An Efficient Software Protection Scheme

Software piracy has been considered one of the biggest problems of this industry since computers became popular. Solutions for this problem based in tamperproof hardware tokens have been introduced in the literature. All these solutions depend on two premises: (a) the physical security of the tamperproof device and (b) the difficulty to analyze and modify the software in order to bypass the check of the presence of the token. The experience demonstrates that the first premise is reasonable (and inevitable). The second one, however, is not realistic because the analysis of the executable code is always possible. Moreover, the techniques used to obstruct the analysis are not helpful to discourage an attacker with usual resources. This paper presents a robust software protection scheme based in the use of smart cards and cryptographic techniques. The security of this new scheme is only dependent on the first premise because code analysis and modification are not useful to break this