BTEC Unit 9 Software Development & Lifecycle, Study notes of Computer science

Download BTEC Unit 9 Software Development & Lifecycle and more Study notes Computer science in PDF only on Docsity!

Submitted by

SOFTWARE DEVELOPMENT &

LIFECYCLE

Unit 9

Table of Contents

Introduction

I am working in eEsigners Inc. as a trainee analyst and I have been provided with the opportunity to be appointed as an Assistant System Analyst. This opportunity has come with a

• Introduction.................................................................................................................................................
  • Different Software Development Lifecycles................................................................................................
• Understanding and use of software development models.......................................................................... - Predictive................................................................................................................................................. - Waterfall Model:...................................................................................................................................... - Usage:...................................................................................................................................................... - Advantages:............................................................................................................................................. - Prototype Model:.................................................................................................................................... - Usage....................................................................................................................................................... - RAD Model:.............................................................................................................................................. - Usage:...................................................................................................................................................... - Advantages:.............................................................................................................................................
• Adaptive......................................................................................................................................................
• Risk management in the Spiral lifecycle model........................................................................................... - Spiral Model............................................................................................................................................. - Usage....................................................................................................................................................... - Risk Management.................................................................................................................................... - Agile Model:............................................................................................................................................. - DSDM:......................................................................................................................................................
• Introduction.................................................................................................................................................
• Importance and Purpose of a feasibility report...........................................................................................
• key drivers that play important role in proposed technical solution for software development project.... - Reliability................................................................................................................................................. - Effectiveness.......................................................................................................................................... - Integrity................................................................................................................................................. - Usability................................................................................................................................................. - Product Revision Quality Factors........................................................................................................... - Maintainability....................................................................................................................................... - Adaptability........................................................................................................................................... - Testability..............................................................................................................................................
• Components of a feasibility report............................................................................................................
  • 1. The venture scope:............................................................................................................................
  • 2. The current analysis:..........................................................................................................................
  • 3. The requirements:.............................................................................................................................
  • 4. The approach:....................................................................................................................................
• Assess the impact of different feasibility criteria on a software investigation...........................................
  • Technical Impact....................................................................................................................................
  • Operational Impact................................................................................................................................
  • Economic effect.....................................................................................................................................
  • Social Impact..........................................................................................................................................
• Introduction...............................................................................................................................................
• Software investigation to meet a business need.......................................................................................
  • Purpose..................................................................................................................................................
  • Existing Hardware and Software:...........................................................................................................
  • Recognizable proof of issues with the present system:.........................................................................
  • Investigation of expenses and advantages of the new system:.............................................................
  • Meetings:...............................................................................................................................................
• User Requirements....................................................................................................................................
  • Biometric System:..................................................................................................................................
  • System Requirement.............................................................................................................................
• Tools/techniques to carry out a software investigation and supporting documentation..........................
• Identify requirements................................................................................................................................
  • Stakeholders:.........................................................................................................................................
  • Requirements Identification:.................................................................................................................
  • Requirements Specification:..................................................................................................................
  • Scope.....................................................................................................................................................
  • Inputs.....................................................................................................................................................
  • Outputs..................................................................................................................................................
  • Requirements Specification:..................................................................................................................
  • Processes and process descriptors........................................................................................................
  • Consideration of alternate solutions and security considerations.........................................................
  • Quality assurance..................................................................................................................................
• Constraints.................................................................................................................................................
  • Costs......................................................................................................................................................
  • Organizational Policies...........................................................................................................................
• Report Documentation..............................................................................................................................
  • Background information........................................................................................................................
  • Problem statements..............................................................................................................................
  • Data collection process and summary...................................................................................................
  • Recommendations.................................................................................................................................
  • Appendices............................................................................................................................................
• Suitability of software behavioral design techniques................................................................................
• Techniques:...............................................................................................................................................
  • Flowchart...............................................................................................................................................
  • Basic Flowchart Symbols........................................................................................................................
  • Four Flowchart Structures.....................................................................................................................
• Pseudocode...............................................................................................................................................
  • Advantages & Disadvantages.................................................................................................................
• Differentiate between a finite state machine (FSM) and an extended-FSM..............................................
  • Finite State Machine..............................................................................................................................
  • Extended-FSM........................................................................................................................................
• References.................................................................................................................................................

What is SDLC?

SDLC is a procedure pursued for a software venture, inside a software company. It comprises of a point by point plan portraying how to create, maintain and change or upgrade specific software. The life cycle characterizes a strategy for enhancing the nature of software and the general development process.

Importance of SDLC

SDLC is vital in light of the fact that it separates the whole life cycle of software development along these lines make it easier to assess each part of software development and furthermore makes it easier for programmers to work simultaneously on each stage. Planning and Analysis is the most imperative phase of SDLC. Numerous organizations just spend 10-15 % on these two stages and at last they fail because they didn't design and plane the product that was expected to invent. Investing more time in these two stages would decrease the additional time and decrease costs by creating a destitute product. This stage must not be overlooked to produce more business and wanted outcomes.

Different Software Development Lifecycles

The procedure of a software development lifecycle is as under:  Planning Business requirements are assembled in this stage. This stage is the principle focal point of the project supervisors.  Analysis Software Development Life Cycle starts with Requirement Analysis stage, where the stakeholders talk about the requirements of the product that should be created to accomplish an objective.  Design In this stage the system and software configuration are set up from requirement details which were examined in the principal stage. System design helps in indicating equipment and system requirements.

Advantages:

 Simple to organize undertakings.  Process and results are all around reported.  Structures approach.

 Prototype Model:

Prototype model is a working model of software with some constrained usefulness. This model does not generally hold the precise rationale utilized in the real software application and is an additional push to be considered under exertion estimation.

Usage

Prototyping is utilized to permit the users assess developer proposition and give them a shot before usage. It additionally comprehends the necessities which are user explicit and might not have been considered by the developer amid item plan. Different types of prototype model:  Evolutionary Prototyping  Rapid Prototyping  Incremental Prototyping  Extreme Prototyping

 RAD Model:

The RAD (Rapid Application Development) model based on prototyping and iterative improvement with no explicit planning included. In the RAD model, the practical modules are created in parallel as models and are coordinated to make the complete product for quicker item delivery. Since there is no complete preplanning, it makes it less demanding to consolidate the changes inside the development procedure. RAD model disperses the analysis, design, incorporate and test stages with a progression of short, iterative development cycles. Following are the different phases of the RAD Model:

Usage:

 RAD model to be utilized just when a system can be modularized to be conveyed in an incremental way.

 RAD model to be utilized if there is a high accessibility of designers for modeling.

Advantages:

 Changing necessities can be suited.  Emphasis time can be short with utilization of powerful RAD tools.

Adaptive

 Spiral Model  Agile Model  DSDM Model

Risk management in the Spiral lifecycle model.

 Spiral Model

It is joining components of both plan and prototyping-in-stages, with an end goal to consolidate focal points of best down and base up ideas. This model of development consolidates the highlights of the prototyping model and the waterfall model. The spiral model is used for extensive, costly, and complex project. This model uses a considerable lot of same stages from the waterfall model.

Usage

It is utilized in the extensive applications and systems which worked in small stages or sections.

Risk Management

Risk managed in spiral model in serval ways:  The transformative prototyping spirals that go for settling execution and UI related risks. These spirals help in decreasing real risks previously continuing into the advancement procedure.  The risk analysis phase at each cycle that goes before each stage of the waterfall stages in cause of:

Introduction

Having completed the first stage of my promotion to the position of Assistant System Analyst, now I am assigned with the requirements for the Stage 2. The stage 2 requires to demonstrate the knowledge and ability to conduct requirement gathering for a project and prepare a feasibility study based on my assessment and evaluation of those requirements.

Importance and Purpose of a feasibility report.

The motivation behind feasibility study is to decide the components that will make the business opportunity that was displayed in the business case a triumph. Incorporated into the project feasibility report will be the investigation of the primary focal point of the business opportunity alongside the elective ways it could pursue. By gathering this information, the board would then be able to settle on an educated choice on which way ought to be sought after so as to make the most productive income stream for the organization. To get a venture feasibility consider began, the utilization of a plausibility think about layout is the most productive intends to advancing this report so a last draft would then be able to be actualized. The format will as of now have the record delineated with the suitable areas made.

key drivers that play important role in proposed technical

solution for software development project

The different variables, which impact the software, are named as software factors. They can be comprehensively isolated into two classes. The primary class of the components is of those that can be estimated straightforwardly, for example, the quantity of consistent errors, and the second classification clubs those elements which can be estimated just in a roundabout way. For instance, viability however every one of the elements is to be estimated to check for the substance and the quality control.

 Reliability

Reliability necessities manage benefit failure. They decide the greatest permitted failure rate of the software framework, and can allude to the whole framework or to at least one of its different capacities.

 Effectiveness

It manages the equipment assets expected to play out the diverse elements of the software framework. It incorporates preparing abilities (given in MHz), its stockpiling limit (given in MB or GB) and the information correspondence capacity (given in MBPS or GBPS). It likewise manages the time between reviving of the system's versatile units, for example, data system units situated in convenient PCs, or meteorological units set outside.

 Integrity

This factor manages the product framework security, that is, to counteract access to unapproved people, likewise to recognize the gathering of individuals to be given perused and in addition compose allow.

 Usability

Usability prerequisites manage the staff assets expected to prepare another worker and to work the software system.

Product Revision Quality Factors

As per McCall's model, three software quality elements are incorporated into the item update class. These elements are as per the following −

 Maintainability

This factor considers the endeavors that will be required by clients and upkeep faculty to distinguish the explanations behind software failures, to address the failures, and to confirm the achievement of the adjustments.

 Adaptability

This factor manages the capacities and endeavors required to help versatile upkeep exercises of the software. These incorporate adjusting the present software to extra conditions and clients without changing the software.

 Testability

Testability necessities manage the testing of the software framework and with its activity. It incorporates predefined transitional outcomes, log documents, and furthermore the programmed diagnostics performed by the software system preceding beginning the system, to see if all parts of the system are in working request and to get a report about the distinguished shortcomings.

Components of a feasibility report.

A feasibility report can be completed for everything without exception be it for software advancement, at the season of securing or for any such venture. On the off chance that you are anticipating directing a possibility contemplate, following feasibility report components:

1. The venture scope:

The initial step is to unmistakably characterize the business issue/opportunity that must be tended to. The undertaking degree needs to authoritative and to the point. Make a point to likewise characterize

 Technical Impact

The development of data and the reliance on it have made ready for the data society and in this way the learning society. Data has dependably been prime factor for the improvement of society and is frequently viewed as an imperative national asset. Data administrations attempt to meet this target. Data has turned out to be vital piece of our lives and ought to be accessible when required. Data administrations are created utilizing new devices and systems to encourage the correct clients to the correct data (Khodeh and Dhar, 2002).

 Operational Impact

Associations that are lean in their focused race are those that exceed expectations in their tasks in manners that are completely tuned with their vital aims. This enables them to augment the operational effect of their methodology and to accomplish supported elite.

 Economic effect

Economic effect estimation has turned into a ground-breaking and convincing device for those hoping to catch and proof the money related advantages that can result from the facilitating of a noteworthy occasion. Estimating financial effect not just permits open area bodies to assess their monetary rate of return, however it additionally exhibits how organizations drive financial advantages - permitting organization coordinators create rehearses which augment these advantages.

 Social Impact

Social effects are probably not going to occur by shot and should be overseen on the off chance that they are to happen. The beginning stage in conveying explicit social effects is for an organization to have plainly expressed points and destinations that depict the conveyance systems by which the arranged effects will happen. The explanation behind estimating social effects can regularly be connected specifically to the points and goals of the occasion funders. It is essential to perceive that delightful the targets of a partner ought not offer the main impetus to gauge the social effects of occasions. Any occasion coordinator should wish to see how their occasion impacts on the recognitions and conduct of individuals (regardless of whether straightforwardly or in a roundabout way).

Introduction

After the successful completion of the Stage 2 of my assignment, the company has bestowed the designation of Assistant System Analyst. I am finally required to complete the Stage 3 which requires the actual demonstration of the knowledge and skillset in the field of System Analysis.

Software investigation to meet a business need

The educational system project was distributed by the Edesigners.inc to make a Sdlc display and to watch that how the application will be assembled. The SDLC are arrangement of exercises to see systems utilized inside associations.

Purpose

The school need to actualize another enlistment system utilizing biometric unique mark gadget on the grounds because the current system does not bolster this system.

 Existing Hardware and Software:

Our group went to the personnel investigated which systems are being utilized by the school and where the equipment would need to supplanted.

 Recognizable proof of issues with the present system:

The present system probably won't have office for contributing information by standardized identification.

 Investigation of expenses and advantages of the new system:

What will it cost as far preparing staff, purchasing new gear equipment and software for new system?

 Meetings:

Meeting with school administrators and staff on how the current system functions and what are the issues, what conceivable enhancements could be made.  Perceptions: How the workers communicate with the system, what do they do? How would they utilize the framework?  Feasibility report: This is the way toward proceeding with the new framework after the examination work and attainability report has been created.

User Requirements

Biometric System:

 Biometric system will control the physical access of students.  Other than that, with finger print recognition system management will be able to log and track students’ timings to respective classes. Student Portal:

 During output design, developers identify the type of outputs needed, and consider the necessary output controls and prototype report layouts.

Requirements Specification:

Processes and process descriptors

 Process framing defines the process boundaries, the major activities, the actors, key metrics, the case for action, and the vision for the future process.  The process framing can then be used to draft key business requirements for the new system.

Process descriptor

 A set of information that defines the status of resources allocated to a process.  When a system contains a number of processes, any of which may be active at any one time, there will be for each process a descriptor defining the status of that process. Consideration of alternate solutions and security considerations  It is important that multiple alternatives be considered. Potential solutions (decision alternatives) should be adequately described to make them understandable to everyone involved in the development.  All of these business processes and information require some level of security processing. One type of security is required to protect the client, another to protect the corporation.

Quality assurance

 Software quality assurance is the process of evaluating how well software meets the needs of the end customer.  QA revolves around three pillars: reliability, efficiency, and flexibility. In order for software to be useful, it needs to work consistently, complete tasks quickly, and be useful in a variety of situations.  Furthermore, good software also needs internal quality controls, making sure the underlying code is clean and practical.

Constraints

Constraints: specific to activity e.g.

 Costs

The process of isolating and estimating costs and benefits system costs and benefits from the system

 Organizational Policies

Whether the proposed system is consistent with the organization’s strategic objectives?

Report Documentation

 Background information

About the client business/organization and current IT system.

 Problem statements

Problem definition: On receiving a request from the user for systems development, an investigation is conducted to state the problem to be solved.

 Data collection process and summary

Process of gathering and measuring information

 Quantitative Data: These are data that deal with quantities, values or numbers, making

them measurable.

 Qualitative Data: These data, on the other hand, deals with quality, so that they are

descriptive rather than numerical in nature.

 Recommendations

E.g. features to be implemented in the new system.

 Appendices

An appendix contains supplementary material that is not an essential part of the text itself but which may be helpful in providing a more comprehensive understanding of the project.

Suitability of software behavioral design techniques

Techniques:

Flowchart

A flowchart is a diagram that depicts the “flow” of a program. The figure shown here is a flowchart for the pay-calculating program:

Basic Flowchart Symbols

There are three types of symbols in this flowchart:  Rounded rectangles  Parallelograms  A rectangle Each symbol represents a different type of operation

Pseudocode

Flowcharts were the first design tool to be widely used, but unfortunately, they do not reflect some of the concepts of structured programming very well. Pseudocode, on the other hand, is a newer tool and has features that make it more reflective of the structured concepts.

Advantages & Disadvantages

Differentiate between a finite state machine (FSM) and an

extended-FSM.

Finite State Machine

A Finite State Machine is a model of calculation dependent on a theoretical machine made of at least one states. Just a single condition of this machine can be dynamic in the meantime. It implies the machine needs to progress starting with one state then onto the next in to perform distinctive activities. Usage:  Vending Machines  Traffic Lights  Video Games  Text Parsing  CPU Controllers

Extended-FSM

Extended Finite State Machines (EFSMs) give an incredible model to the induction of useful tests for programming frameworks and conventions. Numerous EFSM based testing issues, for example, change testing, blame finding, and test induction include the deduction of info successions that recognize arrangements of a given EFSM detail.

References