Computer Interface Encryption System Design And Development

The popularity of computer technology, to make the information as an important resource in today’s society, which determines the security of computer information of great practical significance and far-reaching historical significance. The widespread use of computers has brought extensive use of mobile storage media, a lot of sensitive data is stored in the mobile carrier, and the resulting data on removable storage carrier security requirements also increased.Based on this, the paper design and implementation of a computer interface based on USB1.1 protocol encryption system, connected to the computer through the USB interface, the system satisfy the commonly used USB drive in the realization of sensitive data encryption needs. First, the use of PROTEL 99 hardware circuit design, system hardware is mainly used STC11F32 XE microcontroller as the processing core, Philips PDIUSBD12 as uplink transmission control chip, CH375 as a downlink control chip, using the SD card key management. Software design, control procedures through the preparation of keil, software design including the DES algorithm for data encryption, hardware-driven Mass-Stroage protocol processing, SPI bus, a way to read and write SD memory key data, encrypted files hidden, U disk of scattered areas of reading and writing data to achieve the USB firmware in the preparation of several parts.System to complete a printed circuit hardware, installation and commissioning, on this basis, the write control program to the processor, the system of functional verification and performance testing. Through the scientific method, the system stability, speed and function indicators for testing, come to a good system to meet the design requirements, the functional indicators to achieve the desired design. At the same time, the system to better achieve the appearance of small, easy to use for a wide range of cryptographic strength of the design requirements. On this basis, further development of the system and made the expected improvement. As users of mobile carriers in the sensitive data stored in the security needs of more and more, I believe computer interface encryption system will have a wider market.