Protection System Design Software Resources

In recent years, people had high regard for software protection more and more. For software developers, they should take the technology to protect their intellectual property rights. It is software encryption technology. Traditional software dog works through the additional circuit under Parallel Interface, but Parallel Interface limits the further development of traditional software technologies dogs because of its characteristics. At the same time, most of the software dog in the market at the present have shortcomings that are not high intensity.In this article, the writer has researched the predecessor's research results and analyzed the commercial encryption dog in the present markets. Based on own development practice, I elaborated the related content about the software encryption dog which developed by successfully integrate USB interface technology and the software dog technology .It has high encryption intensity convenience and the stronger compatibility. In the course of the research it has been discovered that if the USB software encryption dog communicates with the PC host by using the DES algorithm encryption, and unifying to the measure such as product sequence number and installs number of times and so on, it can constitute the high strength encryption system, thus to resists effectively cracker. Moreover, in order to be advantageous for the software developer to use encryption dog, this scheme has also provided the outer covering tool.In the first chapter of this article the writer has narrate some knowledge about the software protection technology and the software dog. The second chapter in this article has made the simple elaboration to the cryptology concept and the principle. It has provided the theory guarantee about how the date transmission work secretly between the software encryption dog and the host that analysising the crypto-algorithm . In third chapter the writer has analyzed USB bus standard and technical characteristic and introduced the structure and technical parameters of the chip PDIUSBD12 that can control USB interface as todesign USB software encryption dog. The fourth chapter in the this article has studied and expounded the high strength software encipherment scheme that based on the USB interface and proposed a realization method for software encryption dog that has creativeness and high strength .The writer also proposed some method to pretect the software encryption dog from decryption. In the fifth chapter the writer has in detail narrated the USB software encryption dog hardware design and realization , Meanwhile he took the firmware in mono-computer integrated into a circuit as the hardware the important constituent, he discussed the firmware function, and described its realization process. Sixth chapter is the most important in this paper. Due to the software different function the high software include several modules: The encryption algorithm realization, the USB host driver design and the interface program for application.Finally, the writer has made the summary to the full text and propose the further thinking that aimed at this system the question which existed in the secure aspect.