An E cient Scheme for Secure Message Transmission using Proxy Signcryption

Previous proxy signature schemes enable a principal to have a trusted proxy agent sign messages on its behalf We present a proxy signature scheme that combines the functionality of proxy signing and en cryption This proxy signcryption scheme is useful for applications that are based on unreliable datagram style network communication model where messages are individually signed and not serially linked via a ses sion key to provide authenticity and integrity Use of a proxy agent to perform signature function is desirable for applications that are expected to support computing devices with low computational power and storage capacities Integration of encryption functionality to provide secrecy at no additional cost to the proxy signature generation is an e cient means by which to support the class of applications targeted by this research work such as e commerce using mobile computing and communication