System Analysis and Design

Type of Feasibility

- operational - technical - Economical - Schedule

DFD: Numbering Levels

-Context Diagram Process labeled "0" -Level 0 Processes labeled 1.0, 2.0, 3.0, . -Level 1 Processes labeled 1.1, 1.2, 1.3, . -Level 2 Processes labeled 1.11, 1.12,...

Agile vs Traditional SDLC Models

1.Agile is based on the adaptive software development methods, whereas the traditional SDLC models like the waterfall model is based on predictive approach. 2.Predictive teams in the traditional SDLC models usually work with detailed planning and have a complete forecast of the exact tasks and features to be delivered in the next few months or during the product life cycle. 3.Predictive methods entirely depend on the requirement analysis and planning done in the beginning of the cycle. 4.Any changes to be incorporated go through a strict change management and prioritization. 5.Agile uses an adaptive approach where there is no detailed planning and there is clarity on future tasks only in respect of what features need to be developed. 6.The product is tested very frequently, through the release iterations, minimizing the risk of any major failures in future. 7.Customer Interaction is the backbone of the Agile methodology, and open communication with minimum documentation are the typical features of agile development environment. The agile teams work in close collaboration with each other.

Joint Application Development

1.Also known as Joint Application Design. 2.Used for requirement elicitation. 3.Group orientated. 4.Facilitated through workshop session.

Data Flow

1.Data flow allows to move from one the system to another like a cable in communication network. Data Flow can handle input-output data or both

Agile Model - Cons

1.Depends heavily on customers interaction, so of customers is not clear, team can be driven in the wrong direction. 2.Transfer of technology to new team members may be quite challenging due to lack of documentation. 3.There is a very high individual dependency,since there is minimum documentation generated. 4.Not suitable for handling complex dependencies.

Preparing for JAD Workshop

1.Establish rules and procedures. 2.Interview participants. 3.Gather materials. 4.Establish meeting agenda.

JAD Workshop

1.Facilitator follows agenda 2.Discuss high-level requirements. 3.Decisions through group consensus. 4.Unresolved open issues are documented. 5.Design specification is created.

Disadvantage of Waterfall Model:

1.High amount of risk and uncertainty. 2.Not good model for complex and object oriented project. 3.Poor model for long and ongoing project. 4.Not suitable for the projects where requirements are at a moderate to high risk of changing. 5.Cannot accommodate changing requirements.

Agile Manifesto Principles

1.Individuals and Interaction : In agile development, self-organization and motivation are important, as are interactions like co-location and pair programming. 2. Working Software: Demo working software is considered the best means of communication with the customers to understand their requirements, instead of just depending on documentation. 3.Customer Collaboration: As the requirement cannot be gathered completely in the beginning of the project due to various factors,continuous customer interaction is very important to get proper product requirement. 4.Responding to change: Agile development is focused on quick response to change and continuous development.

Agile Model -Pros

1.Is a very realistic approach to software development. 2.Promotes teamwork and cross training. 3.Functionality can be developed rapidly and demonstrated. 4.Resources requirements are minimum. 5.Suitable for fixed or changing requirements. 6.Delivers early partial working solutions. 7.Good model for environments that change steadily. 9.Minimal rules, documentation easily employed. 10.Little or no planning required. 11.Easy to manage. 12.Gives flexibility to developers.

Spiral Model - Pros

1.It allows elements of the product to be added in,when they become available or know. 2.This assures that there is no conflict with previous requirement and design. 3.Requirements can be captured more accurately. 4.Users see the system early. 5.Development can be divided into smaller parts and the risky parts can be developed earlier which helps in better risk management.

WaterFall Model

1.It is also referred to as a Linear-Sequential Life Cycle Model. 2.each phase must be completed before the next phase can begin and there is no overlapping in the phases. 3.the whole process of software development is divided into separate phases

JAD Disadvantage

1.JAD requires the team to have substantial experience in the problem domain. 2.JAD offers quick solution to problem, so often these problems are considered too quickly. 3.Members of large meeting can become subject to "groupthink." 4.JAD can be logistically difficult if there are a large number of stakeholders spread across different time zones.

Spiral Model-Cons

1.Management is more complex. 2.End of the project may not be known early. 3.Spiral may go on indefinitely. 4.Not suitable for small or low risk projects and could be expensive for small projects. 5.Large numbers of intermediate stages requires excessive documentation.

DFD Symbols

1.Process - performs some action on data, such as create, modify, store, delete, etc. Can be manual or supported by computer. 2.Data store - information that is kept and accessed. May be in paper file folder or a database. 3.External entity - is the origin or destination of data. Entities are external to the system. 4.Data flow - the flow of data into or out of a process, datastore or entity

Application of Waterfall Model:

1.Requirement are very well document,clear and fixed. 2.Product definition is stable. 3.Technology is understood and its not dynamic. 4.There are no ambiguous requirements. 5.The project is short.

Advantages of Waterfall Model:

1.Simple to understand and use. 2.Easy to manage due to the rigidity of the model.Each phase has specific deliverables and a review process. 3.Phases are processed and complete one at a time. 4.Works well for smaller projects where requirement are very well understood. 5.Clearly defined stages. Process and result are well document

JAD Team Roles

1.Sponsor: One or more individuals. 2.Facilitator: There can be only one. 3.Participant Multiple individuals based scope and complexity. 4.Scribe Typically one individual

Spiral Model Application

1.When there is a budget constraint and risk evaluation is important. 2.For medium to high risk projects. 3.Customer is not sure of their requirement which is usually the case. 4.Significant changes are expected in the product during the development cycle.

Spiral Model

1.combination of iterative development process model and sequential linear development model ie Waterfall Model. 2.It allows incremental release of the product or incremental refinement through each iteration around the spiral. 3.The spiral model has four phases. A software project repeatedly passes through these phase in iterations called spiral.

Abstraction

1.concept of hiding the internal details and describing things in simple terms. 2.For example, a method that adds two integers. 3.The method internal processing is hidden from outer world.

Object Oriented Analysis(OOA)

1.describes an information system by identifying things called Objects. 2.Object represent is a real person,place,event or transaction. 3.For eg. When a patient makes a appointment to see a doctor,the patients is an object,the doctor is an object,and the appointment itself is a object. 4.Object oriented analysis is a popular approach that sees a system from the view point if the object themselves as they function or interact. 5.The end product of object-oriented analysis is an object model.

Agile Model

1.focus on process adaptability and customer satisfaction by rapid delivery of working software product. 1.break the product into small incremental builds. 2.These builds are provided in iterations. Each iteration typically lasts from about one to three weeks. 3.Every iteration involves cross functional teams working simultaneously on various areas like - Planning, Requirements Analysis, Design ,Coding, Unit Testing and Acceptance testing 5.At the end of the iteration, a working product is displayed to the customer and important stakeholders. 7.In agile,the tasks are divided to times box(small time frames) to deliver specific features for a release. 8.The agile thought process has started early in the software development and started become popular with time due to its flexibility and adaptability. 7.Agile is set of values and principals.

What is a System?

A system is a set of related components that produces a specific result. Constraints of a System: ●It must have some structure and behaviour which is designed to achieve a predefined goal. ●Interconnectivity and interdependence must exist among the system components. ●The objective of the organization have a higher priority than the objective of its subsystems

Polymorphism

If one task is performed by different ways,

4 Phases of Spiral Model

A.Identification: ●This phase starts with gathering the business requirement in the baseline spiral. ●In the subsequent spirals as the product matures,identification of system requirement, subsystems requirement and unit requirement are all done in this phase. ●This phase also includes understanding the system requirements by continuous communication between the customer and the system Analyst. B.Evaluation and Risk Analysis: ●Risk Analysis includes identifying,estimating and monitoring the technical feasibility and management risks, such as cost overrun. ●After testing,at the end of first iteration,the customers evaluates the software and provide feedback. ●Based on the customer evaluation,the software development process enters the next iteration and subsequently follows the linear approach to implement the feedback suggested by the customer. ● The process of iteration along the spiral continues throughout life of the software. C. Design: ●The design phase starts with conceptual design in the baseline spiral and involves architectural design, logical design of modules, physical product design and the final design in the subsequent spirals. D. Construct or Build: ●The construct phase refers of production of the actual software product at every spiral. ●In the baseline spiral, when the product is just thought of and the design is being developed of a POC(proof of concept) is developed in this phase to get customer feedback

Sequential Phases

A.Requirement Gathering and analysis: ●All possible requirements of the system to be developed are captured in this phase and documents in a requirement specification document. B.System Design: ●The requirement specification from the first phase are studied in this phase and the system design is prepared. ●This system design helps in specifying hardware and system requirement and helps in defining the overall system architecture. C.Implementation: ●With inputs from the system design, the system is first developed in small programs called units ●Each unit is developed and tested for its functionality, which is referred to as unit testing D.Integration and Testing: ●All the units developed in the implementation phase are integrated into a system after testing of each unit. ●Post integration the entire system is tested for any faults and failures. E.Deployment of System: ●Once the functional and non-functional testing is done; the product is install in the customer environment or released into the market. F.Maintenance: ●There are some issues which come up in the client environment. ●To fix those issues,patches are released. ●Also to enhance the product some better versions are released. ●Maintenance is done to deliver these changes in the customer environment

Encapsulation

Binding (or wrapping) code and data together into a single unit

JAD Advantages

JAD sessions help bring experts together giving them a chance to share their views, understand views of others, and develop the sense of project ownership. 2. JAD provides a structured approach to requirements elicitation that can help reduce development errors.

Scrum Ceremonies: Sprint Planning Meeting

Sprint Planning Meeting: ●Who I.Team,Scrum Master and Product Owner. ●Agenda i.Discuss top priority product backlog items. ii.Team select which to do. ●Why i.Know what will be worked on Understand it enough to do it

Preliminary Investigation Overview

System Analysts conduct a PIO to study the system request and commend specific action. Gathers facts about the problem/ opportunity, project scope, constraints, benefits, estimated development time and costs.

Schedule

project will be implemented in a accepted time frame. must consider interaction between time and and cost

Object oriented Programming terms:

a.Abstraction b.Encapsulation c.Inheritance Polymorphism

Technical

focused on gaining an understanding of the present technical resources of the organization and their applicability to the expected needs. - evaluation of hardware and software and how it meets the needs of the proposed system - based on an outline design of the system requirement

Data Flow Diagram

graphical tool that allows system analysts (and system users) to depict the flow of data in an information system. one of the methods that system analysts use to collect information necessary to determine information system requirements. intended to serve as a communication tool among- systems analysts, end users, database designers, system programmers and other members of the project team

Operational

means that a proposed system will be used effectively after it has been developed - if a user has difficulty with the new system, it will not produce the expected benefits

Economic

means that the projected benefits of the proposed system outweigh the estimated costs or "Total Cost of Ownership" MUST CONSIDER: Staff hardware software

Feasibility Study

measures the likelihood to complete a project successfully including all factors

Inheritance

one object acquires all the properties and behaviors of a parent object

DFD 2

● goes one step deeper into parts of Level 1. ●It may require more text to reach the necessary level of detail about the system's functioning.

Management Information System(MIS)

●A MIS is an information system that uses the data collected by transaction processing system and uses this data to create reports in a way that managers can use it to make routine business decision in response of problems. ●An MIS integrates the information flow between functional area where systems tend to support a single functional area. ●MIS caters to the information needs of all levels of management where system focus on operational-level support ●Operational Roles: Supervisors and Team Leaders Advantages: ●Flexible and can be adapted to meet changing information needs of organization. ●Provides operational, tactical and strategic-level managers with easy access to timely but for the most part, structured information.

Critical Path Method (CPM)

●A critical path is a series of the task which, if delayed, would affect the completion date of the overall project. ●If any task on the critical path falls behind the schedule, the entire project will be delayed. ●To overcome this we can do Time Cost trade.

JAD Participants

●Adhere to workshop Rules and procedures. ●Attend all workshop session. ●Actively participate in sessions. ●Discuss high-level requirements. ●Propose requirements and specifications ●Work towards consensus on decisions.

Transaction/Data Processing System

●Are concerned with transaction handling and record keeping. ●Data are entered and stored in a file format, and stored files are updated during routine processing. ●Periodic outputs include action documents(invoice) and scheduled reports, primarily for operational-level managers. ●Organizational Roles: Operational Employees Drawbacks: ●Inflexible ●Cannot accommodate data processing or information needs that are not already built into system.

DFD 0

●Context Diagram. ●It's a basic overview of the whole system or process being analyzed or modeled. ●It's designed to be an at-a-glance view, showing the system as a single high-level process, with its relationship to external entities. It should be easily understood by a wide audience, including stakeholders,business analysts, data analysts and developers

Scrum Roles: Product Owner

●Define the features of the product. ●Makes scope vs schedule decisions. ●Responsible for achieving financial goals of the project ●Prioritize the product backlogs ●Adjust features and priority every sprint, as needed ●Accept or reject work result

JAD Scribe

●Documentation 1.Record agreed upon requirements and specification. 2.Record all open issues 3.Gather created documents and materials Write the requirement document

Which type is Better?

●Gantt charts breaks project into smaller tasks and highlight scheduling constraints. ●Project manager use Gantt charts while project is happening-they schedule task by dates and show how much work has been completed. ●Every activity is represented with a bar that stretches from the start date to the end date of activity. ●Gantt offers a valuable snapshot view of the project, PERT charts are more useful for scheduling, monitoring and controlling the actual work. ●PERT chart is generally used before a project begins to plan and determine the duration of each task-so they don't have to show the actual dates of the project. ●They also do a better job of showing whether certain tasks need to be completed in order or whether they can be completed simultaneously.

JAD: Fecilitators

●Is a neutral party ●Preparation for JAD workshop ●Facilitate Workshop session ●Follow Agenda ●Keep team focused ●Resolve conflicts

Executive Information System(EIS)

●It is also known as Executive Support System(ESS) ●This facilitates and supports senior executive information and decision-making needs. ●It provide easy access to internal and external information relevant to organizational goals. ●It is commonly considered a specialized form of decision support system ●EIS emphasizes graphical displays an easy to user interface. ●Organizational Roles: Top Managers Advantages: ●Easy for upper-level executives to use,extensive computer experience is not required in operations. ●Information that is provided is better understood. ●Offer efficiency to decision makers Provides strong drill-down capabilities to better analyze the given information

Role of SWOT Analysis

●It is widely used technique to perform structured identification and analysis of the factors that will decide the outcome of any proposal, project, product or business case. ●SWOT analysis is easy conduct, gives a lot of insights in a relatively small time and be applied to a whole lot of situation.

Daily Scrum

●Parameters i.Daily ii.15-minutes iii.Stand-up ●Not for problem solving i.Team members, ScrumMaster, Product owner;can talk ●Helps avoid unnecessary meetings ●Three question answer by each team members: i.What did you yesterday? ii.What will you do today? iii.What are obstacles are in you way?

Scrum: Sprint Retrospective:

●Periodically take a look at what is and is not working. ●Typically around 30 minutes. ●Done after every sprint. ●Whole team participates. i.ScrumMaster ii.Product Owner iii.Team

Risk Management

●Project risk management is the process of identifying, analyzing and then responding to any risk that arises over the life cycle of a project to help the project remain on track and meet its goal. ● 5 steps in risk management process: ○Identify the risk ○Analyze the risk ○Evaluate or Rank all risk ○Treat the risk ○Monitor and Review the risk

Scum Roles: Scrum Master

●Responsible for enacting Scrum values and practices. ●Remove impediments. ●Coaches the team to their best possible performance. ●Helps improve team productivity in any way possible. ●Enable close cooperation across all roles and functions ●Shields the team from external interference

Software Development Lifecycle (SDLC)

●System Planning ●System Analysis ●System Design ●System Implementation ●System Support and Security

Scrum: Sprint Review

●Team represents what is accomplished during the sprint ●Typically takes a form of a demo of new features or underlying architecture. ●Informal: i.2 hrs prep time rule ii.No slides ●Whole team participates

Scrum sprint planning

●Team selects items from the product backlog they can commit to completing ●Sprint backlog is created. i.Tasks are identified and each is estimated (1-16 hrs) ii.Collaboratively,not done alone by ScrumMaster ●High level design is considered

Gantt Chart

●The Gantt chart is one of the most popular scheduling tools in project management. It's a horizontal bar chart that shows progress on a project schedule. ● A gantt charts also can simplify a complex project by combining several activities into a group task that contain subsidiary tasks. ●This allows a complex project to be viewed as a set of integrated modules. ●They also help you view the start and end dates of a project in one simple view.

Work Breakdown Structure

●The Work breakdown structure (WBS) is an organizational chart used for project planning. ● It organizes the work to be done on a project by breaking down the project into its major components referred to as Modules. ●These components are then subdivided into more detailed subcomponents, which are further broken down into activities & finally, into individual task. ●The end result is an organizational structure of the project made up of different levels, with the overall project at the top level and the individual tasks at the bottom.

DFD:Adding Levels of details

●The highest level, called the context diagram, is only an overview. More detail is typically needed for system analysts. ●We add detail to a DFD by creating "levels". The first level added after the context diagram is called level "0". ●Each new level breaks apart one process and "decomposes" the single process into a new, more detailed DFD. A complete DFD can have many (up to 6 or 7) levels depending on the complexity of system. ●Breaking the DFD into levels is referred to as "Decomposition".

What do system analysts do?

●They are valid member of IT department. ●They help the team to plan, develop and maintain information system. ●System Analyst transform business requirement to IT project. ●They can also report to specific user area such as marketing, sales or accounting. ●They will be asked to document business process, test hardware and software packages, design input screen, train users and plan e-commerce sites. ●They also manage IT projects, including tasks resources, schedules and costs.

Scrum Roles: Team

●Typically 5-9 people ●Cross-Functional. I.Programmers,testers,user experience designer etc. ●Teams are self-organizing I.Ideally,no titles but rarely a possibility. ●Membership should change only between sprints.

Physical DFD

●dependent. It shows which functions are performed. ●It provides low level details of hardware, software, files, and people. ●It depicts how the current system operates and how a system will be implemented.

Decision Support System (DSS)

●helps make decision by working and analyzing data that can generate statistical projection and data models. ●This system gives support rather than replacing a managers judgement while improving the quality of managers decision. ●A DSS helps solve problems while using external Data. ●Organizational Roles: Middle Managers and Knowledge Workers

DFD Logical

●is implementation independent. It focuses only on the flow of data between processes. ●It explains events of systems and data required by each event. ●It shows how business operates; not how the system can be implemented.

DFD 1

●provides a more detailed breakout of pieces of the Context Level Diagram. You will highlight the main functions carried out by the system, as you breakdown the high-level process of the Context Diagram into its subprocesses