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Aiming at the high complexity of regression algorithms, the lack of unified classification standards and public data sets in the link quality estimation model of wireless sensor network, this paper proposed a link quality estimation method ELRLQE ( EWMA and linear regression based link quality estimation ) based on EWMA and linear regression. Taking RSSI, LQI and SNR acquired from the physical layer, as well as PRR ( packet reception ratio) as input metrics, it collected data in various experimental environments with different transmission power, contending conditions and deployment methods, and established a link quality estimation data set. It preprocessed the data by minimum interpolation and EWMA, which significantly improved the correlation between the input features of the regression model and the link quality. Compared with the existing methods, ELR-LQE is more adaptable to the network layer protocols, with lower complexity, thereby more suitable for implementation in wireless sensor network nodes with limited resources. The experimental results show that ELR-LQE has a high accuracy. Under a variety of experimental conditions, the average ME is 4.6 x 10-2 and R² is 0.99. [ABSTRACT FROM AUTHOR]

A coarse cereal is one of the most important crops rich in nutrients. However, the frequently-occurred issues on food quality and safety have seriously endangered the trust in recent years, for example, the abuse of chemicals, heavy metals exceeding the standard, and harmful germs. Therefore, a traceability system is an urgent need for coarse cereals, in order to bridge the trust between farms and consumers, where the source of agricultural coarse foods can be rapidly traced through multi-party efficient collaboration. Most current traceability systems focus on recording data using bar or QR codes, radio frequency identification, and wireless sensor networks. But the tracing information is broken easily between upstream and downstream, leading to the blur transferred data, particularly on the long and scattered supply-chain of agricultural foods, including cultivation, processing, logistics, storage, and sales. Furthermore, the traditional traceability system cannot efficiently supervise the data records of each company, when quality and safety issues occur. As such, it is impossible to recall the problematic foods in time, much less to accurately locate the responsible party. Fortunately, blockchain technology can be utilized to integrate the distributed architecture, storage, and verification in the block, peer-to-peer network protocols, encryption, consensus mechanisms, identity authentication, and smart contracts. The data disclosure can also be used to enhance trust with fewer intermediate links. Therefore, this study aims to deal with the long supply-chain of coarse cereals, many trace entities, the differentiate share of data ledger, and the real-time monitoring of on-chain data. A novel traceability system was designed to implement the supervisable food products using the multi-chain architecture of blockchain and supply chain in coarse cereal. The forward and reverse traceability data was also collected ranging from the planting, processing, warehousing, transportation, and sales, using cameras, sensors, Beidou positioning devices, and IoT devices in real-time. Moreover, a systematic investigation was made on the business process and supervision characteristics of the supply-chain, as well as the full life cycle of coarse cereal. In addition, a new architecture of supervision-oriented multi-chain data storage was proposed for the actual production of coarse cereal. Specifically, the off-chain CouchDB state database was selected to store the key-value traceability data, particularly on the key-index instead of traversal query to improve the query efficiency. More importantly, a network access mechanism was designed using the regulatory authority, further to realize the collaborative supervision on- and off-chain through smart contracts. Correspondingly, blockchain technology was used to ensure the deep connection of various production factor resources with the real economy of coarse cereal. Anyway, the supply chain of coarse cereal integrated with the blockchain was utilized to strengthen the multi-party collaboration through mutual identity authentication, especially on data expansion, data sharing, and supervision. In terms of security, the average change rate of ciphertext in the enterprise network authorization diffusivity test was 82.53%, the average change rate of ciphertext in the enterprise network authorization correlation test was 82.39%, indicating higher security and less confusion. In terms of efficiency, the average time for consumers to query public traceability data was 0.415 s, and the average time for regulators to call cross-link port to query enterprise sensitive traceability data was 0.871 s. Furthermore, an actual traceability system was implemented to verify the model using Hyperledger Fabric for data privacy protection, data differentiation sharing, and the penetration supervision of traceability data, together with the real-time management, and control of traceability nodes. The in-depth mining was realized for the value of coarse cereal traceability big data, and sustainable development of the traced network. As such, farmers can receive professional or industrial policy guidance, whereas, companies can obtain the market trends and price conditions in real-time, and regulatory authorities can accurately control traceability data and transaction behavior. The finding can greatly improve the quality and safety of coarse cereal, production efficiency, and economic benefits. [ABSTRACT FROM AUTHOR]

By the reading of the source code and the official documents, this paper analyzed P2P protocols of three main blockchain systems, included Bitcoin, Ethereum and hyperledger fabric, discussed the changes in the evolution process of the P2P protocol of blockchain in detail, and analyzed the advantages and disadvantages of different protocols. This paper put forward an analysis standard and a quantitative evaluation, to offer a useful inspiration and guidance for the research of blockchain network protocols in future . [ABSTRACT FROM AUTHOR]

For the cloud service combination request from cloud consumers, the paper used the agent method and an extended contract net protocol to build a service capacity table of agent and designed a cloud service combination interaction model based on agent which was verified by simulation experiments. Experimental results show that the proposed method has higher success rate of cloud service combination than ant colony algorithm and simulated annealing genetic algorithm. [ABSTRACT FROM AUTHOR]

A large number of single-packet flows reduce the efficiency of flow identification. It is important to explore a filtering mechanism for single-packet flows so as to improve the efficiency of flow identification. This paper proposed a probability-guaranteed filtering mechanism for TCP single-packet flows based on flow characteristics and TCP protocol specifications. The results of a lot of experiments based on Traces collected from a main channel in the CERNET and spanned two years show this mechanism can improve the efficiency of flow identification substantially at the cost of little loss of accuracy. Relative to the existing filtering strategies, this mechanism improves the performance and stability greatly. [ABSTRACT FROM AUTHOR]

In order to improve efficiency flaws of TLS protocol such as frequent interaction times and high computation overload, through the analysis and research on the protocol, this paper proposed a new ECC-based protocol in which RSA was substituted by ECC. It improved the new protocol performance. Through cache handshake parameters, the number of shake hands interaction was less. It used SVO logic to analyze ECC-based protocol, and the result shows that it is secure. The simulation experiment and comparison with original protocol show that with the increased level of security, the new ECC-based protocol is more predominant. [ABSTRACT FROM AUTHOR]

Idle-listening is the key factor for energy-efficiency and longevity of multi-hop wireless sensor network (WSN) deployments. While existing coordinated sleep/wakeup scheduling protocols eliminate idle-listening for simple traffic patterns, they are unsuitable to handle idle-listening by producing the complex traffic patterns of the random routing protocols. This paper presented a MAC protocol based on pseudo-random (MAC-PR), which avoided the overhead of distributing complex, large sleep/wakeup scheduling information to the nodes. MAC-PR piggybacks onto the relayed data packets the seed of the pseudorandom generator that encoded the scheduling information, and enabled any recipient/snooper to calculate its sleep/wakeup schedule from this seed. In addition, MAC-PR trades off doing extra computation in order to avoid expensive control packet transmission cost. It shows through simulations and real implementation on TelosB motes that MAC-PR eliminates the idle-listening problem, and makes the transmissions of data packets based on random routing protocol having those characteristics of self-stabilizing, low-latency, and low-cost relaying. [ABSTRACT FROM AUTHOR]

Considering that the priority of data services is not distinguished in the existing multi-channel MAC layer protocols in wireless sensor networks, this paper proposed a protocol of DP-McMAC. This protocol employed priority scheduling strategy and different service mechanisms by setting different back-off parameters and competition windows for data services with different priorities. This paper gave a mathematical modeling and delay analysis about the protocol. Simulation results indicate that the proposed protocol performs better than existence protocols in delay and throughput when the high-priority data come to, it ensures real-time requirements of the transmission. [ABSTRACT FROM AUTHOR]

To enhance the dynamic adaptability of wireless sensor networks and achieve optimal packet transmission, this paper designed a collection tree protocol algorithm based routing protocol by NesC programming language based on TinyOS 2. x operating system called ICTP. The protocol used transmitted expectations to guide routing packets and transmit data packet, and considered the residual energy of in the next-hop neighbor nodes in order to achieve dynamic equilibrium of network energy consumption in data packet transmission process. TOSSIM simulation results show that the improved ICTP routing protocol can effectively reduce the transmission delay, prolong network lifetime and improve network efficiency. [ABSTRACT FROM AUTHOR]

Aiming at the problem that IEEE 802. 15. 4 MAC protocols in wireless sensor networks had high delivery latency,an improved low-delay MAC mechanism LD-MAC based on the existing LE-MAC protocol was proposed. The protocol reduced the delivery latency by improving the number of CCA. When the backoff counter reached zero, the node performed carrier sensing that consisted of clear channel assessment (CCA) for the next CW consecutive backoff slots. If the channel was sensed idle during the first CCA,the node tansmitd the data directly. The properties of the improved mechanism were analyzed theoretically by using two-dimensional Markov chain model. The simulation results showed that LD-MAC not only reduced the delivery latency but also improved the throughput significantly by only increasing energy consumption slightly. [ABSTRACT FROM AUTHOR]

Aiming at the questions that the campus integrated service platform developing in traditional way was difficult to maintain, and extend and the user experience was not good enough, a developing scheme integrated SSH2 and jQuery was proposed using MyEclipse 8. 5 as development tool and MySQL. In this scheme, view layer was implemented by the JSP and jQuery framework, business logic layer was implemented by Struts2 and Spring framework, data persistence layer was implemented by Hibernate and Spring Framework. The results showed that the scheme improved the efficiency of the system, enhanced the maintainability and scalability of the system and the user experience. [ABSTRACT FROM AUTHOR]

In order to precaution known and unknown attack of RFID technology, this paper proposed multi-decision tree model based on the analysis of RFID security protocol to check the intrusion behavior. By the analysis of the multi-decision tree model, the model can find the relationship of different attack of RFID technology. And the model has the advantage of extensibility and high efficiency, which make the multi-decision tree model suitable for all practical application of RFID system. [ABSTRACT FROM AUTHOR]

This paper proposed a data collection protocol (MULAC) to maximize the lifetime of WSN. Firstly, it selected a sensor v that its distance to the user less than r. Secondly, it took v as the root to construct a maximum lifetime tree T. All sensors could send its data to the virtual sink through T. Last, the user could get all data of WSN by virtual sink. When the user moved to another location, the root of tree will change. It is NP-hard to adjust the structure of routing tree with minimum energy. MULAC algorithm could quasi-optimal solve this problem. Simulation results make clear that MULAC can effectively prolong the life of WSN. [ABSTRACT FROM AUTHOR]

This paper proposed a protocol for ancilla-driven universal blind quantum computation by incorporating the idea of quantum teleportation model to computation named as "universal blind quantum computation" by Broadbent et al. In addition, it used compute register's operate on quantum entanglement to replace the measurement of the quantum bit. Because the latter was limited to two qubits' measurement, the former had an obvious advantage. Based on these improvements it designed a protocol to achieve ancilla-driven universal blind quantum computation. This protocol could regarded as a blind version of "ancilla-driven universal quantum computation" due to Anders et al, improve its computing ability, and ensure the compute correctness, so that any party involved in this computation cannot get the other party's privacy information. [ABSTRACT FROM AUTHOR]

This paper firstly introduced the function and meaning of cooperative communication, and then divided cooperative communication into several types according coordination level, and respectively reviewed and compared main and typical protocols in each type in terms of main network performance. Lastly it proposed some problems which were worth further studying in cooperative communication area. [ABSTRACT FROM AUTHOR]

Compared with the terrestrial wireless sensor networks, underwater sensor network has a longer propagation delay. Thus, the existing MAC protocols for wireless sensor network can not be directly applied in underwater environment. This paper proposed a channel reservation multiple access protocol based on compressed sensing ( CS) in underwater sensor networks. The novel scheme made full use of the long propagation delay in the underwater environment, in order that each node could share the channel resource in both time and space dimension. By virtue of the newly arisen CS theory, the scheme achieved simultaneously channel reservation for multiple users and improved channel utilization of the underwater sensor networks. By taking multiuser diversity into consideration, it admitted the best users whose channel access requests to take advantage of the limited bandwidth for high-speed transmission, leading to an improved system throughput for the entire network. Simulation results show that, compared to the traditional RTS/CTS scheme, the proposed protocol has higher channel reservation capability, higher data transmission efficiency, and best throughput performance. [ABSTRACT FROM AUTHOR]

In order to quickly and effectively identify the application-layer DoS attacks, this paper presented a detection method based on HMM. In this method, the input was the application-layer protocol's keywords and their inter-arrival times. Then, it used the hidden Markov model to detect application-layer DoS attacks. The experimental results show that the proposed method is valid to discover several different application-layer DoS attacks with relatively high detection ratio and low false positive ratio. [ABSTRACT FROM AUTHOR]

This paper proposed a secure communication model for space delay-tolerant network. This model applied predicate logic, and built SDTN directed multi-path graph, security protocol service set, reliable path selection service set, and forwarding capacity set. It also gave out the model's security constraint rule and secure communication algorithm. It defined the state machine of space delay-tolerant network secure communication, and proved the model's security, reliability and delay-tolerant ability, which laid the foundation for space delay-tolerant network secure communication. [ABSTRACT FROM AUTHOR]

In order to improve the performance in high-speed sensor networks which traffic load was high and flow changes dramatically, this paper studied backoff algorithm of competitive MAC protocol, and based on BDQR proposed a backoff algorithm of MAC protocol with flow predicted and quality of service distinguished. The algorithm introduced a traffic predictor to accurately predict traffic and dynamically adapted the window; introduced priority factor to achieve the distinction of quality of service, to meet the real-time requirements of critical data; used energy consumption factor for adaptive channel access probability, to balance energy consumption and extend the life cycle of the overall network. The NS2 simulation results show that the network performance of FPQoSD backoff algorithm in the nodes of high-density and high-load environment is superior. The throughput is higher than BDQR algorithm by 15%, average delay decreases by 25%, average energy consumption decreases by 10%, and overall life cycle is lengthened. [ABSTRACT FROM AUTHOR]

Thia paper firstly analyzed the basic principles of UDP-based improved protocols, and then elaborated the design ideas of these improved protocols proposed in recent years. By establishing end-to-end test bed, it evaluated the effect of RTT and loss rate to the four typical improved protocols (RBUDP, Tsunami, UDT, and PA-UDP). The experimental results show the throughput of the four improved protocols decreases with RTT and loss rate increasing. Finally this paper proposed some further research directions. [ABSTRACT FROM AUTHOR]

To improve performance of wireless sensor networks in terms of energy consumption, network latency and traffic adaption, this paper proposed LCT-MAC with collision avoidance and traffic adaption through analyzing some classic MAC protocols. This protocol divided the long preamble into lots of small ones embedded with destination address to avoid crosstalk, and adjusted nodes sleep cycle according to traffic loads dynamically, and chose proper backoff time to avoid message collisions on the basis of nodes' priority. Simulations demonstrate that LCT-MAC is superior to both S-MAC and LPL in aspects of network latency, energy consumption as well as message collision, and has a good performance. [ABSTRACT FROM AUTHOR]

To address the problem that existing legacy Web application systems using HTTP authentication protocols cannot be modified in implementing SSO technology, this paper proposed a transparent SSO integration technology which required no modifications to the existing legacy systems. The proposed technology employed a plug-in module which inserted into the HTTP request and response processing pipelines of a Web server. The plug-in automatically processed the reciprocal exchanges of authentication data with the Web server employing a HTTP authentication protocol. As a result, it achieved SSO without the changes or modifications to the Web server and application. Practical applications and tests demonstrate that the proposed technology has achieved the predined functionality and the expected effects. The technology is highly helpful to the implementations of SSO. [ABSTRACT FROM AUTHOR]

In order to overcome the shortcomings of traditional EJB, CORBA, and publish/subscribe middleware software architecture, an efficient software component framework suitable for embedded distributed computing environment is proposed. The software architecture is based on the open service gateway initiative ( OSGi) standard, and can be used in multi-communications protocol environment by adding a transmission abstraction layer. It is characterized by versatility, high stability and less memory footprint. The experimental results show that the software is superior to the traditional software architecture in memory footprint, startup time and service interface response time. It can meet the harsh conditions of the embedded environment. [ABSTRACT FROM AUTHOR]

This paper constructed a password-based and leakage-resilient authenticated key exchange (AKE) protocol based on certificateless key encapsulation system. The scheme was secure against many attacks based on decisional Diffie-Hellman assumption in the standard model. The relative leakage rate of the encapsulated symmetric key was close to 1. [ABSTRACT FROM AUTHOR]

This paper proposed a mobile protocol for IPv6 -based urban vehicular networks. The protocol created the urban vehicular network architecture. In the protocol, when a vehicle joint an urban vehicular network, it acquired its home address. During the mobility process, a vehicle was always identified by its home address and did not need to be configured with a care-of address, so the care-of address configuration cost and delay were avoided. As a result, it reduced the mobility handover cost and delay. The protocol did not involve a vehicle in the mobility handover process, so it avoided the extra mobility handover cost and delay caused by the packet loss due to a vehicle's high speed. The simulation data show that the protocol has better performance. [ABSTRACT FROM AUTHOR]

In order to improve the working efficiency of ZigBee, this paper chose ZigBee throughput as the standard to assess the effect of clear channel assessment mode on the coexistence of ZigBee and Wi-Fi. Experiment results show that ZigBee performance can be optimized by choosing suitable clear channel assessment mode. [ABSTRACT FROM AUTHOR]