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Unstructured wireless networks such as mobile ad hoc networks and wireless sensor networks have been rapidly growing in the past decade. Security is known as a challenging issue in such networks, in which there is no fixed infrastructure or central trusted authority. Further, node limitations in processing power, storage, and energy consumption add further complexity to addressing security in such networks. While cryptography has proven to be an effective solution capable of satisfying most network security requirements, it requires the use of efficient key pre-distribution algorithms compatible with the limitation of unstructured wireless networks. Typically, a key pre-distribution... 

Key pre-distribution algorithms have recently emerged as efficient alternatives of key management in today's secure communications landscape. Secure routing techniques using key pre-distribution algorithms require special algorithms capable of finding optimal secure overlay paths. To the best of our knowledge, the literature of key pre-distribution systems is still facing a major void in proposing optimal overlay routing algorithms. In the literature work, traditional routing algorithms are typically used twice to find a NETWORK layer path from the source node to the destination and then to find required cryptographic paths. In this paper, we model the problem of secure routing using... 

Many Random Key Distribution (RKD) schemes have been proposed in the literature to enable security applications in Wireless Sensor Networks (WSNs). A main security aspect of RKD schemes is their resistance against node capture attacks, since compromising the sensors and capturing their keys is a common risk in such networks. We propose a new method, based on a 2-Dimensional Hash Chain (2DHC), that can be applied on any RKD scheme to improve their resilience. Our method maintains the flexibility and low cost features of RKD schemes and it doesn't require any special-purpose hardware or extra memory to store keys in the sensors. We demonstrate that our approach significantly increases the... 

This paper combines the cryptanalysis of RC4 and Data mining algorithm. It analyzes RC4 by Data mining algorithm (J48) for the first time and discloses more vulnerabilities of RC4. The motivation for this paper is combining Artificial Intelligence and Machine learning with cryptography to decrypt cyphertext in the shortest possible time. This analysis shows that lots of numbers in RC4 during different permutations and substitutions do not change their positions and are fixed in their places. This means KSA and PRGA are bad shuffle algorithms. In this method, the information theory and Decision trees are used which are very powerful for solving hard problems and extracting information from... 

A multi-stage secret sharing (MSS) scheme is a method of sharing a number of secrets among a set of participants, such that any authorized subset of participants could recover one secret in every stage. The first MSS scheme was proposed by He and Dawson in 1994, based on Shamir's well-known secret sharing scheme and one-way functions. Several other schemes based on different methods have been proposed since then. In this paper, the authors propose an MSS scheme using All-Or-Nothing Transform (AONT) approach. An AONT is an invertible map with the property that having "almost all" bits of its output, one could not obtain any information about the input. This characteristic is employed in the... 

In this paper a reliability, emission, and network security constrained unit commitment (UC) with the focus on wind power integration is formulated. It is shown that clearing both energy and spinning reserve markets taking into account network constraints provides a reliable and economic solution for day-ahead operation planning of a power system with a significant amount of thermal and wind power in the generation portfolio. The developed UC is formulated and implemented in MATLAB. The IEEE 24-Bus Reliability Test System (RTS) is used to verify the UC method by simulation. © 2017 IEEE  

Cloud systems empower the big data management by providing virtual machines (VMs) to process data nodes (DNs) in a faster, cheaper and more effective way. The efficiency of a VM allocation is an important concern that is influenced by the communication latencies. In the literature, it has been proved that the VM assignment minimizing communication latency in the presence of the triangle inequality is 2-approximation. However, a 2-approximation solution is not efficient enough as data center networks are not limited to the triangle inequality. In this paper, we define the quadrilateral inequality property for latencies such that the time complexity of the VM assignment problem minimizing... 

This paper presents a novel approach for power allocation and cooperative node selection to enhance physical layer security in presence of an eavesdropper in a wireless network. Our network consists of a source–destination pair and a number of cooperative nodes which can be used as relays to increase throughput at the destination, or as friendly jammers to confuse eavesdropper. First, we introduce a low complexity method, for which relay−jammer selection and power allocation are performed, simultaneously. Then, we propose self-adaptive genetic algorithm to solve the non-linear non-convex programing problem. Using the proposed method, the number of friendly jammers that ensure the secrecy... 

With the development of modern power systems, Smart Grid as the intelligent generation of electricity networks, has been faced with a tremendous attention. The Smart Grid systems are made up of fine-grained power grid measurements to achieve a high stability and reliability. In these networks, the data security and privacy issues for secure data sharing among the components of the system have emerged as the basic requirement. Typically, a service provider securely shares the data/commands with the smart meters under an arbitrary policy which is determined by the service providers. As the smart grid components are considered to have constrained computational resources, we cannot directly use... 

Node cooperation approaches improve physical layer security in wireless networks without applying data encryption. Selecting the appropriate nodes to cooperate as relays or friendly jammers, to degrade eavesdropper's link, is a challenging problem which has attracted a lot of attention in recent years. Various approaches, based on conventional exhaustive search, have been suggested for optimal relay-jammer selection and power allocation in the literature. The complexity of these methods is proportional to the number of intermediate nodes. As the number of intermediate nodes exceeds a specific bound, conventional exhaustive search appears infeasible due to high computational complexity. In... 

We investigate large wireless networks subject to security constraints. In contrast to point-to-point, interferencelimited communications considered in prior works, we propose active cooperative relaying-based schemes. We consider a network with nl legitimate nodes, ne eavesdroppers, and path loss exponent α ≥ 2. As long as n2e (log(ne))γ = o(nl ), for some positive γ , we show that one can obtain unbounded secure aggregate rate. This means zero-cost secure communication, given fixed total power constraint for the entire network. We achieve this result through: 1) the source using Wyner randomized encoder and a serial (multi-stage) block Markov scheme, to cooperate with the relays and 2) the... 

Dynamic nature of mobile ad hoc networks combined with their lack of centralized infrastructure make security problem the most challenging issue in such networks. The main contribution of this paper is to propose a secure and efficient key management algorithm, able to satisfying the requirement of such networks and facing their specific characteristics. The proposed algorithm is a fully distributed ID-based system which is built based on elliptic curve cryptography. The main advantage of the proposed algorithm, that gives it the superiority in its field of research, is the improvement of the performance and the security strength together. The proposed algorithm is implemented with much... 

In recent years, determining the common information privately and efficiently between two mutually mistrusting parties have become an important issue in social networks. Many Private set intersection (PSI) protocols have been introduced to address this issue. By applying these protocols, two parties can compute the intersection between their sets without disclosing any information about components that are not in the intersection. Due to the broad range of computational resources that the cloud can provide for its users, determining the set intersection by cloud may decrease the computational cost of the users. The proposed protocol by Abadi et al. is one of the introduced protocols in this... 

Design of anonymous authentication scheme is one of the most important challenges in Vehicular Ad hoc Networks (VANET). Most of the existing schemes have high computational and communication overhead and they do not meet security requirements. Recently, Azees et al. have introduced an Efficient Anonymous Authentication with Conditional Privacy-Preserving (EAAP) scheme for VANET and claimed that it is secure. In this paper, we show that this protocol is vulnerable against replay attack, impersonation attack and message modification attack. Also, we show that the messages sent by a vehicle are linkable. Therefore, an adversary can easily track the vehicles. In addition, it is shown that... 

Signatures with partially message recovery in which some parts of messages are not transmitted with signatures to make them shorter are helpful where bandwidth is one of the critical concern. This primitive is especially used for signing short messages in applications such as time stamping, certified email services, and identity-based cryptosystems. In this paper, to have quantum-attack-resistant short signatures, the first signature scheme with partially message recovery based on coding theory is presented. Next, it is shown that the proposal is secure under Goppa Parametrized Bounded Decoding and the Goppa Code Distinguishing assumptions in the random oracle model. Relying on the partially... 

In cryptographic engineering, extensive attention has been devoted to ameliorating the performance and security of the algorithms within. Nonetheless, in the state-of-the-art, the approaches for increasing the reliability of the efficient hash functions ECHO and Fugue have not been presented to date.We propose efficient fault detection schemes by presenting closed formulations for the predicted signatures of different transformations in these algorithms. These signatures are derived to achieve low overhead for the specific transformations and can be tailored to include byte/word-wide predicted signatures. Through simulations, we show that the proposed fault detection schemes are... 

Data skew, which is the result of uneven distribution of data among tasks in big data processing frameworks such as MapReduce, causes significant variation in the execution time of tasks and makes their placement on computing resources more challenging. Moreover, with the proliferation of big data processing in the cloud, the interference among virtual machines co-located on the same physical machine exacerbates the aforementioned variation. To tackle this challenge, we propose Locality and Interference aware Portfolio-based Task Assignment (LIPTA) approach. LIPTA leverages the modern portfolio theory to mitigate the variation in execution time of tasks while considering the interference of... 

Concurrent signatures allow two entities to generate two signatures in such a way that both signatures are ambiguous till some information is revealed by one of the parties. This kind of signature is useful in auction protocols and in a wide range of scenarios in which involving participants are mutually distrustful. In this study, to have quantum-attack-resistant concurrent signatures as recommended by National Institute of Standards and Technology (NISTIR 8105), the first concurrent signature scheme based on coding theory is proposed. Then, its security is proved under Goppa Parameterized Bounded Decoding and the Goppa Code Distinguishing assumptions in the random oracle model. In... 

In this paper, we consider the problem of searching a network for intruders. We propose a strategy for capturing the intruder in the popular interconnection topology, the star network. According to the proposed strategy, a team of collaborative software agents are responsible for capturing a hostile intruder (e.g. a virus). These agents asynchronously move along the network links and the intruder has the capability of escaping arbitrarily fast. © 2009 IEEE  

In this paper we propose two mutual authentication protocols for RFID systems. Generally, in RFID systems, a reader can authenticate tags in the real-time and batch modes. This paper proposes the first authentication protocol for the real-time mode. It also proposes an efficient robust mutual authentication protocol for the batch mode. Some significant characteristics of the protocols are forward security, tag anonymity, location privacy, low complexity on the back-end server, and scalability. To the best of our knowledge, our protocols offer the most enhanced security features in RFID mutual authentication protocols with respect to user privacy. In analyzing the protocols, we show how...