Criminal Record Management System In the Perspective of Somalia

INDEX

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTEENTS

LIST OF FIGURES

LIST OF TABLES

LIST OF ABBREVIATIONS

CHAPTER 1 INTRODUCTION
1.1 Introduction
1.2 Motivation
1.3 Aims and Objective
1.4 Overview of the Project
1.5 Summary

CHAPTER 2 LITERATURE REVIEW
2.1 Introduction
2.2 Background
2.3 Some Related Works
2.4 Summary

CHAPTER 3 METHODOLOGY
3.1 Introduction
3.2 Methodology
3.3 Software Development Life Cycle (SDLC)
3.3.1 Feasibility Study
3.3.2 Requirement Study
3.3.3 System Analysis
3.3.4 System Design
3.3.5 Coding
3.3.6 Testing
3.3.7 Acceptance
3.4 Waterfall Software Development Methodology
3.5 Waterfall Model Application
3.6 Summary

CHAPTER 4 ANALYSIS
4.1 Introduction
4.2 Requirement Engineering
4.3 Requirement Engineering Process
4.3.1 Feasibility Study
4.3.2 Requirement Gathering
4.3.3 Software Requirement Specification
4.3.4 Software Requirement Validation
4.4 Software Requirement for Development
4.5 Hardware Requirement For Use
4.6 Software Requirement for Use
4.7 Use Case
4.7.1 Characteristic associated with use cases
4.7.2 The steps in designing use cases
4.8 Use case Diagram
4.9 Block Diagram
4.10 Flowchart
4.10.1 Definition
4.10.2 Necessity to Use a Flowchart
Summary

CHAPTER 5 SYSTEM DESIGN
5.1 Introduction
5.2 System Design
5.3 System Context Diagram (SCD
5.4 Data Flow Diagram
5.4.1 Data Flow Diagram
5.4.2 Types of DFD
5.4.3 DFD Components
5.5 Data Design
5.5.1 Entity Relationship
5.5.2 The used Elements of E-R diagram
5.5.3 E-R Diagram
5.6 Activity Diagram
5.7 Summary

CHAPTER 6 IMPLEMENTATION
6.1 Introduction
6.2 Software implementation
6.3 User Interface Design
6.4 Summary

CHAPTER 7 TESTING AND PERFORMANCE EVALUATION
7.1 Introduction
7.2 Software Testing
7.2.1 Verification
7.2.2 Validation
7.3Basics of Software Testing
7.3.1 Black Box Testing
7.3.2 White Box Testing
7.4 Types of Testing
7.4.1 Beta Testing
7.5 Test Example
7.6 Summary

CHAPTER 8 APPLICATION
8.1 Introduction
8.2 About the Application
8.3 Features of the Software
8.4 Users of the Project
8.5 Summary

CHAPTER 9 RESULT AND DISCUSSION
9.1 Result
9.2 Discussion
9.3 Summary

CHAPTER 10 CONCLUSION
10.1 Conclusion
10.2 Limitation of the Project
10.3 Future Scope and Plan

REFERENCES

APPENDIX A
Screenshots

APPENDIX B
Source Code

ACKNOWLEDGEMENT

Thanks to Allah, the almighty for giving his blessings and mercy to work hard for completing this project. I would like to thank our honorable teachers at the Department of Computer Science & Engineering, Southern University Bangladesh for their cordial help and support throughout honoree course here. I would like to express our sense of gratitude and indebtedness to our respected project supervisor, Professor Dr. Md. Nurul Mustafa the honorable professor, Department of Computer Science & Engineering, Southern University Bangladesh, and co- supervisor, Mr. Mohammad Jahangir Alam, Assistant Professor, Department of Computer Science & Engineering, Southern University Bangladesh for their valuable guidance, generous advice, endless encouragement and unfilled enthusiasm giving throughout the research and preparation of the entire project. I would also thankful to my classmates for their helpful suggestions throughout the project.

I would like to convey my deepest gratitude to my father, Jamal Mohamed Barrow and my mother, Fadumo Sharif Munye for their unconditional love and indulgence at the moment of triumph turmoil.

I express deep and sincere gratitude to Nuurto Omar, Niama Omar, Mustafa Jamal, Mohamed Jamal, Rukia Mohamed, Zeynab Ali, Jahid Hassan, Shaiful Alam, Fadumo Ramadan, whose guidance, encouragement, suggestion and very constructive criticism have contributed immensely to the evolution of my ideas on the project.

ABSTRACT

The project Criminal Record Management System in the perspective of Somalia is a Criminal record management system that uses to record crime activities of criminals. It can be used to report crime activities. This project is mainly useful for law and enforcement agencies in Somalia. The law and enforcement authority can preserve records of the criminals and search any criminal using the system. This is an online web application with database system in which police will keep the record of criminals who have been arrested. We have used HTML, JavaScript, CSS, PHP, MySql and Bootstrap to develop this project. We also used binary search algorithm to find a criminal from database. The project’s interface is very user friendly and helpful for authority.

LIST OF FIGURES

Fig. 3.1 Software Development Life Cycle (SDLC)

Fig. 3.2 Waterfall Software Development Methodology

Fig. 4.1 Requirement Engineering Process Model

Fig 4.2 Use case Diagram for CRMSS

Fig. 4.3 Block Diagram for CRMSS

Fig. 4.4 Flowchart for CRMSS

Fig. 5.1 System Context Diagram (SCD) of CRMSS

Fig. 5.2 Level 1 Data Flow Diagram

Fig. 5.6 E-R Diagram of CRMSS

Fig. 5.7 Activity Diagram of Admin

Fig. 5.8 Activity Diagram of Sub-admin

Fig. 5.9 Activity Diagram of Police

Fig. 5.10 Activity Diagram of Court

Fig. 6.1 Create An account

Fig 6.2 Admin Home Page

Fig 6.3 Crime Information Report

Fig. 6.4 Criminal List Report

Fig. 6.5 Sub-admin Home Page

Fig. 6.6 Police-user Home Page

Fig. 6.7 Court-user Home Page

Fig. 6.8 Police List Report

Fig. 9.1 Admin Page

Fig. 9.2 Login Page

Fig. 9.3 Police list

Fig. 9.4 Police Details

Fig. 9.5 Criminal List

Fig. 9.6 Criminal Details

Fig. 9.7 Crime List

Fig. 9.8 Crime Details

LIST OF TABLES

Table 7.1 Different Types of Test Data

LIST OF ABBREVIATIONS

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CHAPTER 1

INTRODUCTION

1.1 Introduction

We see that when a group or society is formed the some rules and laws are made by the people, for the people and to the people. The purpose of these rules and laws are to give a peaceful life to all who are living in that society. Whenever any law is violated by any one we say that crime is committed and who break that law is called criminal. To have peaceful life we need a well- organized law enforcement system. In our Somalia, we have very good facilities in law enforcement sector. But, due to less of facilities some works cannot be done in a very good way.

1.2 Motivation

In modern days crime is increasing day by day. To combat such crimes and to provide safety to citizens, police department plays a vital role. It always is a vital responsibility arresting criminal who is threat for the safety of society. After registering the FIR from any citizen, police starts investigation from them, after getting all the proofs against the criminal, It is the duty of the police to present all the proofs honestly to the court so that the right man can get right punishment. The true and right information provided by the people to police helps a lot in arresting the criminals who try to spoil the peaceful environment of society. Along with low salary scale, facilities of modern technology such as computerized system of keeping records are not provided to police department which cause low efficiency. As it is the age of computers, all the organization today use computers to maintain their records, so this facility should be given to police department. In order to increase their efficiency and to save their time, in our project we are going to implement a CRMS (criminal record management system). This is an online web application with database system in which police will keep the record of criminals who have been arrested. This will help the police department to manage their records easily.

1.3 Aims and Objectives

The objective of this system can broadly be listed as follows:

- To keep record of the criminals
- To record improvement and decline the rules and regulation activities of the Country.
- To keep record of criminals details for future investigation
- To keep record of criminal’s crime activities
- Reduce manual and redundant records keeping
- Facilitate interaction and sharing of information among police departments, districts, state/headquarters and other police agencies
- Building security and monitoring control to ensure only authorized personal have access to the criminal information

1.4 Project Organization

Chapter 2: In this chapter we have discussed the web based application and history of web based criminal record application as well as some previous works using reference.

Chapter 3: In this chapter we have discussed the steps of system development life cycle (SDLC)

and methodology used to develop the system using various figure.

Chapter 4: In this chapter we have described the requirement engineering process, software requirement for development, and how to analyze the system through Use Case, Block Diagram and Flowchart

Chapter 5: In this chapter we have described the design process of the system using System Context Diagram (SCD), Data flow diagram (DFD), Entity Relationship Diagram (ERD) and Activity Diagram

Chapter 6: This chapter we have described how implemented the system and explained interface designing steps with various screen shots.

Chapter 7: In this chapter we have illustrated the software testing types, validation and testing methods used this system along with a table showing different test results.

Chapter 8: In this chapter we have explained the application area of the system and where the system can be used

Chapter 9: In this chapter we have presented the result and discussion of the system by showing all necessary screen shots of the application.

Chapter 10: In this chapter we have discussed the conclusion, limitation, and future working

Scope on the system.

1.5 Summary

In this chapter, we have discussed the aims and objectives of the project, situation of the current system, necessity and brief overview of the proposed system.

CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

We see that when a group or society is formed, some rules and laws are made by to follow. The purpose of these rules and laws are to give a peaceful life to all who are living in that society. Whenever any law is violated by anyone we say that crime is committed and who break that law is called criminal. To have peaceful life we need a well-organized law enforcement system. In our Somalia, we have very good facilities in law enforcement sector. But, due to less of facilities some works cannot be done in a very good way.

2.2 Background

The project is aimed to develop a crime file for maintain a computerized records of all the fir against crime. The system is desktop application that can be access throughout the police department. This system can be used as application for the crime file of the police department to manage the records of different activity related to first information report. In suck desktop crime file system we will manage all such activities (like registration of the criminal, updating information, search of particular viewing of the respective reports of crimes) that will save time, manpower. This system will provide better prospective for the enhancement of organization regarding to quality and transparency.

2.3 Some Related Works

Prakruthi Prakasha, et.al [1]. In this research work, the web-based criminal record system (CRS) aims to use mobile devices in place of traditional GPS devices in order to facilitate the police to record the location of the committed crime. Despite from the location-based service, the CRS offers the police to describe the detail and simultaneously attach the images or multimedia files. The online crime reporting system has been developed to override the problems prevailing in the practicing manual system. This software is supported to eliminate in some cases reducing the hardships faced by the existing system.

Murat Dağlar, et.al [2]. As essential apparatus in crime analysis, crime mapping and Geographical Information Systems (GIS) are being progressively more accepted by police agencies. Development in technology and the accessibility of geographic data sources make it feasible for police departments to use GIS and crime mapping. GIS and crime mapping can be utilized as devices to discover reasons contributing to crime, and hence let law enforcement agencies proactively take action against the crime problems before they become challenging. The purpose of this study is to conduct a literature review of Geographical Information System and Crime Mapping in Crime Analysis and to propose policy recommendations regarding to implementation of crime mapping and GIS.

Prof. V. V. Bhujade, et.al [3]. This feature is made available to public for interaction with police indirectly. This system registers the complaints from people throughonline and is helpful to the police department in identifying criminals. In this system any person can register their complaint online.The aim ofthis project is to develop an E-cops reporting and management system which is easily accessible to the public, police department and theadministrative department.Generally many crimes seen by the public will not reach to the police due to many reasons like fear, lack of time, ignorance. Due to thisreason many cases are not even reported to the police station. Though some cases are registered they are not investigated properly due to lack ofevidences and cooperation of the public.

Sahar Bayoumi, et.al [4]. Geographic or cartographic Visualization is a form of information visualization includes principles of cartography, geographic information systems (GIS) and Exploratory Data analysis (EDA). Throughout this work, we will introduce related works in the field of crimes which we classified based on either spatial or spatial and temporal aspects. Crimes remain a social problem of grave concern where police departments have to suppress and detect crimes R. Subhashini et.al [5]. Geographical Information System (GIS) is one of the aiding domains of technology where a number of applications are being deployed to assist people in understanding and visualizing data rather than having it in other complex forms. Implementing one of such kinds of technology for crime analysis will help people in knowing the crime rate of their place in comparison to other places and will also provide hand-in-hand support to the police for providing additional focus on those regions. Crimes are the concerning factors of every country for its political, economical and social development. Yet, the number of technologies available in detecting and reporting crimes are limited. A Geographical Information System (GIS) based application can be implemented that can be used and accessed by everyone to file the crimes happening in their locality and to know about other crimes.

2.4 Summary

In this chapter, we have discussed some topic related with desktop application and the preview related works of development.

CHAPTER 3

METHODOLOGY

3.1 Introduction

Methodology is the theoretical and systematic analysis of strategies related to a field of study. It includes the theoretical analysis of the collection of strategies and guidelines related to apart of the knowledge A methodology does not set out to provide solutions—it is therefore, not the same as a method. Instead, a methodology offers the theoretical underpinning for understanding which method, set of methods, or best practices can be applied to a specific case, for example, to calculate a specific result.

3.2 Methodology

A software development methodology or system development methodology in software engineering is a framework that is used to structure, plan and control the process of development information system.

There are many of methodology in my project it does not strictly follow a single methodology. It has been development by considering waterfall methodology.

3.3 Software Development Life Cycle (SDLC)

The cycle of the software development gives us an overview and guidelines for the development of quality software. For our project, we follow SDLC to make reliable for the user [6].

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Fig 3.1 Software Development Life Cycle

3.3.1 Feasibility Study

The feasibility study is an evaluation of the potential of a proposed project which is based on extensive and research to support the process of decision making [6].

Objective of feasibility study:

- Technology and system feasibility
- Legal feasibility
- Operational feasibility
- Schedule feasibility

3.3.2 Requirement Definition

A requirement is a physical and functional need that a particular design, product or process must be able to perform. It is commonly used in a formal sense in system engineering, software engineering and enterprise engineering [6].

Requirement Definition involves three major frames are:

- Requirement Analysis
- Requirement Specification
- Requirement Validation

3.3.3 System Analysis

System analysis is the process of collecting a factual data, understand the process involved, identifying problem and recommending feasible suggestion for improving the system functioning, this involving studying the business process, gathering operational data, understand the information flow, finding out bottlenecks and evolving solution for overcoming the weakness of the system so as to achieve the organization goals. System analysis also includes subdividing of complex process involving the entire system, identification of data store and manual process [6].

This major objectives of system analysis are to find answers for each business process:

- What is being done?
- How is it being done?
- Who is doing it?
- When is he doing it? Why is it being done?
- How can it be improved?

3.3.4 System Design

The design phase is the architectural phase of system design. The flow of data processing is developed into charts, and the project team determines the most logical design and structure for data flow and storage. For user interface, the project team designs mock-up screen layouts that developers use to write the code for the actual interface [6].

3.3.5 Coding

In the SDLC model, the design and coding of the program involves only 10% of the project’s commitment, here we compose the coding using a well-understood programming language like PHP, HTML, CSS3, BOOTSRAP, JAVASCRIPT, JQUERY, and MYSQL [6].

3.3.6 Testing

Testing involves executing and implementation of the software with test data and examining the outputs of the software and its operational behavior to check that is performing as required testing can be implementation in two ways [6].

- White box testing
- Black box testing

3.3.7 Implementation

The installation and acceptance stage is the final stage of SDLC. In this stage, the software is installed in the client place and the users are trained in using the new software.

- Inputs for installation and acceptance stage: the inputs of installation and acceptance stages are:
- Outputs of installation and acceptance stage: the outputs of installation and acceptance stages are:

- Production software – the software is installed in client machine with production data loaded into it.
- Completed acceptance test – the software is tested by the users in the client side and the acceptance test is completed.
- Customer acceptance memorandum – customer signs off the acceptance memorandum which means the project completion is smooth and client has accepted it.
- Archived software artifacts – the source code of the entire software and other software artifacts are archived for future use. Archived project plan the latest project plan is archived for future use [7].

3.4 Waterfall Model Application

The waterfall model was first process model to be introduced, it also referred to as a linear Sequential life cycle model. It is very simple to understand and use. In waterfall model, each phase must be completed before the next phase can begin and there is no overlapping in the phases Waterfall model is the earliest SDLC approach that was used for software development.

The waterfall model illustrates the software development process in a linear sequential flow, Hence it is also referred to as a linear-sequential life cycle model [8].

3.5 Waterfall Model Application

Every software development is different and required a suitable SDLC approach to be followed based on the internal and external factors. Some situations where the use of waterfall model is most appropriate are:

-Requirement are very well documented, clear and fixed.
-Product definition is stable
-Technology is understood and is not dynamic
-There are no ambiguous requirements.
-Ample resources with required expertise are available to support the product.
-The project is short.

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Fig 3.2 Waterfall Software Development Methodology

The above figure shows step by step of my application development process in different time period using waterfall methodology [8].

3.6 Summary

In this chapter, we have discussed about the background, methodology, and development process and project plan of the project.

CHAPTER 4

ANALYSIS

4.1 Introduction

The software requirement are description of features and functionalities of the target system. Requirement convey the exception of users from the software product. The requirement can be obvious or hidden, know or unknown, expected or unexpected from client’s point of view.

4.2 Requirement Engineering

The process to gather the software requirement form client, analyze and document them is known as requirement engineering. The goal of requirement engineering is to develop and maintain sophisticated and descriptive system requirement specification document.

4.3 Requirement Engineering Process

The main objective of the process are to describe the principle requirement engineering activities and the relationship, it depends on the application domain the people involved and the organization developing the requirements [9].

It is four steps process, which includes –

- Feasibility Study
- Requirement Gathering
- Software Requirement Specification
- Software Requirement Validation

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Figure 4.1 Requirement Engineering Process Model

4.3.1 Feasibility Study

A feasibility Study aims to reveal in an objective and rational way the strength and weaknesses of a current or proposed company, the opportunities and threats present in the environment, the necessary assets to be implemented and, ultimately, the prospective for success. A feasibility study is a study that incorporates software analysis in case it is economically advantageous, In case it can satisfy the technical requirement and if it is adoptable in the required environment. It also condition the basic work and decides whether to accept the project. Finally, the final result will be a hard plan to continue with the project.

A feasibility study assesses the potential for progress of the project, therefore, objectively perceived is an imperative factor in the validity of the study for potential investors and lenders [9].

4.3.2 Requirement Gathering

If the feasibility report is positive towards undertaking the project, next phase starts with gathering requirement from the user, analysis and engineering communicate with the client and end-uses to know their ideas on that the software should provide and which features they want the software to include [9].

4.3.3 Software Requirement Specification

SRS is a document created by system analyst after the requirement are collected various stakeholders. SRS defines how the intended software will interact with hardware, external interface, speed of operation, response time of system, portability of software across various platforms, maintainability, speed of recovery after crashing, security, quality, limitations etc. the requirements received from client are written in natural language, it is the responsibility of system analyst to document the requirement in technical language. It is the responsibility of system analyst to document the requirements in technical language so that they can be comprehended and useful by the software development team [9].

SRS should come up with the following features:

- User requirement are expressed in natural language.
- Technical requirement are expressed in structured language, which is used inside the organization.
- Design description should be written in Pseudo code.
- Format of forms and GUI screen prints.
- Conditional and mathematical notations for DFDs etc.

4.3.4 Software Requirement Validation

After requirement specification are developed, the requirement mentioned in this document are validated. User might ask for illegal, impractical solution or expected may interpret the requirements correctly. This results in huge increase in cost if not nipped in the bud [9].

Requirements can be checked against following conditions –

- If they can be practically implemented
- If they are valid and as per functionality and domain of software
- If there are any ambiguous
- If they are complete
- If they can be demonstrated

4.4 Software Requirement for Development

- Requirement for software

- PHP
- HTML
- CSS
- BOOTSRAP

4.5 Hardware Requirements for Use

- Keyboard
- Mouse
- Screen solution of at least 1024*768 required for proper and complete viewing of screen
- RAM 1GB
- Hard Disk 250 GB

4.6 Software Requirement for use

- Operating system- Desktop and laptop based OS
- Server XAMPP Control v3.3.2
- Application software PHP, MYSQL, Java script, Web browser like chrome.

4.7 Use Case

A use case is a software and system engineering term that describes how a user system to accomplish a particular goal. A use case acts a software modeling technique that defines the features to be implemented and the resolution of any errors that may be encountered.

The three main elements of use case are:

Actors: actors are the type of users that interact with the system.

System: Use case capture functional requirement that specify the intended behavior of the system. Goals: Use case is typically initiated by a user a fulfill goals describing the activities and variants involved in attaining the goal [10].

4.7.1 Characteristics associated with use case are

1. Organizing functional requirements
2. Modeling the goals of system user interaction
3. Recording scenarios from tiger events to ultimate goals
4. Describing the basic course of actions and exceptional flow of events
5. Permitting a user to access the functionality of another event

4.7.2 The steps in designing use case are

- Identify the user of the system.
- For each category of users, create a user profile. This includes all roles played by the users relevant to the system.
- Identify significant goals associated with each role to support the system. The system’s value proposition identifies the significant role.
- Create use case for every goal associated with case template and maintain the same abstraction level throughout the use case. Higher level use case steps are treated as goals for the lower level.
- Structure the use cases
- Reviewed and validate the users [10].

4.8 Use Case Diagram

Use case diagram are valuable for visualizing the functional requirements of system that will translate into design choices and development priorities.

Use case diagrams are valuable UML diagram type and frequently used to analyze various system. They enable you to visualize the different types of roles in a system and how those roles interact with the system [10].

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Fig 4.2 Use Case Diagram for CRMSS

The above figure shows the use case diagram for Criminal record management system where the admin and sub-admin can use the software for adding criminal, viewing criminal list, adding crime report, viewing crime report and creating accounts, on the other part police can also add criminals and crime reports, viewing criminals lists and crime reports, where the court can use the software for giving punishments to the criminals.

4.9 Block Diagram

A block diagram is a diagram of system in which the principle parts of functions are represented by block connected by lines that show the relationships of the blocks. They are heavily used in engineering in hardware design, electronic design, software design, and process flow diagrams.

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Fig 4.3 Block Diagram of CRMSS

The figure above shows different function of admin, sub-admin, police, and court in block of Criminal record management system.

4.10 Flowchart

4.10.1 Definition

A flowchart is formalized graphic representation of logic sequence, work or manufacturing process, organization chart or similar formalized structure. The purpose of a flowchart is to provide with a common language or reference point when dealing with a project or process [11].

4.10.2 Necessity to use a Flowchart

- To develop understanding of how a process is done
- To study a process for improvement
- To communicate to others how a process is done
- When better communication is needed between people involved with the same process
- To document a process
- When planning a project [11].

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Fig 4.4 flowchart for CRMSS

The above figures shows the application process flow using symbol, where any user can login into System if he has no account then the admin or sub-admin can create an account to him/her. After creation of account user this system based on user type for their respective functionalities show in flow diagram.

4.11 Summary

In this chapter, we have discussed about the requirement analysis, requirement validation software and hardware requirement, use case diagram, block diagram and flowchart diagram.

5.1 Introduction

CHAPTER 5

SYSTEM DESIGN

System design is the process of defining the architecture, components, modules, interface, and data for a system to satisfy specified requirement. System design could be seen as the application of system theory to product development.

5.2 System Design

The phase of design process is given below:

- Architectural design: the design of system architecture which describes the structure behavior.
- Logical design: it’s an abstract representation of the data flows, inputs and outputs of the system, the requirements about the system are described.

- Input requirements
- Output requirements
- Storage requirements
- Processing requirements
- System control and backup or recovery

Another way the physical portion of system design can generally be broken down into three sub tasks:

- User interface design.
- Data design.
- Process design [6].

5. 3 System Context Diagram (SCD)

A system context diagram (SCD) in software engineering and systems engineering is a diagram that defines the boundary between the system, or part of a system, and its environment, showing the entities that interact with it, this diagram is a high level view of a system. It is similar to a block diagram [10].

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Fig 5.1 System context Diagram (SDC) of CRMSS

The above figure shows the high level view and interaction of Criminal record management system.

5.4 Data Flow Diagram

5.4.1 Data Flow Diagram

Data flow diagram is graphical representation of flow data in an information system. It is capable of depicting incoming data flow, outgoing data flow and stored data. The DFD does not mention anything about how data flows through the system.

There is a prominent difference between DFD and flowchart, the flowchart depicts flow of control in program modules. DFD’s depict flow of data in the system at various levels. DFD does not contain any control or branch elements [6].

5.4.2 Types of DFD

Data flow Diagram are either logical or physical.

- Logical DFD – this type of DFD concentrates on the system process and flow of data in the system.
- Physical DFD – this type of DFD shows how data flow is actually implemented in the system. It is more specific and close to the implementation.

5.4.3 DFD Components

DFD can represent source, destination, storage and flow of data using the following set of components-

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- Entities – entities are source and destination of information data. Entities are represented by rectangular with their respective names.
- Process – activities and action taken on the data are represented by circle or round edged rectangles.
- Data storage – there are two variants of data storage- it can either be represented as a rectangle with absence of both smaller sides or as an open-sided rectangle with only one side missing.
- Data flow – movement of data is shown by pointed arrows. Data movement is shown the base of arrow as its source towards head of the arrow as destination [6].

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