The efficient proxy-protected proxy-signcryption scheme based on the ECKCDSA for mobile environment

C. Gamage et al. proposed a "proxy-signcryption scheme" that combines proxy signatures proposed by M. Mambo and a signcryption scheme proposed by Y. Zheng. However, their scheme has some disadvantages that proxy agent cannot be protected because the original signer can create a valid proxy-signcryption instead of proxy agent and an additional revocation protocol is needed if original signer wants to change the proxy agent. To solve these problems, we propose an improved proxy-signcryption scheme based on a proxy-protected proxy signature for partial delegation with warrant introduced by S.J. Kim and ECKCDSA(Elliptic Curve Korea Certificated based Digital Signature Algorithm). Our proposed scheme can protect proxy agent and no additional computation is needed when a proxy right is change and is efficiency because of using ECKCSA in the view of computation complexity.