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The Internet of Things (IoT) is a system of machines, computing devices, electronic equipment, and different sensors. It forms a network, where the transmission of device-related data can be accomplished. The devices in the IoT are connected to each other through wireless links and form ad-hoc networks. In IoT based applications, the lifetime of the communicating nodes is a greater concern. The network lifetime can be maximized by introducing energy efficient data transmission in the network. Therefore, a traffic and delay-aware energy-efficient routing (TADEER) protocol for IoT-based networks are proposed in this work. The proposed technique assigns delay for transmitting data based on the criticality level of data and traffic rate at the forwarding nodes. Fixing delays for data transmission helps to avoid unnecessary transmissions. The route selection process is implemented using an optimization algorithm. A Fuzzy logic (FL) based biogeography-based optimization (BBO) algorithm is presented in this work. Thus, the number of data transmission and energy consumption can be reduced. The performance of the proposed method is evaluated by analyzing transmission delay, network lifetime, and energy consumption. By comparing the simulation results to the existing methods TEAR and ETASA, the simulation results are validated. [ABSTRACT FROM AUTHOR]

Today's Internet is built on decades-old networking protocols that lack scalability, reliability and security. In response, the networking community has developed path-aware Internet architectures that solve these problems while simultaneously empowering end hosts to exert some control on their packets' route through the network. In these architectures, autonomous systems authorize forwarding paths in accordance with their routing policies, and protect these paths using cryptographic authenticators. For each packet, the sending end host selects an authorized path and embeds it and its authenticators in the packet header. This allows routers to efficiently determine how to forward the packet. The central security property of the data plane, i.e., of forwarding, is that packets can only travel along authorized paths. This property, which we call path authorization, protects the routing policies of autonomous systems from malicious senders. The fundamental role of packet forwarding in the Internet's ecosystem and the complexity of the authentication mechanisms employed call for a formal analysis. We develop IsaNet, a parameterized verification framework for data plane protocols in Isabelle/HOL. We first formulate an abstract model without an attacker for which we prove path authorization. We then refine this model by introducing a Dolev–Yao attacker and by protecting authorized paths using (generic) cryptographic validation fields. This model is parametrized by the path authorization mechanism and assumes five simple verification conditions. We propose novel attacker models and different sets of assumptions on the underlying routing protocol. We validate our framework by instantiating it with nine concrete protocol variants and prove that they each satisfy the verification conditions (and hence path authorization). The invariants needed for the security proof are proven in the parametrized model instead of the instance models. Our framework thus supports low-effort security proofs for data plane protocols. In contrast to what could be achieved with state-of-the-art automated protocol verifiers, our results hold for arbitrary network topologies and sets of authorized paths. [ABSTRACT FROM AUTHOR]

Nowadays, science and technology are developing, more and more things need to be detected by science and technology, and the content that people need to understand is becoming more and more complex. Not only need to know its size, but also need to know some of the relevant comprehensive information or internal information. At present, people's demands can no longer be met only by existing medical systems, so data fusion technology has emerged. This technology can simultaneously obtain a variety of information, express various information, seek the internal relationship between various information, and comprehensively process and improve this relationship. In view of the existing medical equipment, this paper puts forward the design method of multi-sensor data fusion technology. The original whole system is decomposed into several small particles and extracted from the original system. The extracted particles are arranged independently and the neural network system is formed. On the basis of neural network computing and implementing network feature service, this paper introduces how to establish a new medical equipment system based on network registration, discovery and various management and fault-tolerant conditions. This article is a community-oriented, long-distance service intelligent system based on family health care, designed on network processors and Android systems. By combining various technologies, collecting various body information parameters of patients, under the guidance of network protocol and existing remote technology, the gateway of intelligent home can talk to the community to a certain extent. In this way, the data collected in smart homes can be uploaded to other communities through the community network. [ABSTRACT FROM AUTHOR]

Domain name system (DNS) plays a critical part in the functioning of the Internet. But since DNS queries are sent using UDP, it is vulnerable to Distributed Denial of Service (DDoS) attacks. The attacker can take advantage of this and spoof the source IP address and direct the response towards the victim network. And since the network does not keep track of the number of requests going out and responses coming in, the attacker can flood the network with these unwanted DNS responses. Along with DNS, other protocols are also exploited to perform DDoS. Usage of Network Time Protocol (NTP) is to synchronize clocks on systems. Its monlist command replies with 600 entries of previous traffic records. This response is enormous compared to the request. This functionality is used by the attacker in DDoS. Since these attacks can cause colossal congestion, it is crucial to prevent or mitigate these types of attacks. It is obligatory to discover a way to drop the spoofed packets while entering the network to mitigate this type of attack. Intelligent cybersecurity systems are designed for the detection of these attacks. An Intelligent system has AI and ML algorithms to achieve its function. This paper discusses such intelligent method to detect the attack server from legitimate traffic. This method uses an algorithm that gets activated by excess traffic in the network. The excess traffic is determined by the speed or rate of the requests and responses and their ratio. The algorithm extracts the IP addresses of servers and detects which server is sending more packets than requested or which are not requested. This server can be later blocked using a firewall or Access Control List (ACL). [ABSTRACT FROM AUTHOR]

Quick UDP Internet (QUIC) protocol is a transport and application layer solution developed by Google, which is the strong competitor to popular and well established Transmission Control Protocol (TCP). The QUIC protocol is being updated faster resulting into many new versions of the protocol. In this paper, the performance of Modified QUIC (ModQUIC) protocol has been tested with respect to congestion control using India's rapidly growing Internet service provider, the Reliance Jio 4G network (JioFi), which has captured 17% of the market share in a short time. This experimental study investigated ModQUIC protocol performance with congestion control mechanisms CUBIC and Bottleneck Bandwidth Round-trip-propagation-time (BBR) in the JioFi network. The experiment is conducted using a testbed, developed with JioFi and RaspberryPi-3 wireless router along with network emulator: Netem. The ModQUIC performance is verified using test video files stored on Google drive. The performance is tested in packet loss and packet reorder situations using metrics, Throughput and Retransmission Ratio (RTR). We observed that overall ModQUIC/BBR performance is better than ModQUIC/CUBIC in the current Internet. We observed that Reliance Jio is an economical solution for highly populated countries like India, but not a contemporary solution to fulfill India's newly launched digitization project. [ABSTRACT FROM AUTHOR]

With the emergence of cognitive radios, the open spectrum access paradigm that is proposed to overcome the shortcomings of the traditional spectrum allocation paradigm became viable. Researchers have been accumulating efforts to verify the validity of existing networking schemes and protocols as well as designing new ones for this new paradigm. As link failures, due to the activity of primary users, are common in cognitive radio networks, it is essential not to overlook their effect when developing networking solutions including those for multicasting. In this paper, we study the problem of provisioning a multicast session via a tree that has the maximum achievable immunity against any single spectrum failure. The immunity is measured as the minimum percentage of multicast receivers that remain connected with the root of the multicast tree upon the occurrence of a single spectrum failure. The problem is formulated an Integer Linear Program. We also propose a suboptimal algorithm to solve the problem and compare its performance to the optimal performance obtained using the ILP. Results proved the good performance of our algorithm which was always within ≈ 10 % from the optimal solution. Experiments were also conducted to understand how different network parameters affect the achievable immunity. [ABSTRACT FROM AUTHOR]

The computer network security evaluation simulation model is analyzed based on neural network. Firstly, based on the system security experimental platform, the system security detection algorithm is constructed, and the selection strategy of calculation scale is analyzed. The Prefix Span algorithm is introduced, improving its algorithm. Data mining based on Prefix is carried out, with the relationship between intrusions and their relationships analyzed. Secondly, the implementation steps of the algorithm are explained. Finally, the algorithm is tested, and the results are analyzed from three aspects: entropy value feature, active entropy algorithm and cloud platform performance. The conclusion is that the algorithm designed in this paper has good accuracy and adaptability, and it can play a good supporting role in system safety practice training, and the encryption protocol in the network security protocol is further improved, which has laid a solid foundation for the security development of the network. [ABSTRACT FROM AUTHOR]

To optimize energy consumption in wireless sensor networks (WSNs) and prolong life cycle of networks, aiming at the problems in LEACH algorithm, such as random selection of cluster-heads, indeterminate cluster-heads number, accelerated death of cluster-head nodes and so on, an efficient clustering routing algorithm for WSNs (EECR) was proposed. This algorithm is based on LEACH algorithm. In the cluster building stage, four sub-thresholds were designed, i.e. residual energy of node, based on base-station distance, number of cluster-head in networks and round number that nodes are selected as cluster-heads. In stable data transmission stage, the effective path of node was utilized and free spatial model and multi-path attenuation model were integrated to realize effective data transmission. In simulation experiment, the network life, residual energy and information amount received by base station were compared. The results indicate that, compared to LEACH, LEACH-C, HEED and EEUC, the EECR algorithm can effectively reduce energy consumption and prolong network lifetime, and its overall performance is superior to LEACH, LEACH-C, HEED and EEUC algorithms. [ABSTRACT FROM AUTHOR]

Most of the world's power grids are controlled remotely. Their control messages are sent over potentially insecure channels, driving the need for an authentication mechanism. The main communication mechanism for power grids and other utilities is defined by an IEEE standard, referred to as DNP3; this includes the Secure Authentication v5 (SAv5) protocol, which aims to ensure that messages are authenticated. We provide the first security analysis of the complete DNP3: SAv5 protocol. Previous work has considered the message-passing sub-protocol of SAv5 in isolation, and considered some aspects of the intended security properties. In contrast, we formally model and analyse the complex composition of the protocol's sub-protocols. In doing so, we consider the full state machine, the protocol's asymmetric mode, and the possibility of cross-protocol attacks. Furthermore, we model fine-grained security properties that closely match the standard's intended security properties. For our analysis, we leverage the Tamarin prover for the symbolic analysis of security protocols. Our analysis shows that the core DNP3: SAv5 design meets its intended security properties. Notably, we show that a previously reported attack does not apply to the standard. However, our analysis also leads to several concrete recommendations for improving future versions of the standard. [ABSTRACT FROM AUTHOR]

Malfunctions of a mobile ad hoc network (MANET) protocol caused by a conceptual mistake in the protocol design, rather than unreliable communication, can often be detected only by considering communication among the nodes in the network to be reliable. In Restricted Broadcast Process Theory, which was developed for the specification and verification of MANET protocols, the communication operator is lossy. Replacing unreliable with reliable communication invalidates existing results for this process theory. We examine the effects of this adaptation on the semantics of the framework with regard to the non-blocking property of communication in MANETs, the notion of behavioral equivalence relation and its axiomatization. To utilize our complete axiomatization for analyzing the correctness of protocols at the syntactic level, we introduce a precongruence relation which abstracts away from a sequence of multi-hop communications, leading to an application-level action preconditioned by a multi-hop constraint over the topology. We illustrate the applicability of our framework through a simple routing protocol. To prove its correctness, we introduce a novel proof process, based on our precongruence relation. [ABSTRACT FROM AUTHOR]

The evolution of Wireless Sensor Networks has led to the development of protocols that must comply with their new restrictions while being efficient in terms of energy consumption and time. We focus on a collision resolution protocol, the so-called Two Cell Sorted (2CS-WSN). We propose three different ways to improve its performance by minimizing the collision resolution time or the energy consumption. After evaluating these proposals and carrying out the comparison with the original protocol, we recommend an improvement to the protocol which reduces the elapsed time by early 8% and the number of retries and conflicts more than 40%. [ABSTRACT FROM AUTHOR]

In this paper, we propose an energy efficient protocol based on fuzzy logic to not only extend the network lifetime, but also increase the data transmission efficiency in wireless sensor networks. The proposed protocol tries to select the cluster head by considering the current distance and residual energy with the help of fuzzy inference system. Simulation is carried out using OMNeT++ to demonstrate that the proposed protocol performs better than the other existing ones in terms of energy consumption, network lifetime and number of packets received by the sink node. [ABSTRACT FROM AUTHOR]

In order to solve the contradiction between wireless network application requirements and increasingly scarce spectrum resources, cognitive wireless network technology emerged. Based on the characteristics of wireless network nodes and combining multiple hybrid control strategies, this paper proposes a multi-priority dual-clock probability detection CSMA(MPDCPD-CSMA) protocol with a monitoring mechanism. The field-programmable gate array (FPGA) hardware circuit is used as an experimental research platform for the first time. Cognitive wireless network MAC protocol design and implementation. The design took full advantage of the flexibility of the FPGA, using a hardware description language Verilog HDL and schematic input combined with the QuartusII9.0 circuit design. By comparing the statistical values of the circuit system with the theoretical values, it is verified that the design has the characteristics of good real-time performance, high reliability, and strong portability. It can effectively reduce system node energy consumption, improve system throughput, and can be applied to wireless networks. [ABSTRACT FROM AUTHOR]

With the advancements in cognitive radio network procedures, such as blind sensing, sensing transmission trade-off, energy aware protocols etc, effectively overcomes the power constraint issues of CBAN. In present work, such primary issues have been addressed with the help of look-up table incorporated with energy harvesting (EH). It delivers maximum achievable throughput with minimum energy consumption to obtain self-sustainable pervasive wireless networks. The experimental work has been carried out in three different scenarios (Echelon 1, 2 and 3). The key components such as look-up table and energy harvesting have also been investigated on different system parameters (like energy consumption, normalized throughput, saved and residual energy). The simulation is done with NS-2 and results are shown in Matlab for clarity. Results depict that proposed model consumes less energy and also provides a better normalised achievable throughput as compared to the conventional model. [ABSTRACT FROM AUTHOR]

We present the JaCaMo+ framework for programming multiagent systems (MAS), where agents interact thanks to commitment-based interaction protocols. Commitment protocols are realized as artifacts that maintain a social state and notify to the participating agents those events that are relevant to the interaction. We discuss the advantages, like increased modularity and flexibility, that are brought by commitment-ruled interactions with respect to other proposals. We trace back such advantages to the possibility of relying on a standardized commitment lifecycle. We explain how to use the framework to program interacting agents by using the Netbill protocol as running example, and the Gold Miners scenario as a more complex programming example. [ABSTRACT FROM AUTHOR]

IEEE 802.22 Wireless Regional Area Network (WRAN) standard employs cognitive radio techniques to utilize the white (i.e., unused) spectrum in the TV frequency band. IEEE 802.22 WRAN employs cellular topology (i.e., point to multi-point communications). IEEE 802.22b is a modified version of IEEE 802.22 that allows peer-to-peer communications among WRAN users of the same cell. One of the issues that significantly affects the performance of WRAN is the spectrum sharing between overlapped WRAN cells (i.e., inter spectrum sharing) as well as among the users of the same cell (i.e., intra spectrum sharing). In this paper, we propose Resource Sharing Protocol for Inter/Intra WRAN communications (RSP-WRAN), which is based on maximizing the Jain's fairness index in the spectrum-sharing process. Simulation results show that RSP-WRAN, compared to other protocols, achieves high performance in terms of fairness and network throughput. [ABSTRACT FROM AUTHOR]

For disaster recovery, we store backups of a file in several positions far away from each other. If we delegate this task to an untrusted cloud service provider, a verification method is desired. In this paper, we construct a generic transformation from "proof of retrievability" to "proof of multicopy". We present this work in two stages. In the first stage, we propose a generic protocol of "proof of file position" based on an arbitrary secure "proof of retrievability" protocol. In the second stage, we propose a "proof of multicopy" protocol based on our "proof of file position" protocol. Both of our protocols are provably secure. [ABSTRACT FROM AUTHOR]

Recently how to audit cloud storage correctly and securely is a very hot research topic for cloud storage. At Infocom 2015, Chen et al. proposed a novel secure cloud storage audit protocol based on distributed string equality checking, which is a very interesting result. In this paper, we give some improvements to their protocol to strengthen its security. In particular, we show that if the data owners reuse pseudorandom function on the same order number of file block when uploading file block's tag to the cloud, the protocol maybe not secure any more. We also show that there can exist P many (mi, ci) pairs which will result in the same inner product sum n ∑ni=1 mi . ci while mi denotes the file block, ci denotes the challenge value, and n denotes the number of blocks. We emphasis here that the flaw maybe does not lie in the traditional security model of cloud storage auditing protocol, but we think it is actually a serious drawback for current secure cloud storage audit protocols. We emphasis these two flaws can also exist in some famous cloud auditing protocols such as PDP and POR. Finally, we give an improvement to their protocol, and thus also give a way to strengthen the famous PDP and POR protocols. [ABSTRACT FROM AUTHOR]

Two-factor authenticated key exchange (TFAKE) protocols are critical tools for ensuring identity authentication and secure data transmission for cloud computing. Until now, numerous TFAKE protocols based on smart cards and passwords are proposed under this circumstance. Unfortunately, most of them are found insecure against various attacks. Researchers focus on cryptanalysis of these protocols and then fixing the loopholes. Little attention has been paid to design rationales and formal security models of these protocols. In this paper, we summarize the security requirements and put forward a formal security model for TFAKE protocols for cloud computing. We then present an efficient TFAKE protocol without using expensive asymmetric cryptology mechanisms to achieve high efficiency. Our protocol can be proven secure in the random oracle model and achieves user anonymity. Compared with other TFAKE protocols, our protocol is more efficient and enjoys provable security. [ABSTRACT FROM AUTHOR]

With the widespread use of real-time applications (VoIP, IPTV, Video conference, etc.) in Internet, protection and resource optimization become increasingly desired. Network protection aims to decrease the interruption time of communications by precomputing backup paths capable to receive and route traffics of affected primary paths upon failures. Resource optimization is achieved by improving data routing and resource sharing: data routing is often optimized by following the shortest paths whereas resource sharing is applied between the backup paths protecting against different failure risks. Two strategies of resource sharing are defined in literature: (1) backup sharing which limits the resource sharing to the backup paths and (2) global sharing which extends the resource sharing to the primary and backup paths. In this paper, we compared the effects of resource sharing strategies on the resource utilization when the primary paths correspond to the shortest ones according to a static metric. With the single failure assumption, we show formally that the resource sharing between primary and backup paths is limited to some few links which cannot form a backup path. Thus, independently of the amount of resources (for instance: bandwidth) that can be shared between the primary and backup paths, the maximum number of backup paths is bounded. In our simulation, we comfort our formal result by showing that the two strategies have close acceptance rates of backup paths and protection bandwidth utilizations. [ABSTRACT FROM AUTHOR]

Freight transport has a high relevance in the transportation domain. Regulations regarding driving times and rest periods are very restrictive to ensure road safety. Truck drivers need to know the parking availability in road rest areas in order to achieve their destination respecting laws and contributing to road safety, and at the same time, to a sustainable trip. This paper proposes a novel protocol based on cascade negotiations among trucks and rest areas to help drivers in the selection of areas to park for these long journeys. The cascade negotiations are driven according to the parking preferences for each truck involved and the features of the road network. The goal pursued in these negotiations is to minimize the number of trucks that have to park illegally and maximize the satisfaction of drivers with respect to their individual parking preferences. The novel protocol is a combination of a reservation system with a voting-based negotiation. This proposal has been implemented in a Multi-Agent based simulation model. A real road section, the European E-15 road, has been modeled in the MAS using real traffic data. Results show that illegal parking is reduced with respect to a situation without negotiation just following a first-come first-served basis for trucks parking in specific areas. The global satisfaction is enhanced when the protocol results are compared to an approach without negotiation or with a centralized version of the protocol. [ABSTRACT FROM AUTHOR]

For a thorough understanding of procedures in various network applications, and to automatically classify, recognize, trace, and control them, it is necessary that the state machine representing application sessions is obtained in advance. This article presents a novel approach to reversely infer a protocol state machine from collected data of the application layer. Protocol state machines are derived using a method of error-correcting grammatical inference, which is based on symbol sequences that appear in the application sessions. The techniques are implemented into a tool called PREUGI, which is conducted in a real network, containing a number of real applications with several application layer protocols, to validate the proposed method. [ABSTRACT FROM AUTHOR]

An efficient protocol for establishing secret keys for neighboring nodes in a wireless network is presented in this paper. The security of the key generated by our protocol is based on the unpredictability of the noises in binary symmetric communication channels. The two nodes which try to establish a common secret key receive messages from a common source of random bit strings. Due to noises in the communication channel, the messages received by them, and most importantly the messages received by the eavesdropper, are not the same. We show that the two nodes can modify their messages in an efficient way to obtain a common string which contains enough uncertainty to the eavesdropper. Then, a secure universal hash function is applied to compute a secret key for extracting randomness from the common string. We prove that the probability for the eavesdropper to know the value of the key is negligible. One advantage of our proposed protocol is that the secret key rate is better than the known scheme in other models, such as the bounded storage model. Furthermore, our proposed protocol needs only to perform exclusive-or operations and compute hash values. Thus, it is a computationally light-weight protocol and suitable for devices with limited computing resources, such as sensors in sensor networks. [ABSTRACT FROM AUTHOR]

With the increasingly expanding application of RFID technology, the security and privacy issues of RFID system has also been a widespread concern. The existing RFID security protocol can't simultaneously meet the requirements of low-cost, low computing, high efficiency and high security. In this paper, through the analysis of common principles and shortcomings of RFID security protocols based on Hash Function, we improve the security protocols, so as to achieve the objectives of two-way authentication. This paper theoretically proves the protocol security through BAN logic. And the new protocols can effectively solve the security and privacy problems such as replay attack, fake attack, location privacy, anonymous tags and so on. The paper proposes a kind of authentication and communication security mechanism that makes full use of the functions of the conditional Access Module (CAM) which exist in the original remote education system and when authenticating the nodes of the system, we use the proposed security scheme. Analysis showed that the mechanism is safe, reliable, strong compatibility, economic and applicable. [ABSTRACT FROM AUTHOR]

In telecommunications, the capture effect is a phenomenon associated with frequency modulation reception in which two strong signals at, or near, the same frequency or channel will be demodulated. In wireless networks, a frame collision does not necessarily result in all the simultaneously transmitted frames being lost. Depending on the relative signal power and the arrival time of the involved frames, one frame can survive the collision and be successfully received by the receiver. Efficient object identification with passive RFID tags. In former works, many researches focus on the RFID anticollision protocol only, however, less did pay special attention to the capture effect mainly to keep the design simple and cost low. Nonetheless, the capture effect occurs frequently in real deployments. In this paper, we have taken the capture effect into consideration and combined this thought to an efficient RFID anti-collision protocol, then proposed an efficient method to estimate the optimal frame length to adjust the quantity of RFID tags. After setting an optimal frame length by using the proposed method, furthermore, we obtained higher identification efficiency. RFID technology can be used for real-time recording and tracking of the learning process, which comprises real-time records of learners and their partners learning process such as experience, debate, cooperation, competition, problem solving, and other learning experiences. [ABSTRACT FROM AUTHOR]

The wireless sensor networking (WSN) systems have been used for several applications from target tracking to environment monitoring. Recently, there has been increased interest in the design of WSN protocols for delay-sensitive applications, such as military surveillance, health monitoring, and infrastructure security. In this paper, we apply gene regulatory networks (GRN) principles to the WSN system and analyze a reaction-diffusion mechanisms for decentralized node scheduling design. Using control theory, we verify that the proposed scheme guarantees system stability. Also, we provide conditions of system parameters to ensure system convergence and stability. Simulation results indicate that the proposed scheme achieves superior performance with energy balancing as well as desirable delay compared with other wellknown schemes. [ABSTRACT FROM AUTHOR]

Security APIs, key servers and protocols that need to keep the status of transactions, require to maintain a global, non-monotonic state, e.g., in the form of a database or register. However, most existing automated verification tools do not support the analysis of such stateful security protocols - sometimes because of fundamental reasons, such as the encoding of the protocol as Horn clauses, which are inherently monotonic. A notable exception is the recent tamarin prover which allows specifying protocols as multiset rewrite (msr) rules, a formalism expressive enough to encode state. As multiset rewriting is a "low-level" specification language with no direct support for concurrent message passing, encoding protocols correctly is a difficult and error-prone process. We propose a process calculus which is a variant of the applied pi calculus with constructs for manipulation of a global state by processes running in parallel. We show that this language can be translated to msr rules whilst preserving all security properties expressible in a dedicated first-order logic for security properties. The translation has been implemented in a prototype tool which uses the tamarin prover as a backend. We apply the tool to several case studies among which a simplified fragment of PKCS#11, the Yubikey security token, and an optimistic contract signing protocol. [ABSTRACT FROM AUTHOR]

Contract Net Protocol (CNP) is probably the most widely used task allocation protocol in distributed multi-agent systems (MAS). To cope with real-world applications, this protocol must be expanded by addressing some major challenging issues in the current distributed systems. Temporal interaction aspects and reliability issues of such systems, critical to guaranteeing performance, are the focus of this paper. Many researchers have proposed various methods to expand and to improve CNP but those challenges have not been much addressed in a formal way. To cope with these limitations, this paper proposes a Petri net-based model that extends the conventional contract net with real time constraints, often defined as interaction duration and message deadlines, and fault tolerance to handle the agent death exception. Our aim is, hence, to devise an extended CNP that achieves the reliability of the manager agent in the case of contractor crash failure while operating in an open and large scale multi-agent system under time constraints. To address the challenge problem of crash failure detection of the contractor in CNP, we propose to formally model the watchdog/heartbeat mechanism into the communication between the manager and the contractor. Using such mechanism, the manager can detect the crash failure on time and may hence trigger an appropriate recovery procedure to move the system into a safe and a consistent state. The proposed extended CNP model is developed using stochastic timed colored Petri nets which include systematic specification, design and implementation of components of the system. Various useful results will be drawn by simulation as well as state space analysis. This formal analysis shows that the protocol terminates correctly either in a safety case or in a failure situation. It also proves that the protocol meets the key properties namely model correctness, deadline respect, absence of deadlocks and livelocks, absence of dead code, agent terminal states consistency, concurrency, and validity. [ABSTRACT FROM AUTHOR]

Substream-based P2P live streaming systems can achieve high performance according to multiple metrics, including distribution delay, system robustness and protocol overhead. However, the current division approach into substreams is not flexible and cannot be adaptive to dynamic network environments, which characterize the basic transport facilities for supporting P2P live streaming services. In this paper, we propose a virtual adaptive substream partition and scheduling protocol, namely VAStream, which can enforce substream partition or merge operation based on the current P2P network status. This protocol also presents properly crafted schemes to deal with the issues in complex network situation, and effectively makes use of peer resources. Comparing with other mechanisms, the simulation results show that VAStream can achieve low distribution delay, high chunk arrival ratio and good system robustness. [ABSTRACT FROM AUTHOR]

Garbled circuits provide a powerful tool for jointly evaluating functions while preserving the privacy of each user's inputs. While recent research has made the use of this primitive more practical, such solutions generally assume that participants are symmetrically provisioned with massive computing resources. In reality, most people on the planet only have access to the comparatively sparse computational resources associated with their mobile phones, and those willing and able to pay for access to public cloud computing infrastructure cannot be assured that their data will remain unexposed. We address this problem by creating a new SFE protocol that allows mobile devices to securely outsource the majority of computation required to evaluate a garbled circuit. Our protocol, which builds on the most efficient garbled circuit evaluation techniques, includes a new outsourced oblivious transfer primitive that requires significantly less bandwidth and computation than standard OT primitives and outsourced input validation techniques that force the cloud to prove that it is executing all protocols correctly. After showing that our extensions are secure in the malicious model, we conduct an extensive performance evaluation for a number of standard SFE test applications as well as a privacy-preserving navigation application designed specifically for the mobile use-case. Our system reduces execution time by 98.92% and bandwidth by 99.95% for the edit distance problem of size 128 compared to non-outsourced evaluation. These results show that even the least capable devices are capable of using large garbled circuits for secure computation. [ABSTRACT FROM AUTHOR]

A Cloud Computing system must readjust its resources by taking into account the demand for its services. This raises the need for designing protocols that provide the individual components of the Cloud architecture with the ability to self-adapt and to reach agreements in order to deal with changes in the services demand. Furthermore, if the Cloud provider has signed a Service Level Agreement with the clients of the services that it offers, the appropriate agreement mechanism has to ensure the provision of the service contracted within a specified time. This paper introduces real-time mechanisms for the agreement and fulfilment of SLAs in Cloud Computing environments. On the one hand, it presents a negotiation protocol inspired by the standard WS-Agreement used in web services to manage the interactions between the client and the Cloud provider to agree the terms of the SLA of a service. On the other hand, it proposes the application of a real-time argumentation framework for redistributing resources and ensuring the fulfilment of these SLAs during peaks in the service demand. [ABSTRACT FROM AUTHOR]

Rational computation means secure multi-party computation in the presence of rational parties, who care about maximizing their utility. Here the notion of utility denotes payoffs when parties take certain actions in the computation. Therefore rational parties may carefully choose their actions before they interact with others. Traditionally, the main tasks of rational computation is to encourage parties to exchange information with their opponents, even if they do not trust each other. Exchanging information is similar to the action of cooperation towards the view of game theory. Therefore, measures should be taken to encourage parties to cooperate with others in rational computation. In this paper, we assume that rational parties who participate in the computation protocol form a social cloud. Parties in the social cloud may interact within several rounds and in each round, some desirable properties such as reputation may be generated. Parties who have good reputation means they are likely to cooperate with others. The structure of social cloud is not static. Instead, it evolutes when parties complete one round of computation. We mainly discuss the impact of social cloud structure on rational computation. Simulation results show that when the community structure reach to a proper value, parties are more likely to cooperate in the computation protocol. In addition, rational parties can gain optimal utilities. [ABSTRACT FROM AUTHOR]

Delay-sensitive applications require the capability to send data while meeting performance requirements. However, due to strict constrains on the resources available to the sensor nodes, wireless sensor networks (WSNs) pose critical challenges in network protocol design considering delay constraints. Biologically inspired modeling techniques have received considerable attention for achieving robust global behavior, while retaining individual simplicity. In this paper, we propose an epidemic-inspired node scheduling scheme (ENS) with aims of delay reduction and energy saving. The ENS controls the state of a sensor node depending on the delay requirements of a specific application. Simulation results indicate that the ENS achieves reliable data delivery while saving energy consumption. [ABSTRACT FROM AUTHOR]

This paper describes a fieldbus of which the physical layer using CAN (Controller Area Network) transmission line and the data link layer using SPI (Serial Peripheral Interface) interface protocol. It applies to the two-way information exchange between the controller (master) and the sensor/actuator (slave), to build the underlying network monitoring system. The bus takes the advantage of the electrical characteristics of CAN transmission line, and the bus inherits its anti-interference ability and the advantage of long transmission distance. Also, it inherits the merits of SPI bus communication such as fast, easy to use and low cost. Compared with the half duplex distributed network constructed by EIA-485, the slave in this bus is a pure hardware device, saving the MCU chip and software programming. This paper presents a new bus communication protocols and hardware structure of slave interface module and describes the working principle of the interface circuit. Finally, experimental data and test results are given, verifying the feasibility and communication features of this type of bus and the interface module design. [ABSTRACT FROM AUTHOR]

For establishing communications and modeling a framework for dialogue between intelligent agents, it is beneficial to have a well-defined strategy. In a dialogue run, the strategies are the manners to achieve the agents' goals by selecting the best option between the different existent choices. There are not many works which define the strategies for dialogue between agents. In this paper a formal model for dialogue strategy is proposed. The proposed model is a decision making problem of selecting the type of the act and the compatible content to utter at each step of a dialogue. In a given dialogue step, the model can decide the appropriate act and content allowed by the dialogue protocol in order to satisfy the agents' goals. The strength of the decisions which define the best next move is computed by argumentation theory. The proposed model is illustrated through an example of Dutch auction. [ABSTRACT FROM AUTHOR]

In order for automated agent-based e-Commerce transactions to blossom, well-defined, analyzable and easily customizable interaction protocols or choreographies of involved parties need to be developed. Although, several domain-depended protocols have already been developed, efficient methodologies and technologies for facilitating the definition, deployment, reuse and maintenance of interaction protocols should be developed. This paper proposes a rule-based, reusable, analyzable and easily comprehensible by the user choreography definition methodology, called K-SWAN. Ôhe proposed choreography scheme separates the definition of the agent shared interaction protocol from the private agent interaction strategy and enables agents to choose the appropriate protocol for the transaction, from a library of re-usable interaction protocols, and automatically combine it with their personal strategy, from a private library, by using SW technologies for both. Complying with K-SWAN methodology will let agents participate seamlessly in different interaction processes and/or modify their behavior with a minimal programming effort. Finally, this paper presents the integration of the K-SWAN methodology into EMERALD, a multi-agent knowledge-based framework based on SW standards, which maximizes reusability and interoperability of behavior between agents. [ABSTRACT FROM AUTHOR]