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Current networking technologies are not perfectly equipped to support Quality of Service (QoS), which is vital for real-time multimedia applications in Wireless Community Mesh Networks (WCNs). Therefore, there is a need to devise innovative routing algorithms to support QoS on top of existing standards. Thus, this paper presents a cross layer relay node selection model for routing protocols in order to offer optimal routes to real-time applications. To the best of our knowledge, our two proposed routing metrics, Packet Priority-Oriented routing metric (PPO) and Packet Priority-oriented QoS routing metric (PP-QoS) , are the first to provide differentiated priorities and service levels to applications with different needs. PPO considers the application priority. Moreover, PP-QoS also considers the channel busy level to improve the performance of path selection. The simulation confirms the superiority of the proposed model against a number of existing counterparts. [ABSTRACT FROM AUTHOR]

The increasing costs of healthcare along with the increasing availability of new Personal Health Devices (PHDs) are the ingredients of the connected health vision. Also, a growing number of consumer electronic and mobile devices are becoming capable of taking the role of a health gateway, thus operating as a data collector for PHDs. In this context, we present a system that enables PHDs to share information in home networks and with the Internet based on a new Internet of Things protocol, namely the Constrained Application Protocol (CoAP). CoAP is used along with the IEEE 11073 family of standards, which is the main exchange data model for PHD communication. We discuss how the proposed system can be integrated to other connected health systems, such as a Universal Plug and Play healthcare system. We detail how the CoAP communication model was adapted to the IEEE 11073 model. We also present a real PHD prototype and its evaluation results. These results demonstrated the feasibility of the proposed solution, showing how its network overhead is around 50% lighter when compared to other protocols. Finally, we tested the proposed solution based on different scenarios, including a proof-of-concept integration with a service in the cloud, using different wireless physical interfaces. [ABSTRACT FROM AUTHOR]

Abstract: Wireless data broadcast is an important data dissemination method for distributing public information to mobile users. Due to the exponentially increasing number of mobile network users, it is necessary to develop efficient data retrieval protocols for end users to download data items effectively. In this paper, we concentrate on investigating scheduling algorithms for retrieving a set of data items from a multichannel wireless data broadcast system. As we know, the most important issues in mobile computing are energy efficiency and query response efficiency. However, in data broadcast the objectives of reducing access latency and energy cost can be contradictive to each other. Consequently, we define a new problem named Minimum Constraint Data Retrieval Problem (MCDR). We prove that MCDR is NP-hard, and then show a fixed parameter tractable algorithm which can balance two factors together. It has computational time , where is the number of channels, is the number of required data items, is the maximal time slot, and is the maximal number of channel switches. [Copyright &y& Elsevier]

Abstract: Recently, many works have been focusing on solving the problem of privacy protection at link-layer level by randomizing all bits of the frames at link layer so that it makes difficult for unintended recipients to associate sequences of packets to their source transmitters. Most existing schemes however assume either the pre-setup for shared secrets between communication entities or the use of public-key infrastructure. These requirements limit the use of the schemes. In this paper, we describe new techniques for protecting the privacy and security of communication entities at wireless link-layer level. Our techniques have a number of crucial advantages. They mitigate the requirement of a key setup or a public-key infrastructure. They provide not only the link-layer privacy, but also the required security properties, including key compromise impersonation resilience, impersonation resistance and forward secrecy. They are simple and relatively fast. [Copyright &y& Elsevier]

Abstract: Various wireless technologies including radio frequency identification (RFID), bluetooth, cellular networks and dedicated short range communications (DSRC) might have an impact on logistics and transport operations. Among them, DSRC stands out as a broadband communications technology which has been designed to provide a general purpose Radio-Frequency (RF) link between vehicles and network infrastructure. As such, DSRC is capable of implementing the physical layer of an Internet Protocol (IP) bearer based network designed to facilitate the monitoring and coordination of portside vehicular traffic. This unprecedented application of wireless networking has the potential to greatly enhance the management of the flow of goods and resources, particularly within large, international ports whose activities comprise multimodal operations such as the use of road haulage to move cargo transported by sea. Given the need for reliable services in non-safety business applications, in this work an Intelligent Transport Systems (ITS) approach is used to address two issues. First, in wireless networks reliable data transfer transport layer services are affected where there is an apparent increase in mobility when access point coverage areas are reduced to counter the effects of path loss in the physical layer. Second, a service provisioning protocol intended for vehicle to infrastructure (V2I) data transfer is proposed to illustrate the importance of cumulative costs in wireless networks used for logistics applications. The analysis covers the average response time for requesting on-demand services within the portside network considered. The results of the analysis confirm the suitability of the approach used to provide a logistics network capable of meeting the requirements demanded in multimodal logistics. [Copyright &y& Elsevier]

Abstract: In the mobile asset management services applicable to warehouse, hospital, etc. a low-cost and practical bidirectional location tracking of mobile asset is one of the most important technical issue must be solved. Due to the complexity and heavy traffic of the legacy location-awareness techniques, simultaneous locationing and tracking of numerous mobile nodes in real-time is not easy. To address this problem, we propose the three-tier middleware architecture called uMATI (ubiquitous Mobile Asset Tracking Infra). In the uMATI, all nodes (stationary and mobile) commonly use the IEEE 802.15.4 MAC protocol to guarantee the compatibility with the legacy wireless sensor network (WSN) despite of mobile-stationary nodes co-existence network. To solve the bidirectional tracking in spite of the free mobility of the numerous mobile nodes, we firstly suggest a simple bidirectional location protocol called BLIDx (bidirectional location ID exchange) and its implementation into both the mobile and stationary nodes. In addition, to prevent the traffic overflow due to the concentration of excessive mobile nodes into a single location, we propose adding a specially designed stationary node called virtual sink (VS) node and installing related middleware components into the node. Results from the experimental evaluation prove that the proposed architecture enhanced the practicability by effectively supporting the mobility and managing the traffic in the real-time mobile asset tracking applications. [Copyright &y& Elsevier]

Abstract: A wireless sensor network is a set of nodes, each is equipped with a sensing device and a wireless communication device. Because centralized control is hard to achieve in a large scale sensor network, self- is a key concept in the design of a wireless sensor network. Self-stabilization is one of the self- properties, and it is one of the most promising theoretical backgrounds for self-organizing wireless sensor network protocols. Herman [T. Herman, Models of self-stabilization and sensor networks, in: Proceedings of the 5th International Workshop of Distributed Computing, IWDC, 2003, pp. 205–214] proposed Cached Sensornet Transform (CST for short) for design and implementation of self-stabilizing algorithms for sensor networks. It transforms a self-stabilizing algorithm in a high-level computational model to a program for sensor networks. Our contribution in this paper is threefold. We show that there exists a non-silent algorithm that behaves correctly in a high-level computational model but its transformed version by CST does not behave correctly if packets are lost. We show a sufficient condition for original algorithms and networks such that the algorithm transformed by CST behaves correctly. As a case study, we present a token circulation algorithm that behaves correctly by CST and derive the upper bound of its expected convergence time. [Copyright &y& Elsevier]

Abstract: TCP over wireless networks is challenging due to random losses and ACK interference. Although network coding schemes have been proposed to improve TCP robustness against extreme random losses, a critical problem still remains of DATA–ACK interference. To address this issue, we use inter-flow coding between DATA and ACK to reduce the number of transmissions among nodes. In addition, we also utilize a “pipeline” random linear coding scheme with adaptive redundancy to overcome high packet loss over unreliable links. The resulting coding scheme, ComboCoding, combines intra-flow and inter-flow coding to provide robust TCP transmission in disruptive wireless networks. The main contributions of our scheme are twofold; the efficient combination of random linear coding and XOR coding on bi-directional streams (DATA and ACK), and the novel redundancy control scheme that adapts to time-varying and space-varying link loss. The adaptive ComboCoding was tested on a variable hop string topology with unstable links and on a multipath MANET with dynamic topology. Simulation results show that TCP with ComboCoding delivers higher throughput than with other coding options in high loss and mobile scenarios, while introducing minimal overhead in normal operation. [Copyright &y& Elsevier]

Abstract: In this contribution a novel model-based solution approach is introduced for medical networks and biotelemetric applications. Medical networks are communication networks that serve for the purpose of monitoring and protecting human health. These networks are designed to use biotelemetric ways to transmit the vital data to health observers such as doctors, nurses, first-aid teams, hospitals, and health agencies. These networks are also used in collective damages that may occur in situations such as flood, earthquake, war and terror and for treatments and follow-up of patients and to organize health teams more effective and efficiently. Implementations using this model presented here provides a reference design. In addition MCP (Medical Communication Protocol) and MMP (Medical Management Protocol) are designed to reveal how communications between modules designed. In this way, communication rules explained clearly on developed solution based on the model. [Copyright &y& Elsevier]

Abstract: This paper reports a feasibility analysis of the use of a hybrid control network based on the Common Industrial Protocol (CIP). For this feasibility analysis, the message service time between DeviceNet and the wireless devices is investigated. The feasibility of hybrid control networks is analyzed using a mathematical analysis and experimental tests. The experimental results show the feasibility of the hybrid control networks in terms of the polling/COS service time and the average end-to-end delays. [Copyright &y& Elsevier]

Abstract: Wireless technologies which serve multimedia applications have to guarantee the Quality of Service (QoS) demands along with seamless connectivity. The complexity in attaining such demands increases if the network is heterogeneous in nature. This paper proposes a QoS guaranteed integration methodology for a heterogeneous wireless local area network (WLAN) – worldwide interoperability for microwave access (WiMAX) network. An integrated protocol stack for the mobile terminal which could work in a WLAN–WiMAX heterogeneous network is proposed. The proposed integrated protocol stack, a blend of two modules namely generic virtual link layer (GVLL) and media independent handover (MIH) is placed above the media access control (MAC) layer which includes both WLAN and WiMAX MAC. The impact of GVLL in guaranteeing the QoS on QoS deterioration and the impact of MIH in attaining seamless handover are analyzed and the results are presented. [Copyright &y& Elsevier]

Abstract: Group key agreement is the core of secure group communication. In wireless networks, the privacy problem becomes more crucial and urgent for mobile users due to the open nature of radio media. In this paper, we proposed a novel group key agreement protocol based on trusted third Party, applied in collaboration between mobile users for wireless Mesh network. The security verification (PCL logic) and performance analysis show that, our protocol not only provides privacy protection for group members, but also authenticates all participants by adopting certificates. More important, in the proposed protocol, the computation cost and traffics for each group member are largely reduced to improve the implementation efficiency of the protocol. Therefore, our protocol is a novel, reliable group key agreement protocol, and it is well suited for wireless mesh network. [Copyright &y& Elsevier]

Abstract: Applications of wireless communications networks are emerging continuously. To offer a good level of security in these applications, new standards for wireless communications propose solutions based on cryptographic algorithms working on special modes of operation. This work presents a custom hardware architecture for the AES-CCM protocol (AES-CCMP) which is the basis for the security architecture of the IEEE 802.11i standard. AES-CCMP is based on the AES-CCM algorithm that performs the Advanced Encryption Standard (AES) in CTR with CBC-MAC mode (CCM mode), plus specialized data formatting modules, providing different security services through iterative and complex operations. Results of implementing the proposed architecture targeting FPGA devices are presented and discussed. A comparison against similar works shows significant improvements in terms of both throughput and efficiency. [Copyright &y& Elsevier]

Abstract: In wireless systems, the communication mechanism combines features of broadcast, synchrony, and asynchrony. We develop an operational semantics for a calculus of wireless systems. We present different Reduction Semantics and a Labelled Transition Semantics and prove correspondence results between them. Finally, we apply CWS to the modelling of the Alternating Bit Protocol, and prove a simple correctness result as an example of the kind of properties that can be formalized in this framework. A major goal of the semantics is to describe the forms of interference among the activities of processes that are peculiar of wireless systems. Such interference occurs when a location is simultaneously reached by two transmissions. The Reduction Semantics differ on how information about the active transmissions is managed. We use the calculus to describe and analyse a few properties of a version of the Alternating Bit Protocol. [Copyright &y& Elsevier]

Abstract: With the ever-increasing demand for wireless real-time services and continuing emergence of new multimedia applications especially for mobile users, it is necessary for the network to support various levels of quality of service (QoS) while maximizing the utilization of scarce and expensive wireless channel resources. Considering this fact, a new TDMA/FDD MAC protocol integrating a novel QoS management algorithm and multi-beam Directional Antennas (DAs) to efficiently exploit wireless resources has been developed and presented in this paper. It supports all ATM CBR, VBR, ABR and UBR service classes by adopting a well-managed dynamic guarantee-based QoS scheduling algorithm. The work mainly aims at increasing the wireless system throughput as well as improving the call-blocking ratios and end-to-end delays for real-time applications. This seamless communication enables both handling real-time multimedia traffics in a fair manner and granting call requests on the basis of the connection types. The system has been developed, modeled and simulated using OPNET Modeler. The simulation results show that the QoS-aware TDMA/FDD MAC with multi-beam DAs has substantially increased the system throughput and that the call-blocking ratio has been reduced from 86% to 18%, when the proposed MAC with 8-Beam antennas is employed instead of the regular MAC. [Copyright &y& Elsevier]

Abstract: Ad hoc networks consist of wireless hosts that communicate with each other in the absence of a fixed infrastructure. Such networks cannot rely on centralized and organized network management. The clustering problem consists of partitioning network nodes into non-overlapping groups called clusters. Clusters give a hierarchical organization to the network that facilitates network management and that increases its scalability. In a weight-based clustering algorithm, the clusterheads are selected according to their weight (a node’s parameter). The higher the weight of a node, the more suitable this node is for the role of clusterhead. In ad hoc networks, the amount of bandwidth, memory space or battery power of a node could be used to determine weight values. A self-stabilizing algorithm, regardless of the initial system configuration, converges to legitimate configurations without external intervention. Due to this property, self-stabilizing algorithms tolerate transient faults and they are adaptive to any topology change. In this paper, we present a robust self-stabilizing weight-based clustering algorithm for ad hoc networks. The robustness property guarantees that, starting from an arbitrary configuration, after one asynchronous round, the network is partitioned into clusters. After that, the network stays partitioned during the convergence phase toward a legitimate configuration where the clusters verify the “ad hoc clustering properties”. [Copyright &y& Elsevier]

Abstract: This paper is focused on the validation by means of physical fault injection at pin-level of a time-triggered communication controller: the TTP/C versions C1 and C2. The controller is a commercial off-the-shelf product used in the design of by-wire systems. Drive-by-wire and fly-by-wire active safety controls aim to prevent accidents. They are considered to be of critical importance because a serious situation may directly affect user safety. Therefore, dependability assessment is vital in their design. This work was funded by the European project ‘Fault Injection for TTA’ and it is divided into two parts. In the first part, there is a verification of the dependability specifications of the TTP communication protocol, based on TTA, in the presence of faults directly induced in communication lines. The second part contains a validation and improvement proposal for the architecture in case of data errors. Such errors are due to faults that occurred during writing (or reading) actions on memory or during data storage. [Copyright &y& Elsevier]

Abstract: Due to the rapid growth in popularity of Wireless Local Area Network (WLAN), wireless security has become one of many important research issues. For the WLAN security, the IEEE 802.1X standard provides an authentication framework that is based on the Extensible Authentication Protocols (EAP). In the EAP framework, there are many authentication protocols that have been proposed, in which each authentication protocol has some strengths and weaknesses, respectively. Most EAP authentication protocols lack two features: identity protection and withstanding man-in-the-middle attacks. In this paper, we first propose a novel symmetric-key based certificate distribution scheme based on Universal Subscriber Identity Module (USIM) cards in a cellular network. The symmetric-key based certificate distribution scheme allows mobile subscribers to obtain temporary certificates from the corresponding cellular network. Combining the proposed certificate distribution scheme with the EAP-TLS (Transport Layer Security) protocol, we present a new EAP authentication protocol called USIM-based EAP authentication protocol. The new EAP authentication protocol combining with USIM cards is an extension of the EAP-TLS protocol and also follows the EAP framework in the IEEE 802.1X standard. Compared to other EAP authentication protocols, the proposed protocol provides mutual authentication, strong identity protection and roaming capability between the cellular network and the WLAN networks. [Copyright &y& Elsevier]

Abstract: Media access protocols in wireless networks require each contending node to wait for a backoff time, chosen randomly from a fixed range, before attempting to transmit on a shared channel. However, nodes acting in their own selfish interest may not follow the protocol. In this paper, a static version of the problem is modeled as a strategic game played by non-cooperating, rational players (the nodes). The objective is to design a game which exhibits a unique, a priori mixed-strategy Nash equilibrium. In the context of the media access problem, the equilibrium of the game would correspond to nodes choosing backoff times randomly from a given range of values, according to the given distribution. We consider natural variations of the problems concerning the number of actions available to the players and show that it is possible to design such a game when there are at least two players that each have the largest number of possible actions among all players. In contrast, we show that if there are exactly two players with different number of actions available to them, then it becomes impossible to design a strategic game with a unique such Nash equilibrium. [Copyright &y& Elsevier]

Abstract: Conference call is a key functionality that a wireless network should support. When a conference call is set up in a wireless network, conference attendees should be authenticated. In many applications, the attendees also need to be anonymous. In this paper, we propose a very efficient protocol for authenticated and anonymous conference key setup. Our protocol uses only symmetric-key encryptions/decryptions and hashing and is thus much faster than any existing protocol using public-key cryptography. In addition to the conference key setup protocol, we also present two protocols, for authenticated call setup and authenticated handoff, respectively. These two protocols are also much faster than existing protocols based on public-key cryptography. Consequently, a system using the three protocols presented in this paper will have both high security and high efficiency. [Copyright &y& Elsevier]

Wireless LAN networking is an indispensable technology in an All-IP network architecture to satisfy the “anytime and anywhere” communication requirement of end users. This investigation proposes feedback controllers designing based on dynamic quality-of-service requirement for wireless LAN multimedia services. During the controllers design process, the time-domain is replaced by the s-domain, simplifying the calculation. This work presents three controllers namely proportional integral (PI), proportional derivative (PD) and proportional integral derivative (PID). Experimental results show that systems that employ the proposed controllers can quickly achieve the required system performance. Additionally, the PID controller has the best performance, and can improve delay performance by a rate 11. 44% that without the feedback controller. The PI controller is superior to the PD controller. The delay when using the PD is 6. 2% less than that achieved without the feedback controller. [Copyright &y& Elsevier]

Abstract: We present a framework for specification and security analysis of communication protocols for mobile wireless networks. This setting introduces new challenges which are not being addressed by classical protocol analysis techniques. The main complication stems from the fact that the actions of intermediate nodes and their connectivity can no longer be abstracted into a single unstructured adversarial environment as they form an inherent part of the system''s security. In order to model this scenario faithfully, we present a broadcast calculus which makes a clear distinction between the protocol processes and the network''s connectivity graph, which may change independently from protocol actions. We identify a property characterising an important aspect of security in this setting and express it using behavioural equivalences of the calculus. We complement this approach with a control flow analysis which enables us to automatically check this property on a given network and attacker specification. [Copyright &y& Elsevier]

Abstract: The need for reliable data communication performed in critical conditions and the respect of real-time constraints is an open issue in radio-military networks, where fixed and nomadic terminals communicate by means of tactical radio infrastructures. In this perspective the need for real-time constraints plays a fundamental role when the interested applications are remote control, radar traces acquisition and command/control message exchanging. In this paper, the difficulties of data transportation in wireless networks are considered by taking emphasis on the TCP-NewReno implementation that does not guarantee satisfying performance results in such environments. The whole investigation is addressed at designing and validating novel transmission mechanisms to be implemented at the transport layer, directly inherited from standard TCP transmission scheme. TCP-radio and TCP-radio-newRTO proposals are thus discussed and compared with TCP-Westwood+ and TCP-NewReno in order to highlight the necessity for an enhanced transport protocol for data communication performed in radio military environments, where the data transfer is heavily affected by hazardous conditions, such as scattering, shadowing and slow fading. All the tests have been performed through the employment of a network emulator tuned to the radio characteristics in terms of end-to-end delay, available bandwidth and channel modelling. [Copyright &y& Elsevier]

Abstract: With rapid development of wireless technology, more and more applications can be served by wireless networks. To provide integrated service over wireless networks has become a very important issue in the design of wireless networks. In this paper, we propose a new MAC protocol with scheduling algorithms to provide integrated service for CDMA based wireless networks. This protocol evolves from the distributed queuing random access protocol for CDMA wireless network (DQRAP/CDMA). The proposed protocol has been designed to have an ability to accommodate integrated traffic in the network with effective scheduling schemes. A series of simulation experiments have been carried out to evaluate the performance of the proposed protocol and scheduling algorithms. The results reveal that the proposed protocol with the scheduling performs effectively to the integrated traffic composed of messages with or without time constraints and achieves fairness among different types of traffic. [Copyright &y& Elsevier]

Abstract: Years have lapsed since the inauguration of the first Wireless Application Protocol (WAP) application. One of the main reasons for the lukewarm response so far may be attributed to the lack of a “Killer” application. Many companies and developers have attempted to replicate email services (an Internet Killer appplication) within the WAP realm, but till now, no significant success has been reported. This paper will first discuss on the key functions which are lacking in the present WAP-email service, and which are arguably necessary if a much larger user base is to be attracted to these services. A new system will be proposed which can enable the user to send files residing in a remote personal computer (PC) as attachments to his emails using WAP-enabled mobile devices. The implementation of the system will be presented in details. Issue relating to the connection to various types of email servers and the security of the system will also be addressed in the paper. [Copyright &y& Elsevier]

Abstract: Although wireless application protocol (WAP) service acceptance has long attracted considerable interest, the problem of identifying the best theoretical model among the various prevalent models has been relatively neglected. Recently, a few studies have attempted to examine this issue using the decomposed TPB model. It is rare for one model to be superior to all of the other models in all criteria. WAP service acceptance involves competition among three well-established theoretical models, as follows: the Technology Acceptance Model (TAM), the Theory of Planned Behavior (TPB), and the decomposed TPB model. This study compares the effectiveness of these three models in understanding WAP services acceptance. Empirical data were obtained from a field survey in Taiwan. Notable findings were reported for the three competing models, as follows: (1) TPB and decomposed TPB are superior to TAM in terms of their ability to explain user acceptance of WAP services and (2) while the decomposed TPB model provided more easily understood and managerially relevant factors, the TPB model was more parsimonious and had very similar explanatory power to the decomposed TPB model. Finally, the implications of this study are discussed. [Copyright &y& Elsevier]

Abstract: Recently, Zhu et al. proposed a password authenticated key exchange protocol based on RSA. Then, Yeh et al. demonstrated that Zhu et al.''s protocol suffers from the undetectable password-guessing attacks and proposed an improved version. However, there are still some security flaws in Yeh et al.''s proposed protocol. Moreover, the computation load of the wireless device is not light enough. For lightening the computation load, a secure and practical protocol is presented in this paper. [Copyright &y& Elsevier]

Tseng-Jan modified a non-interactive public key distribution system and also proposed several applications based on the Maurer–Yacobi scheme. In their scheme, a user can prove his identity to another user without revealing his secret key. They use a challenge-response-type interactive protocol to achieve their objective. However, in wireless environment, waiting for a corresponding response from the other is time-wasting and consumes the battery of the mobile device. The ability of computing and the capacity of the battery of a mobile device are limited. Therefore, we propose an efficient scheme based on ID-based cryptosystem that is more suitable to be applied in the mobile environment. [Copyright &y& Elsevier]

Modern wireless communication technologies opened up new avenues of data collection from remotely distributed environmental sensors. Global Mobile Communications (GSM) and satellite telephone services currently cover almost all parts of the world. With this development, it became feasible to place and collect data from remote sensors at locations which were previously inaccessible due to distance or extremely restrictive conditions. Although data collection through wireless devices is becoming popular by the day, there is no unified protocol for sending and receiving information from remote devices. In this study, a communication protocol is developed for monitoring a large number of remotely distributed environmental devices. The protocol is being implemented as a part of a project which aims to place a large number of environmental monitoring devices throughout the United Arab Emirates (UAE). [Copyright &y& Elsevier]