Cryptanalysis of an Efficient Signcryption Scheme with Forward Secrecy Based on Elliptic Curve

The signcryption is a relatively new cryptographic technique that is supposed to fulfill the functionalities of encryption and digital signature in a single logical step. Several signcryption schemes are proposed throughout the years, each of them having its own problems and limitations. In this paper, the security of a recent signcryption scheme, i.e. Hwang et al.'s scheme is analyzed, and it is proved that it involves several security flaws and shortcomings. Several devastating attacks are also introduced to the mentioned scheme whereby it fails all the desired and essential security attributes of a signcryption scheme.Comment: 5 Pages, 2 Figure

LPKI - A Lightweight Public Key Infrastructure for the Mobile Environments

The non-repudiation as an essential requirement of many applications can be provided by the asymmetric key model. With the evolution of new applications such as mobile commerce, it is essential to provide secure and efficient solutions for the mobile environments. The traditional public key cryptography involves huge computational costs and is not so suitable for the resource-constrained platforms. The elliptic curve-based approaches as the newer solutions require certain considerations that are not taken into account in the traditional public key infrastructures. The main contribution of this paper is to introduce a Lightweight Public Key Infrastructure (LPKI) for the constrained platforms such as mobile phones. It takes advantages of elliptic curve cryptography and signcryption to decrease the computational costs and communication overheads, and adapting to the constraints. All the computational costs of required validations can be eliminated from end-entities by introduction of a validation authority to the introduced infrastructure and delegating validations to such a component. LPKI is so suitable for mobile environments and for applications such as mobile commerce where the security is the great concern.Comment: 6 Pages, 6 Figure

Remarks on combinatorial aspects of the KP Equation

Accepted for publication: AIP Conference Proceedings, 2nd International Workshop on Nonlinear and Modern Mathematical Physics, March 9-11, 2013. v2: Several clarifications made, references added, typos corrected; 16 pages, 1 figureAccepted for publication: AIP Conference Proceedings, 2nd International Workshop on Nonlinear and Modern Mathematical Physics, March 9-11, 2013. v2: Several clarifications made, references added, typos corrected; 16 pages, 1 figureAccepted for publication: AIP Conference Proceedings, 2nd International Workshop on Nonlinear and Modern Mathematical Physics, March 9-11, 2013. v2: Several clarifications made, references added, typos corrected; 16 pages, 1 figureAccepted for publication: AIP Conference Proceedings, 2nd International Workshop on Nonlinear and Modern Mathematical Physics, March 9-11, 2013. v2: Several clarifications made, references added, typos corrected; 16 pages, 1 figureNSF through grant DMS-0807705; AR is supported by the NSF under grant DMS-100438

SSMS - A Secure SMS Messaging Protocol for the M-payment Systems

The GSM network with the greatest worldwide number of users, succumbs to several security vulnerabilities. The short message service (SMS) is one of its superior and well-tried services with a global availability in the GSM networks. The main contribution of this paper is to introduce a new secure application layer protocol, called SSMS, to efficiently embed the desired security attributes in the SMS messages to be used as a secure bearer in the m-payment systems. SSMS efficiently embeds the confidentiality, integrity, authentication, and non-repudiation in the SMS messages. It provides an elliptic curve-based public key solution that uses public keys for the secret key establishment of a symmetric encryption. It also provides the attributes of public verification and forward secrecy. It efficiently makes the SMS messaging suitable for the m-payment applications where the security is the great concern.Comment: 6 Pages, 5 Figure

The effect of height in vaulted tunnels on the stability parameters

This paper presents the effect of height of vaulted tunnels on the stability parameters such as surface settlement, displacement and yielded elements around tunnels. This effect has been investigated in tunnels with different upper arches. Numerical analysis is done by a 2D finite element program with software Phase2, whereby vaulted tunnels are modeled with different upper arches and with widths of 4, 6, 8 and 10 meters and the heights of 3, 5 and 7 meters. The results of the evaluations show that by decreasing the height of tunnels, the stability parameters have improved for all the radius of tunnel arch. Furthermore, variations of the surface settlement, displacement and yielded elements around tunnels has reduced when width of tunnel become larger from radius of tunnel arch

A new approach to content-based file type detection

File type identification and file type clustering may be difficult tasks that have an increasingly importance in the field of computer and network security. Classical methods of file type detection including considering file extensions and magic bytes can be easily spoofed. Content-based file type detection is a newer way that is taken into account recently. In this paper, a new content-based method for the purpose of file type detection and file type clustering is proposed that is based on the PCA and neural networks. The proposed method has a good accuracy and is fast enough.Comment: 6 Pages, 5 Figure, 2 Table