Yasmine Abouelseoud

Learn More
Signcryption is a public key cryptographic primitive that combines the functionalities of encryption and digital signatures in a single logical step at low computational and communications costs. This paper presents a new efficient multi-recipient identity-based signcryption scheme. The scheme provides public verifiability of ciphertext origin which is an(More)
The certificate-based cryptosystems is traditional way in providing the system parameters. Identity-based cryptography is more efficient than certificate-based cryptosystems. Each user in identity-based cryptography uses any arbitrary string that uniquely identifies him as his public key. This paper proposes a new identity-based tripartite signcryption(More)
Anonymity of consumers is an essential functionality that should be supported in any digital rights management system. Privacy protection is an important aspect for wider acceptance of consumers of DRM systems. The concept of a blind signature is one possible cryptographic solution, yet it has not received much attention in the identity-based setting. In(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)
Authentication and confidentiality are the most important security goals to be achieved. This paper proposes a new tripartite signcryption scheme without bilinear pairings. The proposed tripartite signcryption scheme is efficient when three entities want to perform secure transactions as in mobile communication or in e-commerce. The proposed scheme is based(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, 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)
In this paper, the problem of establishing a shared session key in an authenticated way is addressed. New key agreement protocols that support explicit authentication are proposed. The protocols are designed in such a way that permits a trusted third party, such as a firewall, to verify the identities of the parties involved in a key agreement session. This(More)