Design Of Information Transmission Platform Based On Embedded System

With the continuous development of network technologies and information infrastructure, computer network becomes a very important and convenient method to transmit information to other people. But because of the opening form, the data transmitted through the network are easily stolen, distorted or fabricated by illegal person. The embedded system has the advantage of small, cheap and low power and will be suitable for different application requirement. A secure information transmission platform based on embedded system is designed in this thesis. The embedded system is taken as a node server to protect the information, protecting file data by encryption and picture by digital watermarking. The system will solve the reality, safety and integrality of online exchange very well.The system is designed on HHARM9200 embedded developing platform and embedded Linux operating system. The system adopts different transmission method to improve the transmission efficiency with a view to different transmission characteristic of file data and picture data. It adopts the method of capturing data packets for file data, and storing, sending for picture data. A secure authentication and key exchange protocol is designed in this thesis, which could prevent Man-In-The-Middle attack, increasing the reliability of authentication and security of key exchange. The data encryption module is implemented by OpenSSL including symmetry key algorithm, public key algorithm, Hash function.The system's function is tested finally, the data transmission rate using different encryption algorithm. The security of the system is analyzed from the view of security of network transmission and cryptography. The result shows that the security platform can rapidly and stably guarantee not only the file data's sender identity, confidentiality and integrity, but also speech data's identification and temper verification.