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This paper explores design and implementation of an event-based simulator namely DBMSS for analyzing concurrency protocols in database systems. In the design of DBMSS we interested in event-based approach to create a real world with variety range of event possibilities. DBMSS is explored in the context of the development of a complex simulator for simulating real world conditions and provide an event-based environment to test and evaluate concurrency protocols in database systems. First we discuss the architecture of DBMSS and use it to provide arrival transactions to test and evaluate concurrency protocols in database system. We present the comparison of 4 concurrency protocols in variety... 

A gossip protocol is a procedure for spreading secrets among a group of agents, using a connection graph. The goal is for all agents to get to know all secrets, in which case we call the execution of the protocol successful. We consider distributed and dynamic gossip protocols. In distributed gossip, the agents themselves instead of a global scheduler determine whom to call. In dynamic gossip, not only secrets are exchanged but also telephone numbers (agent identities). This results in increased graph connectivity. We define six such distributed dynamic gossip protocols, and we characterize them in terms of the topology of the graphs on which they are successful, wherein we distinguish... 

This paper proposes a software framework for dynamic-reconfigurable protocol stack. The framework presents mechanisms andan algorithm/or all required phases for reconfiguration of a running protocol component that include freezing the component in a safe state, changing the component, and state transfer to a new component. Considering that every running protocol component communicates with at least one peer component in another system, we perform the reconfiguration with respect to the peer component. © 2007 IEEE  

In the IEEE 802.1D standard for the Media Access Control layer (MAC layer) bridges, there is an STP (Spanning Tree Protocol) definition, based on the algorithm that was proposed by Radia Perlman. In this paper, we give a formal proof for correctness of the STP algorithm by showing that finally a single node is selected as the root of the tree and the loops are eliminated correctly. We use formal inductive reasoning to establish these requirements. In order to ensure that the bridges behave correctly regardless of the topology of the surrounding bridges and LANs, the Rebeca, modular verification techniques are applied. These techniques are shown to be efficiently applicable in model checking... 

Future communication and computation devices require mechanisms for on-the-fly reconfiguration in their protocol stack to operate in different situations and networks. This paper proposes a component-based framework for dynamic-reconfigurable protocol stack. Considering that every running protocol component communicates with at least one peer component, unlike related work our framework supports synchronous reconfiguration of two peer protocol components in two communicating protocol stacks. © Springer-Verlag Berlin Heidelberg 2007  

Nowadays low-cost RFID systems have moved from obscurity into mainstream applications which cause growing security and privacy concernsThe lightweight cryptographic primitives and authentication protocols are indispensable requirements for these devices to grow pervasiveIn recent years, there has been an increasing interest in intuitive analysis of RFID protocolsThis concept has recently been challenged by formal privacy modelsThis paper investigates how to analyse and solve privacy problems in formal modelFirst, we highlight some vague drawbacks especially in forward and backward traceability analysis and extend it in the simulation-based privacy model familyThen, the privacy weaknesses of... 

Privacy is faced with serious challenges in the ubiquitous computing world. In order to handle this problem, some researchers in recent years have focused on design and analysis of privacy-friendly ultralightweight authentication protocols. Although the majority of these schemes have been broken to a greater or lesser extent, most of these attacks are based on ad-hoc methods that are not extensible to a large class of ultralightweight protocols. So this research area still suffers from the lack of structured cryptanalysis and evaluation methods. In this paper, we introduce new frameworks for full disclosure attacks on ultralightweight authentication protocols based on new concepts of... 

Many applications, such as e-passport, e-health, credit cards, and personal devices that utilize Radio frequency Identification (RFID) devices for authentication require strict security and privacy. However, RFID tags suffer from some inherent weaknesses due to restricted hardware capabilities and are vulnerable to eavesdropping, interception, or modification. The synchronization and untraceability characteristics are the major determinants of RFID authentication protocols. They are strongly related to privacy of tags and availability, respectively. In this paper, we analyze a new lightweight RFID authentication protocol, Song and Mitchell, in terms of privacy and security. We prove that not... 

Mobile Ad-hoc Networks (MANETs) are forming dynamically by joining or leaving the nodes into/from the network without any fix infrastructure. It is also possible that each mobile node act as a host or router. This kind of wireless network is prone to various security threats or attacks due to its unique characteristics like dynamic topology, open medium, lack of central monitoring, etc. So security is a vital scope in MANET to protect communication between mobile nodes. Ad-hoc On-demand Distance Vector (AODV) is one of the on-demand reactive routing protocols in MANET that initially was improved without considering security protection. Significant attempts have been done to secure AODV... 

In many wireless communication protocols, small and random delay, called jitter, is imposed before packet transmission so as to reduce packet collisions. Jitter is recommended for many routing protocols such as AODV and LOADng. Jitter can be exploited to change the order of routes about which destination is informed and, as a result, make better routes, regarding their metric, more likely to choose by the destination. However, to the best of our knowledge, there is only one mechanism, called adaptive jitter mechanism, proposed for metric-based routing protocols. In this paper, we aim to show feasibility of using different random variables for jittering and define some shaping functions to... 

In this paper, we propose a new anonymous channel protocol for authentication in GSM mobile communication networks. The protocol is the result of incorporating our anonymity scheme to an efficient GSM authentication protocol proposed by Chang et al. As a result, our protocol has all the features of their scheme including anonymity. Compared with the most recent protocols in this area, such as those by Peinado and Hwang et al., we show that our scheme generally is more secure and more efficient. © 2008, Inderscience Publishers  

In this paper, by making slight modifications in protocol stack of wireless access points, the proposed CICADA scheme aims at isolating problems related to wireless section of a TCP connection from its wired portion, using IP spoofing and Virtual Protocol Stack scheme. As the simulation results for an 802.11 based system show, the proposed scheme improves the overall network throughput while reducing the mean and variance of end-to-end delay for voice and video flows due to smarter bandwidth allocation to elastic and real-time traffic. In addition, the proposed scheme uses a centralized NAT structure that prevents undesired disconnections during handovers and achieves a smaller handoff delay... 

A practical approach to prevent location-based attacks in RFID systems is the use of Distance Bounding (DB) protocols. These protocols enable an entity to determine an upper bound on the physical distance to another entity as well as to authenticate it. It makes, rejection of the requests located out of this distance limitation. So far, many DB protocols have been designed with the aim of resistance to location-based attacks. In this paper, we propose a unilateral DB protocol using delay concept while sending two random binary challenges. This protocol can resist better than other unilateral DB protocols against mafia and distance fraud attacks. In addition, the proposed protocol can be... 

In the past few years, several process-algebraic frameworks have been proposed that incorporate the notion of epistemic knowledge. These frameworks allow for reasoning about knowledge-related properties, such as anonymity, secrecy and authentication, in the operational specifications given in process-algebraic languages. Hitherto, no sound and (ground-)complete axiomatization has been given for the abovementioned process-algebraic frameworks. In this paper, we define notions of bisimulation that are suitable for such process algebras with histories and give a sound and ground-complete axiomatization for the theory of CryptoPAi, which is a process algebra based on Milner's Calculus of... 

A scheme for deterministic secure direct communication based on ping-pong protocol without restricting the security control only to a distinct control mode and debate via classical channel is proposed. It utilizes an entangled pair of qubits and presents a higher bit-rate transfer of information together with a higher security than ping-pong protocol. The security of protocol is enhanced by introducing a control factor for each message mode. It is explicitly showed that the protocol has a high degree of security against a class of individual attacks, and successfully resolves the famous Wojcik attack  

The 3rd Generation Partnership Project (3GPP) defined a new architecture, called Home eNode B (HeNB). HeNB is able to provide new services with higher data rate in a low cost. Security is a critical aspect of HeNB. In order to have HeNB secure access to core network, 3GPP defines an authentication protocol based on IKEv2. A number of security vulnerabilities such as HeNB masquerading have not been addressed and solved by 3GPP technical specification yet. In this paper an improved HeNB authentication protocol is introduced which does not allow an attacker to connect unauthorized network users using a mask. Finally, we evaluate our protocol performance and verify it by Automated Validation of... 

In distributed function computation, each node has an initial value and the goal is to compute a function of these values in a distributed manner. In this paper, we propose a novel token-based approach to compute a wide class of target functions to which we refer as "token-based function computation with memory" (TCM) algorithm. In this approach, node values are attached to tokens and travel across the network. Each pair of travelling tokens would coalesce when they meet, forming a token with a new value as a function of the original token values. In contrast to the coalescing random walk (CRW) algorithm, where token movement is governed by random walk, meeting of tokens in our scheme is... 

To ameliorate high collision, a nefarious side effect of route discovery stage of reactive routing protocols in wireless networks, jitter mechanisms are proposed which enforce wireless nodes to postpone their transmission for a random amount of time so as to reduce probability of simultaneous transmission. Although it has been shown that jitter mechanisms can dramatically improve reactive routing protocols, it was not until recently that jitter mechanisms have been subjected to study. In this paper, different random distributions are proposed for jittering mechanisms and also shaping function, with the aim of which a simple routing protocol like AODV becomes sensitive to any arbitrary... 

We study the extent to which decentralized cost-sharing protocols can achieve good price of anarchy (PoA) bounds in network cost-sharing games with nagents. We focus on the model of resource-aware protocols, where the designer has prior access to the network structure and can also increase the total cost of an edge (overcharging), and we study classes of games with concave or convex cost functions. We first consider concave cost functions and our main result is a cost-sharing protocol for symmetric games on directed acyclic graphs that achieves a PoA of 2+ϵ for some arbitrary small positive ϵ, which improves to 1+ϵ for games with at least two players. We also achieve a PoA of 1 for...