficult to control or schedule and require good listening skills
What is a model?
a representation of some aspect of the system
Define Requirement ? Explain?
- specification of what should be implemented - uses information gathers from users + documents to define requirements = meaning the functions of the system ( what it should perform/how it should perform) = can make case diagram, activity diagram, and domain model class diagram -it must be unambiguous, testable, correct and complete 2 types: Functional requirements: - functions the system must perform Nonfunctional requirements: - issues as user-interface formats and requirements for reliability, performance, and security Main Goal: Use gathered info to make a model to: - records requirements, review the model with users, refine and expand the models to reflect new or updated info
Gather detail information? explain
-talk to people who will be using the system/ used a similar system -watch them work - read materials about the existing system -obtain additional info by reviews plan documents and policy statements study the existing system ( documentation) look at other companies that had to tackle similar situations Main Goal : identify + understand activities of all current and future users. How? look at the present and the future location where work occurs and all system interfaces with other systems
What are the benefits of doing vendor research during information-gathering activities?/
1) researching exisiting solution will frequently help users generate new ideas for how to better perform their business functionsE.g problem and how they solved 2) companies need the best solution so reach is important to make a system that solve basic business problem but that are update to date with competitive practices. 3) often cheaper and less risky to buy a solution rather than to build it. safer quicker, less expensive route. One danger in exploring existing solutions: The users and even the systems analysts may want to buy one of the alternatives immediately and later find only a fraction of the functions that were needed from the purchased packaged software system.
List and briefly describe the 6 information-gathering techniques
1)interviewing users and other stakeholders 2) Distributing and collection questionnaires 3) Reviewing input, outputs, and documentation 4) observing and documenting the business procedure 5)reaching vendor solution 6) Collecting activities user comments and suggestions
Describe the steps in preparing for, conduction, and following up on an interview session
1.Prepare detailed questions 2.Meet with individuals or groups of users 3.Obtain and discuss answers to the questions 4.Document the answers 5.Follow up as needed in future meetings or interviews
Why 'Unified'?
Development Lifecycle - UML provides a visual syntax for modelling all aspects and stages of the software development life cycle • Application Domains - UML has been used to model everything from real-time embedded systems to management decision support systems and everything in-between • Implementation Languages and Platforms - UML is language and platform-neutral. Works well for both OO languages (eg, Java, C#) and hybrids (eg, C++) - Many high-level diagrams - not language/platform related • Development Processes - Although UP and its variants are probably the preferred development process of OO systems, UML can (and does) support many other software engineering processes • Its Own Internal Concepts - UML valiantly tries to be consistent and uniform in its application of a small set of internal concepts. It does not always succeed, but it is still a big improvement on prior attempts
Prepare for an interview:
Establish objectives: •What do you need to find out? •What areas or aspects are important? •Do you need facts or opinions? •Do you need history? •Do you need to know how decisions are taken? •Look for 4-6 objectives Whom to interview: •Given the objectives who are the stakeholders? •Do you need background on these people before interviewing? •How many do you need to interview? •Good practice to forewarn interviewee, tell them what to expect, allay any doubts or concerns if possible • Decide on structure and questions: •Open-ended or closed questions •Structured, unstructured or semi-structured? • •Plan a logical flow for your questions if possible Reviewing related documents and materials: •Ask for reports, corporate newsletters, mission statements, job descriptions, user manuals •Observe the language and tone of the material e.g. authoritarian, liberal, rule-based, bureaucratic? •Sensitise yourself to the vocabulary used Additional tips for during interview: •Make good first impression, establish rapport, firm handshake •Explain purpose and objectives of meeting •Keep to plan, goals, time •Avoid leading questions and double-barreled questions •Tape recorder - Better, but get permission •Be pleasant but business-like •Correct any misapprehensions •Correct any confusion •End interview by summarising main points obtained • Additional tips for after interview: •Write-up interview while it is still fresh in your mind •Relate what you found to your objectives •Were the objectives achieved? •If not, who do you need to talk to or re-interview to achieve objectives?
List and briefly describe the five activities of system analysis
Gather detailed information: define requirements Prioritize requirements Develop user-interface dialogs Evaluate requirements with uses
Steps for Drawing an Activity Diagram
Identify the agents to create the appropriate swimlanes. 2. Follow the various steps of the workflow and then make appropriate ovals for the activities. 3. Connect the activity ovals with arrows to show the workflow. 4. Use a decision symbol to represent an either/or situation 5. Use synchronization bars for parallel paths
What types of stake holders should you include in fact finding?
Internal stakeholder: - those within the organization who interacts with the system or have a significant interest in its operation or success e.g.g employees external stakeholders: - those outside the organization control and influence eg.g suppliers/shipping occupancies Operational stakeholder: - those who regularly interact with a system in the course of their job or lives e.g. accountant interacts with accounting/ billing system, factory supervisor etc. Executive stakeholder: - who don't interact directly with the system, - but whom either uses information produced by the system or have a significant financial or other interest in its operation and success E.g. organization senior manager and board of directors, regulatory agencies etc. 2 that doesn't fit in neatly client: - person our a group that provides the funding for the project Eg.g senior management/ corporation's boards o directors - approve stage of the project and release funds Why is it in the team? need to provide a periodic status review to the clients throughout the development technical and support staff - who establish and maint the computing environment of the organization - provide users training, troubleshooting and related services - provide guidance ins such as area like prgaming language, computer platform - help the new system to fit within the organization existing technology architecture, application narchite and support environment
Prioritising Requirements? explain
Resources are always limited - so it is important to establish which requirements are more important for the system - this helps to determine the numbers, composition and ordering of project iteration high priority - early project iteration - analyst must be prepare to justify the scope of system - Sometimes: system requirements tend to explain as users make more suggestions = scope creep, this can be controlled if analysts priortise
semi structured questions are good for
Semi-structure questions have combination of both e.g. might start off with a general question then drill in and get more specific (i.e. a probe). They need more skill on the part of the interviewer.
structure questions are good for?
Structured questions are good for facts, history, detail. They save time, keeps control of the interview, use closed questions typically and do not give rich picture or explanations.
What is the purpose of an activity diagram?
UML diagram that describes user activities, the person or component that completes each activities and the sequential flow of these activities
What is
Unified Modelling Language • A general purpose visual modelling language • Designed to incorporate software engineering best practices - Human readable, both high level & low level - CASE support • UML does not give us any type of modelling methodology, UML itself just provides a visual syntax that we can use to construct models • UML is not a methodology
Who are vendors?
Vendors: Other companies, consulting firms that have experience with the same problems, or software firm that have packaged solutions for a particular business need.
What are stakeholders?
primary source of information for system requirements - all the people who have an interest in the successful implementation of the system - Each stakeholder group interacts with the system in different with their own perspective on system requirements Eg.: bookkeepers, accountant, manger, customers investors
what is workflow?
sequence of processing steps that completely handles one business transaction or customer request
What application architecture?
set if infomration systems ( the fsoftware applications) the organization needs to support its strategic plan.
