Abstract

The purpose of this research is to explore the possibilities and mechanisms to be followed in order to extend the QoS in the backbone networks. This paper extends the ideas discussed in my previous paper: A Novel Architecture to Enhance Quality of Service in IP Networks [1] explaining the consequences of the proposal and building a model network. Simulated an SDN network using mininet and presented the packet captures depicting the extension of QoS outside the access networks.

Abstract

Authentication schemes are widely used mechanisms to thwart unauthorized access of resources over insecure networks.Several smart card based password authentication schemes have been proposed in the literature. In this paper, we demonstrate the security limitations of a recently proposed password based authentication scheme, and show that their scheme is still vulnerable to forgery and offline password guessing attacks and it is also unable to provide user anonymity, forward secrecy and mutual authentication. With the intention of fixing the weaknesses of that scheme, we present a secure authentication scheme. We show that the proposed scheme is invulnerable to various attacks together with attacks observed in the analyzed scheme through both rigorous formal and informal security analysis. Furthermore, the security analysis using the widely-accepted Real-Or-Random (ROR) model ensures that the proposed scheme provides the session key (SK) security. Finally,we carry out the performance evaluation of the proposed scheme and other related schemes, and the result favors that the proposed scheme provides better trade-off among security and performance as compared to other existing related schemes.

Abstract

In a synchronous distributed network of n nodes, the goal of a Secure Message Transmission (SMT) protocol is to securely deliver the sender’s message at the receiver’s end in the presence of a computationally unbounded adversary that can partially control the network by corrupting some of its nodes (except the sender and the receiver). In a network modelled as a directed graph, to achieve unconditional security tolerating tb Byzantine faults, it is known that: (1) if all the paths are one-way connected from the sender to the receiver – called as forward channels – then 2tb + 1 vertex-disjoint forward channels are necessary and sufficient (2) for 1 ≤ u ≤ tb, if there exist 2tb + 1 − u vertex-disjoint forward channels then u vertex-disjoint paths from the receiver to the sender – known as feedback channels – are necessary and sufficient. Moreover, similar characterization exists for tolerating mixed faults – up to t f fail-stop faults in addition to tp passive faults. We notice that these results characterized the networks by studying the required number of extra vertex-disjoint feedback channels, conditioned on the existence of a certain number of forward channels. In this work, we give a generic characterization without attaching any such if condition. Specifically, we answer the following questions. In a given directed graph, that is abstracted as a collection of strong paths from S to R and R to S, under what conditions is SMT (im)possible tolerating: (1) up to tp passive faults?, (2) mixed faults – up to t f fail-stop faults in addition to tp passive faults?, and (3) up to tb Byzantine faults? Also, for each of these three problems, we explicitly show that there are networks in which SMT protocols exist whereas the existing results do not characterize such networks.

Abstract

With the increasing use of mobile devices, a secure communication and key exchange become the significant security issues in mobile environments. However, because of open network envi-ronments, mobile user can be vulnerable to various attacks. Therefore, the numerous authentication and key exchange schemes have been proposed to provide the secure communication and key exchange.Recently, Qi and Chen proposed an efficient two-party authentication key exchange protocol for mobile environments in order to overcome the security weaknesses of the previous authentication and key exchange schemes. However, we demonstrate that Qi and Chen’s scheme is vulnerable to various attacks such as impersonation, offline password guessing, password change, and privileged insider attacks. We also show that Qi and Chen’s scheme does not provide anonymity, efficient password change mechanism, and secure mutual authentication. In this paper, to overcome the outlined above mentioned security vulnerabilities,we propose a secure and efficient two-party authentication key exchange protocol, called 2PAKEP, that hides user’s real identity from an adversary using a secret parameter. 2PAKEP also withstands various attacks, guarantees anonymity, and provides efficient password change mechanism and secure mutual authentication. In addition, we prove that 2PAKEP provides the secure mutual authentication using the broadly accepted Burrows–Abadi–Needham logic and the session key security using the formal security analysis under the widely accepted real-or-random model. Moreover, the formal security verification using the popular simulated software tool, Automated Validation of Internet Security Protocols and Applications,on 2PAKEP shows that the replay and man-in-the-middle attacks are protected. In addition, we also analyze the performance and security and functionality properties of 2PAKEP and compare these with the related existing schemes. Overall, 2PAKEP provides better security and functionality features, and also the communication and computational overheads are comparable with the related schemes. Therefore, 2PAKEPis applicable to mobile environment efficiently.

Abstract

Steerability is a characteristic non-local trait of quantum states lying in between entanglement and Bell non-locality. A given quantum state is considered to be steerable if it violates a suitably chosen steering inequality. A quantum state which otherwise satisfies a certain inequality can violate the inequality under a global change of basis, i.e., if the state is transformed by a non-local unitary operation. Intriguingly, there are states which preserve their non-violation (pertaining to the said inequality) under any global unitary operation. The present work explores the effect of global unitary operations on the steering ability of a quantum state which lives in two qubits. We characterize such states in terms of a necessary and sufficient condition on their spectrum. Such states are also characterized in terms of some analytic characteristics of the set to which they belong. Looking back at steerability the present work also provides a relation between steerability and quantum teleportation together with the derivation of a result related to the optimal violation of steering inequality. An analytic estimation of the size of such non-violating states in terms of purity is also obtained. Interestingly, the estimation in terms of purity also gives a necessary and sufficient condition in terms of Bloch parameters of the state. Illustrations from some signature class of quantum states further underscore our observations.

Abstract

The Internet of Things (IoT) is a system of physical as well as virtual objects (each with networking capabilities incorporated) that are interconnected to exchange and collect information locally or remotely over the Internet. Since the communication often takes place over the Internet, it is vulnerable to various security threats in an IoT environment. We first discuss essential security requirements that are needed to secure IoT environment. We also discuss the threat model and various attacks related to the IoT environment. We then present a taxonomy of security protocols for the IoT environment which includes important security services such as key management, user and device authentication, access control, privacy preservation, and identity management. We also present a comparative study of recently proposed IoT-related state-of-art security protocols in terms of various security and functionality features they support. Finally, we discuss some future challenges for IoT security protocols that need to be addressed in the future.

Abstract

In this work we introduce the randomness which is truly quantum mechanical in nature arising as an act of measurement. For a composite classical system we have the joint entropy to quantify the randomness present in the total system and that happens to be equal to the sum of the entropy of one subsystem and the conditional entropy of the other subsystem given we know the first system. The same analogy caries over to the quantum setting by replacing the Shannon entropy by the Von Neumann entropy. However, if we replace the conditional von Neumann entropy by the average conditional entropy due to measurement, we find that it is different from the joint entropy of the system. We call this difference Measurement Induced Randomness (MIR) and argue that this is unique of quantum mechanical systems and there is no classical counterpart to this. In other words the joint Von Neumann entropy gives only the total randomness that arises because of the heterogeneity of the mixture and we show that it is not the total randomness that can be generated in the composite system. We generalize this quantity for N-qubit systems and show that it reduces to quantum discord for two qubit systems. Further, we show that it is exactly equal to the change in the cost of quantum state merging that arises because of the measurement. We argue that for a quantum information processing tasks like state merging the change in the cost as a result of discarding prior information can also be viewed as a rise of randomness due to measurement.

Abstract

Remote user authentication is a cryptographic mechanism through which a remote server verifies the legitimacy of an authorized user over an insecure communication channel. Most of the existing authentication schemes consider single-server environments and require multiple registrations of the sameuser for multiple servers. Moreover, most of these schemes do not consider biometric template revocation and error correction for noisy biometric signals. In addition, the existing schemes have several weaknesses,including stolen smart card attack, lack of user anonymity, user impersonation attack, and non-diversification of biometric data. To overcome these disadvantages, we propose a new three-factor authenticated key agreement scheme using a fuzzy commitment approach. The three factors used in the proposed scheme are the user’s password, smart card, and personal biometrics. The security of the proposed scheme is verified using a formal security analysis under the broadly accepted Real-Or-Random model for the session key security. The widely accepted Burrows-Abadi-Needham logic is also applied for mutual authentication between a legally registered user and a server, and formal security verification using the broadly accepted Automated Validation of Internet Security Protocols and Applications is performed for the proposed scheme through simulation to show that it is secure. In addition, the informal security analysis of the proposed scheme shows that the scheme can resist other known attacks. Finally, a comparative study of the proposed scheme with the existing related schemes is conducted to measure the trade off among the security and functionality features and the communication and computation costs

Abstract

We consider causality respecting (CR) quantum systems interacting with closed timelike curves (CTCs), within the Deutsch model. We introduce the concepts of popping-up and elimination of quantum information and use them to show that no-cloning and no-deleting, which are true in CR quantum systems, are no more valid in the same that are interacting with CTCs. We also find limits on the possibility of creation of entanglement between a CR system and a CTC, and the same between two CR systems in the presence of a CTC. We prove that teleportation of quantum information, even in its approximate version, from a CR region to a CTC is disallowed. Interestingly, we find that tweaking the Deutsch model, by allowing the input and output not to be the same, leads to a nontrivial approximate teleportation beyond the classical limit.

Abstract

The Internet of Drones (IoD) provides the coordinated access to controlled airspace for the Unmanned Aerial Vehicles (called drones). The on-going cheaper costs of sensors and processors, and also wireless connectivity make it feasible to use the drones for several applications ranging from military to civilian. Since most of the applications using the drones involved in the IoD are real-time based applications, the users (external parties) usually have their interest in getting the real-time services from the deployed drones belonging to a particular fly zone. To address this important issue in the IoD, there is a great need of an efficient and secure user authentication approach in which an authorized user (for example, a driver of an ambulance) in the IoD environment can be given access to the data directly from an accessed drone. In this article, we first discuss an authentication model used in the IoD communication. We then discuss some security challenges and requirements for the IoD environment. A taxonomy of various security protocols in the IoD environment is also discussed. We then emphasis on the study of some recently proposed user authentication schemes for the IoD communication. A detailed comparative study is done based on functionality features, security attacks, and also communication and computation costs. Through the rigorous comparative study of the existing schemes, we identify the strengths and weaknesses of the user authentication schemes for the IoD communication. Finally, we identify some of the challenges for the IoD that need to be addressed in the coming future