Sms Encryption Using Rsa Algorithm

Description

ABSTRACT

The rapid development of communication technology, on the one hand, is bringing many technological conveniences with it and simplifying our lives. On the other hand, it has disadvantages on hiding the information that is continuously roaming through various communication media resources between senders and receivers and on not sharing them with third people.

The aim of eliminating these disadvantages via specific security methods and algorithms is related to the discipline called cryptography, which includes information security.

In this study, how RSA encryption algorithm and the secure messaging process on the SMS channel are realized in the devices with the Android operating system is examined thanks to the developed application. The advantages and the disadvantages of the application are demonstrated. The solution proposals are presented.

The application is tested with different key sizes for fast and powerful messaging. The different key sizes which can be used for key generation processes and changes occurring on encrypted messages are mentioned. Also, existing alternative solutions to be used for the encryption process in secure messaging are stated.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

1.0      INTRODUCTION

• BACKGROUND OF THE PROJECT
• PROBLEM STATEMENT
• AIMS AND OBJECTIVES
• SIGNIFICANCE OF THE PROJECT
• SCOPE OF THE PROJECT
• DEFINITION OF TERMS

CHAPTER TWO

2.0          LITERATURE REVIEW

• REVIEW OF THE STUDY
• OVERVIEW OF RSA (CRYPTOSYSTEM)
• HISTORY RSA (CRYPTOSYSTEM)
• RSA ALGORITHM
• RELATED WORK

CHAPTER THREE

3.0          METHODOLOGY

• PROPOSED SYSTEM
• IMPLEMENTATION

CHAPTER FOUR

• PERFORMANCE EVALUATION

CHAPTER FIVE

• CONCLUSION
• REFERENCES

CHAPTER ONE

1.0                                                            INTRODUCTION

1.1                                               BACKGROUND OF THE STUDY

Security issues have an important place in today’s communication technologies. Since mutual communication must be done through secure channels that don’t allow third people to intervene, it is very important to make the security levels of these channels as high as possible.

Mutual communication is provided by talking, messaging and so on, and during the communication process that is realized via these ways, various security methods can be implemented by the service provider firms or software companies without making users aware of them. Of all security methods, the encryption algorithms have a great importance. These algorithms are ranked according to their complexity and resist by the rate of their complexity and power from the moment seized by third people who can penetrate mutual communication.

As a result of the rapid developments in mobile communications, SMS messaging is widely used in both the business world and the social environments.

People can share their private information which are related to their social relationships or works easily and quickly with a total of 1120 bits if each character of SMS which is up to 160 character

• is created by 7 bits [1]. If you pay attention to the architecture of the SMS messaging method in Fig 1, it is seen that SMS is never delivered directly from sender to receiver [2].

Figure 1.  SMS architecture

Firstly, sent SMS passes from the mobile switching center that performs the message routing process. Then it is stored in the SMS center and directed for the transmission process [3]. Messages are transmitted as clear text between mobile switching stations and SMS centers. Namely, they aren’t subject to any encryption or hiding processes during transmission. This case causes a number of disadvantages.

These disadvantages can be listed as follows;

1. Before reaching the receiver from the sender, message contents are stored in the operator’s system as clear
2. Message contents can be read by the operator

• It is unclear that how reliable the operator system which stores message contents is against external

When message contents are requested by the courts from the related operators if it is necessary, they can easily be brought out. Encryption algorithms can be utilized to remove such cases and to provide secure messaging environment. Thus, messages will circulate as encrypted form in transmission medium, not as clear text. Somebody who has seized encrypted data does not obtain original message from the encrypted data unless they possess the necessary method or a key. Encryption methods are divided into the following categories: private key cryptography and public key cryptography.

In a symmetric key algorithm, the sender and receiver must have a shared key set up in advance and keep secret from all other parties; the sender uses this key for encryption, and the receiver uses the same key for decryption. In this case, except for transmitted encrypted message, encryption key must also be submitted confidentially, which is one of the disadvantages of private-key cryptography [4].

If a third person who has managed to enter the system operator or listen to transmission medium seizes the key value, s/he can turn the encrypted data into original data. The most important feature of public key cryptography which is another method is that the key value used to encrypt the message is different from the key value used to decrypt the message. Each user has two keys in this method: public key and private key. The public key of the user can be viewed by anyone. The private key is kept secret by the user. When someone wants to send a message to user, they use the user’s public key and create the encrypted message and then send the encrypted data to user. The user decrypts the encrypted data with her/his private key and obtains a meaningful message.

The data which has been encrypted by the user’s public key is only solved with the user’s private key [4]. When the user wants to send a message, s/he reaches the public key library. S/he takes the public key of somebody to which s/he wants to send a message and encrypts the message and then s/he sends the encrypted message to the receiver. The only thing that the receiver must do is to solve the message with his/her own private key.

RSA algorithm, which is one of the public-key encryption methods and more reliable than the private key encryption algorithms, is used in this study for secure messaging via SMS.

1.2                                                     PROBLEM STATEMENT

Communication has been a major factor in human’s everyday life. The advancement of information technology changed the method of online transactions. No one uses SMSs that frequently to pass messages from one to another because of the arrival of the free data services and cheap data packs from the ISPs. But SMS still plays a very vital role in our day to day lives and its theft is increasing concerns to secure it. No airline or bank or subscription services send their transaction details through any web application but through SMS. SMS plays an important role in online transactions .With the increasing use of SMS for communication and information exchange, care should be taken when sensitive information is transmitted using SMS. Users should be aware that SMS messages might be subject to interception. Solutions such as encrypted SMS should be considered if there is a need to send sensitive information via SMS. The messages are encrypted by strong cryptographic algorithms. The encrypted message received by the customer decrypt the message by authentication. This is only known to user. This study uses RSA algorithm for secure keys to secure message. Authentication is implemented by using pattern lock. This system provide secure and reliable communication environment.

1.3                         AIM AND OBJECTIVES OF THE STUDY

This project is aimed at designing and implementing security software using cryptography method (process in which plain text is converted to cipher text (encrypted text) which uses a key that is known to both sender. It would be developed for individuals or organisations that need to secure their files and other document.

Specifically, the objectives of this project are stated as follows:

• To ensure that SMS is well secured or protected.
• To ensure data communication a client-to-client or server-to-client relationship on a network.
• Securities and confidentiality of personal document for clients or users on a network involved in SMS or transfer or sharing.
• To replace the traditional unsecured chatting and file transfer application with a more secured encryption enabled data communication application
• To ensure that illegal alterations to personal or confidential information is greatly reduced.

1.4                                SIGNIFICANCE OF THE STUDY

Some of the significance of this project research is explained below as data/files encryption is very essential in the life of an individual, ICT researchers, ICT companies and non – ICT companies. The various significance of this research work is explained below: The importance of the encryption techniques for large and growing sectors of the society is fundamental. The use of encryption is as important for the storage and use of information as it is for data and telecommunication. In order to secure the necessary legal, evidentiary function of digital information as we go away from the use of physical documents, strong cryptographic techniques are required. The importance of encryption in file transfer applications will increase substantially in the coming years in place with the growing traffic on publicly available networks, like the internet as they continue to increase in size; Files or documents are well protected on a network with the existence of Encryption algorithm embedded in the application. Private persons, companies, government agencies and other organisations use cryptography techniques in order to safely communicate with partners, customers, etc, but also in order to increase security in their own internal processes; to protect stored information, and communicate with employees who are geographically distributed or work from a distance. By using encryption for communication over open and publicly accessible networks, information/data can be transferred from the sender to receiver without unauthorized interpretation (data integrity).

1.5                                           SCOPE OF THE STUDY

The scope of this project is essentially centred on incorporating encryption algorithms into data communication which entails encryption enabled files transfer applications and generally securing SMS against illegal access or transfer or SMS sharing systems. This project is a security application program on a network or popularly referred to as security “socket programming”. It explores SMS encryption.

1.6                                             DEFINITION OF TERMS

1. Data: Information in raw form or unorganized form such as alphabets, numbers, or symbols that refer to or represent condition, ideas or object.
2. Database: A systematically organized or repository of indexed information usually a group of linked data files that allows easy retrieval, updating, analysis and output of a data usually stored in a computer.

• File: Is a collection of data stored in one unit, identified by a Filename. It can be a document, picture, audio or video stream, data library, application or other collection of data.

1. Encryption: Encryption is the process of translating plain text data (plaintext) into something that appears to be random and meaningless (cipher text). Decryption is the process of converting cipher text back to plaintext.
2. Plain-text: Plain-text is any text that is still in its readable format or that has been converted from cipher-text back to plain text as a result of Decryption.
3. Cipher-text: Cipher-text is the text which has been converted to the format that cannot be read as a result of encrypting the text.

• Firewall: Set of related networks located at a network gateway server that protects the resources of a private network from users from other networks.
• Cryptography: it is the act of writing in code or cipher.

1. Symmetric-key: The method of using a single key for encryption and decryption. It can also be referred to as private-key
2. Asymmetric-key: The method of using a key for encryption and another key for decryption. It can also be referred to as a public-key.
3. Algorithm: It is a step by step instruction of solving problem.

• SMS (short message service) is a text messaging service component of most telephone, Internet, and mobile device systems.
• Kernel: A kernel is the piece or pieces of pieces of software that is responsible for servicing resource request from the application and the management of resources. A kernel grant access to resources such as allocating space for a new file or creating a network collection.
• Cryptography API: Contains functions that allows applications to encrypt or digitally signed sign data in a flexible manner, while providing protection for the user’s sensitive private key data.

1. Stream Cipher: Stream ciphers, which encrypt continuous streams of data.

• Block Cipher: Block ciphers, which encrypt block of data of fixed size.