Yasmine Abouelseoud

Learn More
In this paper, a new identity-based proxy signcryption scheme is presented. The proposed scheme allows partial delegation of signing rights. Consequently, a signature created by the proxy signer is distinguishable from that created by the principal signer. This level of security is a common requirement in many applications to prevent malicious proxy agents(More)
Signcryption is a cryptographic primitive which simultaneously provides both confidentiality and authenticity in a single logical step. In a proxy signature scheme, an original signer delegates his signing power to a proxy agent, who signs a message on behalf of him. This paper introduces a new proxy signcryption scheme based on the Discrete Logarithm(More)
Signcryption is a cryptographic primitive which simultaneously provides both confidentiality and authenticity in a single logical step. Signcryption based on elliptic curves provides the same level of security using smaller keys compared to schemes based on the discrete logarithm problem over finite fields. Identity-based cryptography serves as an efficient(More)
— In this paper, new authenticated key agreement (AKA) protocols are proposed to be used by two entities and three entities in order to establish a common session key between these entities. This key is used later to encrypt the data exchanged between the entities to assure confidentiality over public insecure channels. Authenticated key agreement protocols(More)
In this paper, a new blind identity-based signature scheme with message recovery based on bilinear pairings on elliptic curves is presented. The work is motivated by the importance of blind signatures as a cryptographic primitive essential in protocols that guarantee anonymity of users. This is particularly of interest in DRM systems, electronic cash(More)
This paper presents a new approach for secure hiding of textual data in a colored digital image. Use of images as a cover media in steganography is based on the deficiencies in the human visual system (HVS). The proposed technique employs two independent chaotic sequences for specifying the locations where the message bits are embedded in the cover image(More)