Biblio

Remote user authentication using smart cards is a method of verifying the legitimacy of remote users accessing the server through insecure channel, by using smart cards to increase the efficiency of the system. During last couple of years many protocols to authenticate remote users using smart cards have been proposed. But unfortunately, most of them are proved to be unsecure against various attacks. Recently this year, Yung-Cheng Lee improved Shin et al.'s protocol and claimed that their protocol is more secure. In this article, we have shown that Yung-Cheng-Lee's protocol too has defects. It does not provide user anonymity; it is vulnerable to Denial-of-Service attack, Session key reveal, user impersonation attack, Server impersonation attack and insider attacks. Further it is not efficient in password change phase since it requires communication with server and uses verification table.
 

Data deduplication is a technique for eliminating duplicate copies of data, and has been widely used in cloud storage to reduce storage space and upload bandwidth. Promising as it is, an arising challenge is to perform secure deduplication in cloud storage. Although convergent encryption has been extensively adopted for secure deduplication, a critical issue of making convergent encryption practical is to efficiently and reliably manage a huge number of convergent keys. This paper makes the first attempt to formally address the problem of achieving efficient and reliable key management in secure deduplication. We first introduce a baseline approach in which each user holds an independent master key for encrypting the convergent keys and outsourcing them to the cloud. However, such a baseline key management scheme generates an enormous number of keys with the increasing number of users and requires users to dedicatedly protect the master keys. To this end, we propose Dekey , a new construction in which users do not need to manage any keys on their own but instead securely distribute the convergent key shares across multiple servers. Security analysis demonstrates that Dekey is secure in terms of the definitions specified in the proposed security model. As a proof of concept, we implement Dekey using the Ramp secret sharing scheme and demonstrate that Dekey incurs limited overhead in realistic environments.

In this paper, we propose a remote password authentication scheme based on 3-D geometry with biometric value of a user. It is simple and practically useful and also a legal user can freely choose and change his password using smart card that contains some information. The security of the system depends on the points on the diagonal of a cuboid in 3D environment. Using biometric value makes the points more secure because the characteristics of the body parts cannot be copied or stolen.
 

Multiple Security Domains Nondeducibility, MSDND, yields results even when the attack hides important information from electronic monitors and human operators. Because MSDND is based upon modal frames, it is able to analyze the event system as it progresses rather than relying on traces of the system. Not only does it provide results as the system evolves, MSDND can point out attacks designed to be missed in other security models. This work examines information flow disruption attacks such as Stuxnet and formally explains the role that implicit trust in the cyber security of a cyber physical system (CPS) plays in the success of the attack. The fact that the attack hides behind MSDND can be used to help secure the system by modifications to break MSDND and leave the attack nowhere to hide. Modal operators are defined to allow the manipulation of belief and trust states within the model. We show how the attack hides and uses the operator's trust to remain undetected. In fact, trust in the CPS is key to the success of the attack.