一种虚拟仪器软件的加密方法

为了保护虚拟仪器的软件不被侵权，针对基于便携式PC(Personal Computer)的虚拟仪器软件易于被复制的问题，分析了几种硬件加密方法的特点和效果，提出了采用以复杂可编程逻辑器件芯片为核心来设计加密卡，把硬件和软件结合起来进行加密的方法，并付诸实施。因此，减少了硬件故障率，节省了印制电路板的面积，降低了加密成本，通过灵活选择加密算法，并配置到加密卡芯片的办法，造成各加密卡在内部算法上不完全相同，因此增加了破解的难度，提高了对虚拟仪器软件的保护性。

Method to Encrypt the Virtual Instrument Software

The software in virtual instrument (VI) based on portable personal computer (PC) can be easily copied.The characteristics and effect of several encryption methods are analyzed in this paper to protect the property of software not to be infringed. The method that hardware and software are combined in an encrypting card is put forward and put in practice. The complex programmable logic device (CPLD) chip is used as the core of the encryption card, with low probability of hardware fault, area saving of printed circuit block (PCB) and reduced cost of encryption. The difficulty of piracy is enhanced and the VI software is effectively protected with the encryption arithmetic chosen flexibly and configured in the chip on the encryption card, because the arithmetics in the chips are different from each other.