Sharif Digital Repository

Security protocols may be provable secure when used alone, but these protocols lose their security under composition operation. Universal Composition framework (UC) is a tool for analyzing security protocols under composition. UC framework guarantees that the cryptographic protocols keep their security under this composition operation. In this paper we state a modeling for key-evolving signature protocol within the UC framework as a case study. To do this, the ideal functionality is proposed for key-evolving signature scheme that keeps the security requirements of this scheme. Finally, we show that UC definition of security is equivalent to definition of security which is termed here as...