Design And Implementation Of Steganography Communication System

With the development of the Internet,the way people send and receive messages has changed from the old way of texting or calling to instant messaging software communication or social networking site status sharing.The amount of information has exploded with the maturity of computer technology and people’s daily needs,but more and more serious problems of information security come.Information transmission in the Internet public channel without any confidentiality measures will have the risk of leakage,which poses a great threat to personal privacy,company secrets,and even social and national security.Information security has attracted higher and higher attention.Generally speaking,encryption is a solution for information security.It points that the information or communication channel will be encrypted to achieve its content from unauthorized browsing.However,in some application environments,the fact of protecting confidential communication or storage is very important,encryption does not have the act of confidential communication concealment.Steganography is a class of information hiding technology,which hides confidential information in publicly available data content for transmission or storage,so that non-authorized persons not only cannot view the confidential content,but also have difficulty in knowing the existence of confidential communication or confidential stored facts.Authorized recipients can only extract the hidden message from the steganography-containing carrier after steganography.In this thesis,I study data steganography based on the compression and encoding process of the picture and video carriers.I design adaptive data steganography algorithms for different compression methods and features,so that sensitive data can be written selectively according to the content of the carrier.Only the authorized party can decrypt the sensitive information to achieve the purpose of hiding the encryption behavior.Based on the design and implementation of the steganography algorithm,an instant messaging system is designed and implemented to provide transmission channels for both ordinary messages and cryptographic messages.The research mainly includes the following aspects.This thesis analyzes the requirements of the system from the perspective of data steganography in combination with existing instant messaging software in the market.In the functional requirements analysis,the system is divided into four modules,namely,user management module,list management module,data steganography module,and instant messaging module.In the non-functional requirements,the security requirements are first put forward for the steganography algorithm,and then in the non-functional requirements,the security requirements for the steganography algorithm and the performance of the instant messaging system are proposed to support normal services under high concurrency scenarios.The technology selection and architecture design of the system based on the requirement analysis,which describes in detail the operation principle of the system under the architecture and the solution of the high concurrency problem.Then,the transmission protocol and reliability guarantee scheme of the system is designed to determine the overall structure of the system.The functional modules and database of the system are designed,which describes in detail the operation process of the system and the data storage method.Based on the design,I implemented the system.The specific details of the system building process and main function implementation are shown.Finally,the system is tested.The functional test verifies that the system functions properly and meets the requirements,and the non-functional test verifies the security of the steganographic algorithm and the reliability of the system.