P2P systems are categorized into tree-based and mesh-based systems according to their topologies. Mesh-based systems are considered more suitable for large-scale lnternet applications, but require optimization on late...P2P systems are categorized into tree-based and mesh-based systems according to their topologies. Mesh-based systems are considered more suitable for large-scale lnternet applications, but require optimization on latency issue. This paper proposes a content subscribing mechanism （CSM） to eliminate unnecessary time delays during data relaying. A node can send content data to its neighbors as soon as it receives the data segment. No additional time is taken during the interactive stages prior to data segment transmission of streaming content. CSM consists of three steps. First, every node records its historical segments latency, and adopts gamma distribution, which possesses powerful expression ability, to express latency statistics. Second, a node predicts subscribing success ratio of every neighbor by comparing the gamma distribution parameters of the node and its neighbors before selecting a neighbor node to subscribe a data segment. The above steps would not increase latency as they are executed before the data segments are ready at the neighbor nodes. Finally, the node, which was subscribed to, sends the subscribed data segment to the subscriber immediately when it has the data segment. Experiments show that CSM significantly reduces the content data transmission latency.展开更多
Journal of Palaeogeography will totally publish 4 issues in 2006 with RMB￥25．00 per copy and RMB￥ 100.00 per volume．The overseas readers can subscribe the journal directly from the editorial office．We only charge...Journal of Palaeogeography will totally publish 4 issues in 2006 with RMB￥25．00 per copy and RMB￥ 100.00 per volume．The overseas readers can subscribe the journal directly from the editorial office．We only charge the corresponding international postage in addition and the average postage is RMB￥30．00 terminally and RMB￥120．00 yearly．展开更多
Finance and Trade Economics(monthly) is sponsored by the Institute of Finance and Trade Economics,and directed by the Chinese Academy of Social Sciences.It is one of the oldest and most prestigious journals in economi...Finance and Trade Economics(monthly) is sponsored by the Institute of Finance and Trade Economics,and directed by the Chinese Academy of Social Sciences.It is one of the oldest and most prestigious journals in economics in China,展开更多
The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications ...The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications services,the implementation of the number portability policy,and the intensifying competition among operators.At the same time,users'consumption preferences and choices are evolving.Excellent churn prediction models must be created in order to accurately predict the churn tendency,since keeping existing customers is far less expensive than acquiring new ones.But conventional or learning-based algorithms can only go so far into a single subscriber's data;they cannot take into consideration changes in a subscriber's subscription and ignore the coupling and correlation between various features.Additionally,the current churn prediction models have a high computational burden,a fuzzy weight distribution,and significant resource economic costs.The prediction algorithms involving network models currently in use primarily take into account the private information shared between users with text and pictures,ignoring the reference value supplied by other users with the same package.This work suggests a user churn prediction model based on Graph Attention Convolutional Neural Network(GAT-CNN)to address the aforementioned issues.The main contributions of this paper are as follows:Firstly,we present a three-tiered hierarchical cloud-edge cooperative framework that increases the volume of user feature input by means of two aggregations at the device,edge,and cloud layers.Second,we extend the use of users'own data by introducing self-attention and graph convolution models to track the relative changes of both users and packages simultaneously.Lastly,we build an integrated offline-online system for churn prediction based on the strengths of the two models,and we experimentally validate the efficacy of cloudside collaborative training and inference.In summary,the churn prediction model based on Graph Attention Convolutional Neural Network presented in this paper can effectively address the drawbacks of conventional algorithms and offer telecom operators crucial decision support in developing subscriber retention strategies and cutting operational expenses.展开更多
To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while r...To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while receiving data themselves.A dissemination tree is constructed among the subscribers based on MD5 where the publisher acts as the root. The proposed method provides bucket construction target selection and path updates furthermore the property of one-way dissemination is proven.That the average out-going degree of a node is 2 is guaranteed with the proposed LBDD.The experiments on data distribution delay data distribution rate and load distribution are conducted. Experimental results show that the LBDD method aids in shaping the task load between the publisher and subscribers and outperforms the point-to-point approach.展开更多
WITH the increasing spread of the electronic age into all spheres of our lives,it comes as no surprise that print media publications have generally taken a knock in sales over the past few years.People have turned fro...WITH the increasing spread of the electronic age into all spheres of our lives,it comes as no surprise that print media publications have generally taken a knock in sales over the past few years.People have turned from subscribing to newspapers and buying books to purchasing e-books and surfing the Internet,and now,learning online has become a more convenient and efficient option.These changes pose great challenges to the online sharers of information;while consumers are becoming more and more cautious when paying for knowledge.展开更多
Publish/subscribe paradigm paves a way to integrate and serve many scalable, inter-operable Internet of Things(IoT) applications. The increasing IoT applications require new properties of publish/subscribe communicati...Publish/subscribe paradigm paves a way to integrate and serve many scalable, inter-operable Internet of Things(IoT) applications. The increasing IoT applications require new properties of publish/subscribe communication model, for example, strict quality of service(Qo S) guarantees, supporting a large number of widely distributed devices, etc. Software Defined Networking(SDN) enables personalized programming and individualized QoS supports for different applications. The combination of the two will have a good prospect. In this paper, we present an IoT-oriented communication platform which combines the publish/subscribe paradigm with SDN, aiming at establishing an IoT ecosystem to facilitate IoT services/applications accessing internet. We design the interaction logic of topic-based publish/subscribe middleware, and describe the setup and maintenance of topology information as well as event routing in detail, considering the characteristics of SDN. Finally, we exemplify its practicability with a deployed District Heating Control and Information Service System(DHCISS) and validity the effectiveness with some experiments.展开更多
Cooperation allows wireless network users to benefit from various gains such as an in- crease in the achieved rate or an improvement in the bit error rate. In the paper, we propose a distributed Hierarchical Game （HG...Cooperation allows wireless network users to benefit from various gains such as an in- crease in the achieved rate or an improvement in the bit error rate. In the paper, we propose a distributed Hierarchical Game （HG） theoretic framework over multi-user cooperative communication networks to stimulate cooperation and improve the network performance. First, we study a two- user decision making game in the OFDMA based subscriber cooperative relaying network, in which subscribers transmit their own data in the first phase, while helping to retransmit their partner＇s or choosing to freeride in the second phase. Instead of consulting to a global optimal solution, we decouple the cooperation resource allocation into two level subproblems： a user level Nash game for distributed cooperation decision and a Base Station （BS） level coalition game for centralized resource allocation. In the proposed HG algorithm, where mutual cooperation is preferred and total payoff is transferable, we prove it converges to a unique optimal equilibrium and resolve the subcarrier as-signment and power allocation among the couples. Besides, we discuss the existence of the publishing and rewarding coefficients in order to encourage cooperation. Then, we extend the HG to multi-user cases by coupling among subscribers according to the location information. The simulation results show that the proposed scheme with the distributed HG game achieves a well tradeoff between fairness and efficiency by improving the transmission efficiency of adverse users and outperforms those employing centralized schemes.展开更多
Publish/subscribe paradigm is often adopted to create the communication infrastructure of the Internet of Things(IoT)for many clients to access enormous real-time sensor data.However,most current publish/subscribe mid...Publish/subscribe paradigm is often adopted to create the communication infrastructure of the Internet of Things(IoT)for many clients to access enormous real-time sensor data.However,most current publish/subscribe middlewares are based on traditional ossified IP networks,which are difficult to enable Quality of Service(QoS).How to design the next generation publish/subscribe middleware has become an urgent problem.The emerging Software Defined Networking(SDN)provides new opportunities to improve the QoS of publish/subscribe facilities for delivering events in IoT owing to its customized programmability and centralized control.We can encode event topics,priorities and security policies into flow entries of SDN-enabled switches to satisfy personalized QoS needs.In this paper,we propose a cross-layer QoS enabled SDN-like publish/subscribe communication infrastructure,aiming at building an IoT platform to seamlessly connect IoT services with SDN networks and improving the QoS of delivering events.We first present an SDN-like topic-oriented publish/subscribe middleware architecture with a cross-layer QoS control framework.Then we discuss prototype implementation,including topic management,topology maintenance,event routing and policy management.In the end,we use differentiated services and cross-layer access control as cross-layer QoS scenarios to verify the prototype.Experimental results show that our middleware is effective.展开更多
The margin maximization problem in digital subscriber line（DSL） systems is investigated.The particle swarm optimization（PSO） theory is applied to the nonconvex margin optimization problem with the target power and...The margin maximization problem in digital subscriber line（DSL） systems is investigated.The particle swarm optimization（PSO） theory is applied to the nonconvex margin optimization problem with the target power and rate constraints.PSO is a new evolution algorithm based on the social behavior of swarms, which can solve discontinuous, nonconvex and nonlinear problems efficiently.The proposed algorithm can converge to the global optimal solution, and numerical example demonstrates that the proposed algorithm can guarantee the fast convergence within a few iterations.展开更多
With the rapid development of wireless local area network （WLAN） technology, an important target of indoor positioning systems is to improve the positioning accuracy while reducing the online calibration effort to o...With the rapid development of wireless local area network （WLAN） technology, an important target of indoor positioning systems is to improve the positioning accuracy while reducing the online calibration effort to overcome signal time-varying. A novel fingerprint positioning algorithm, known as the adaptive radio map with updated method based on hidden Markov model （HMM）, is proposed. It is shown that by using a collection of user traces that can be cheaply obtained, the proposed algorithm can take advantage of these data to update the labeled calibration data to further improve the position estimation accuracy. This algorithm is a combination of machine learning, information gain theory and fingerprinting. By collecting data and testing the algorithm in a realistic indoor WLAN environment, the experiment results indicate that, compared with the widely used K nearest neighbor algorithm, the proposed algorithm can improve the positioning accuracy while greatly reduce the calibration effort.展开更多
According to the security requirement of the short message service （SMS） industry application, a secure short message communication protocol is proposed. This is an application level protocol constructed on the stan...According to the security requirement of the short message service （SMS） industry application, a secure short message communication protocol is proposed. This is an application level protocol constructed on the standard SMS communication protocol using public key authentication and key agreement without the need of wireless public key infrastructure （WPKI）. Secure short message transmission and dynamic key agreement between mobile terminals and the accessing gateway axe realized. The security of the proposed protocol is validated through the BAN logic. Compared with the standard SMS protocol, the effective payload rate of our protocol can reach 91.4%, and subscriber identity module （SIM） tool kit （STK） applications based on our protocol suit well for all kinds of mobile terminals in practical application.展开更多
Smart parking systems are a crucial component of the “smart city” concept, especially in the age of the Internet of Things (IoT). They aim to take the stress out of finding a vacant parking spot in city centers, due...Smart parking systems are a crucial component of the “smart city” concept, especially in the age of the Internet of Things (IoT). They aim to take the stress out of finding a vacant parking spot in city centers, due to the increasing number of cars, especially during peak hours. To realize the concept of smart parking, IoT-enabling technologies must be utilized, as the traditional way of developing smart parking solutions entails a lack of scalability, compatibility with IoT-constrained devices, security, and privacy awareness. In this paper, we propose a secure and privacy-preserving framework for smart parking systems. The framework relies on the publish/subscribe communication model for exchanging a huge volume of data with a large number of clients. On one hand, it provides functional services, including parking vacancy detection, real-time information for drivers about parking availability, driver guidance, and parking reservation. On the other hand, it provides security approaches on both the network and application layers. In addition, it supports mutual authentication mechanisms between entities to ensure device/ data authenticity, and provide security protection for users. That makes our proposed framework resilient to various types of security attacks, such as replay, phishing, and man-in-the-middle attacks. Finally, we analyze the performance of our framework, which is suitable for IoT devices, in terms of computation and network overhead.展开更多
The?convergence of the Internet, sensor networks, and Radio Frequency Identification (RFID) systems has ushered to the concept of Internet of Things (IoT) which is capable of connecting daily things, making them smart...The?convergence of the Internet, sensor networks, and Radio Frequency Identification (RFID) systems has ushered to the concept of Internet of Things (IoT) which is capable of connecting daily things, making them smart through sensing, reasoning, and cooperating with other things. Further, RFID technology enables tracking of an object and assigning it a unique ID. IoT has the potential for a wide range of applications relating to healthcare, environment, transportation, cities… Moreover, the middleware is a basic component in the IoT architecture. It handles heterogeneity issues among IoT devices and provides a common framework for communication. More recently, the interest has focusing on developing publish/subscribe middleware systems for the IoT to allow asynchronous communication between the IoT devices. The scope of our paper is to study routing protocols for publish/subscribe schemes that include content and context-based routing. We propose an Energy-Efficient Content-Based Routing (EECBR) protocol for the IoT that minimizes the energy consumption. The proposed algorithm makes use of a virtual topology that is constructed in a centralized manner and then routes the events from the publishers to the intended interested subscribers in a distributed manner. EECBR has been simulated using Omnet++. The simulation results show that EECBR has a significant performance in term of the energy variance compared to the other schemes.展开更多
基金the National Natural Science Foundation of China (Nos. 60533090 and 60525108)the National Basic research Program (973) of China (No. 2002CB312101)+2 种基金the China-US Million Book Digital Library Project (www.cadal.zju.edu.cn)the Science and Technology Project of Zhejiang Province (Nos. 2005C13032 and 2005C11001-05)the Research Project of Education Department of Zhejiang Province (No. 20061352), China
文摘P2P systems are categorized into tree-based and mesh-based systems according to their topologies. Mesh-based systems are considered more suitable for large-scale lnternet applications, but require optimization on latency issue. This paper proposes a content subscribing mechanism （CSM） to eliminate unnecessary time delays during data relaying. A node can send content data to its neighbors as soon as it receives the data segment. No additional time is taken during the interactive stages prior to data segment transmission of streaming content. CSM consists of three steps. First, every node records its historical segments latency, and adopts gamma distribution, which possesses powerful expression ability, to express latency statistics. Second, a node predicts subscribing success ratio of every neighbor by comparing the gamma distribution parameters of the node and its neighbors before selecting a neighbor node to subscribe a data segment. The above steps would not increase latency as they are executed before the data segments are ready at the neighbor nodes. Finally, the node, which was subscribed to, sends the subscribed data segment to the subscriber immediately when it has the data segment. Experiments show that CSM significantly reduces the content data transmission latency.
文摘Journal of Palaeogeography will totally publish 4 issues in 2006 with RMB￥25．00 per copy and RMB￥ 100.00 per volume．The overseas readers can subscribe the journal directly from the editorial office．We only charge the corresponding international postage in addition and the average postage is RMB￥30．00 terminally and RMB￥120．00 yearly．
文摘Finance and Trade Economics(monthly) is sponsored by the Institute of Finance and Trade Economics,and directed by the Chinese Academy of Social Sciences.It is one of the oldest and most prestigious journals in economics in China,
基金supported by National Key R&D Program of China(No.2022YFB3104500)Natural Science Foundation of Jiangsu Province(No.BK20222013)Scientific Research Foundation of Nanjing Institute of Technology(No.3534113223036)。
文摘The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications services,the implementation of the number portability policy,and the intensifying competition among operators.At the same time,users'consumption preferences and choices are evolving.Excellent churn prediction models must be created in order to accurately predict the churn tendency,since keeping existing customers is far less expensive than acquiring new ones.But conventional or learning-based algorithms can only go so far into a single subscriber's data;they cannot take into consideration changes in a subscriber's subscription and ignore the coupling and correlation between various features.Additionally,the current churn prediction models have a high computational burden,a fuzzy weight distribution,and significant resource economic costs.The prediction algorithms involving network models currently in use primarily take into account the private information shared between users with text and pictures,ignoring the reference value supplied by other users with the same package.This work suggests a user churn prediction model based on Graph Attention Convolutional Neural Network(GAT-CNN)to address the aforementioned issues.The main contributions of this paper are as follows:Firstly,we present a three-tiered hierarchical cloud-edge cooperative framework that increases the volume of user feature input by means of two aggregations at the device,edge,and cloud layers.Second,we extend the use of users'own data by introducing self-attention and graph convolution models to track the relative changes of both users and packages simultaneously.Lastly,we build an integrated offline-online system for churn prediction based on the strengths of the two models,and we experimentally validate the efficacy of cloudside collaborative training and inference.In summary,the churn prediction model based on Graph Attention Convolutional Neural Network presented in this paper can effectively address the drawbacks of conventional algorithms and offer telecom operators crucial decision support in developing subscriber retention strategies and cutting operational expenses.
基金The National Key Basic Research Program of China(973 Program)
文摘To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while receiving data themselves.A dissemination tree is constructed among the subscribers based on MD5 where the publisher acts as the root. The proposed method provides bucket construction target selection and path updates furthermore the property of one-way dissemination is proven.That the average out-going degree of a node is 2 is guaranteed with the proposed LBDD.The experiments on data distribution delay data distribution rate and load distribution are conducted. Experimental results show that the LBDD method aids in shaping the task load between the publisher and subscribers and outperforms the point-to-point approach.
文摘WITH the increasing spread of the electronic age into all spheres of our lives,it comes as no surprise that print media publications have generally taken a knock in sales over the past few years.People have turned from subscribing to newspapers and buying books to purchasing e-books and surfing the Internet,and now,learning online has become a more convenient and efficient option.These changes pose great challenges to the online sharers of information;while consumers are becoming more and more cautious when paying for knowledge.
基金supported by National Hightech R&D Program of China (863 Program) under Grant (No. 2013AA102301)Natural Science Foundation of China under Grant (No. U1536112)
文摘Publish/subscribe paradigm paves a way to integrate and serve many scalable, inter-operable Internet of Things(IoT) applications. The increasing IoT applications require new properties of publish/subscribe communication model, for example, strict quality of service(Qo S) guarantees, supporting a large number of widely distributed devices, etc. Software Defined Networking(SDN) enables personalized programming and individualized QoS supports for different applications. The combination of the two will have a good prospect. In this paper, we present an IoT-oriented communication platform which combines the publish/subscribe paradigm with SDN, aiming at establishing an IoT ecosystem to facilitate IoT services/applications accessing internet. We design the interaction logic of topic-based publish/subscribe middleware, and describe the setup and maintenance of topology information as well as event routing in detail, considering the characteristics of SDN. Finally, we exemplify its practicability with a deployed District Heating Control and Information Service System(DHCISS) and validity the effectiveness with some experiments.
基金Acknowledgements This work is supported by the National Natural Science Foundation of China under Grant No. 60971083, National High-Tech Research and Development Plan of China under Grant No. 2009AA01Z206 and National International Science and Technology Cooperation Project under Granted NO.2008DFA12090.
文摘Cooperation allows wireless network users to benefit from various gains such as an in- crease in the achieved rate or an improvement in the bit error rate. In the paper, we propose a distributed Hierarchical Game （HG） theoretic framework over multi-user cooperative communication networks to stimulate cooperation and improve the network performance. First, we study a two- user decision making game in the OFDMA based subscriber cooperative relaying network, in which subscribers transmit their own data in the first phase, while helping to retransmit their partner＇s or choosing to freeride in the second phase. Instead of consulting to a global optimal solution, we decouple the cooperation resource allocation into two level subproblems： a user level Nash game for distributed cooperation decision and a Base Station （BS） level coalition game for centralized resource allocation. In the proposed HG algorithm, where mutual cooperation is preferred and total payoff is transferable, we prove it converges to a unique optimal equilibrium and resolve the subcarrier as-signment and power allocation among the couples. Besides, we discuss the existence of the publishing and rewarding coefficients in order to encourage cooperation. Then, we extend the HG to multi-user cases by coupling among subscribers according to the location information. The simulation results show that the proposed scheme with the distributed HG game achieves a well tradeoff between fairness and efficiency by improving the transmission efficiency of adverse users and outperforms those employing centralized schemes.
基金the National Key Research and Development Program of China(No.2018YFB1003800).
文摘Publish/subscribe paradigm is often adopted to create the communication infrastructure of the Internet of Things(IoT)for many clients to access enormous real-time sensor data.However,most current publish/subscribe middlewares are based on traditional ossified IP networks,which are difficult to enable Quality of Service(QoS).How to design the next generation publish/subscribe middleware has become an urgent problem.The emerging Software Defined Networking(SDN)provides new opportunities to improve the QoS of publish/subscribe facilities for delivering events in IoT owing to its customized programmability and centralized control.We can encode event topics,priorities and security policies into flow entries of SDN-enabled switches to satisfy personalized QoS needs.In this paper,we propose a cross-layer QoS enabled SDN-like publish/subscribe communication infrastructure,aiming at building an IoT platform to seamlessly connect IoT services with SDN networks and improving the QoS of delivering events.We first present an SDN-like topic-oriented publish/subscribe middleware architecture with a cross-layer QoS control framework.Then we discuss prototype implementation,including topic management,topology maintenance,event routing and policy management.In the end,we use differentiated services and cross-layer access control as cross-layer QoS scenarios to verify the prototype.Experimental results show that our middleware is effective.
基金supported by the National Natural Science Foundation of China for Distinguished Young Scholars (60525303)the National Natural Science Foundation of China (60904048+2 种基金 60404022 60604012)the Natural Science Foundation of Hebei province (F2005000390)
文摘The margin maximization problem in digital subscriber line（DSL） systems is investigated.The particle swarm optimization（PSO） theory is applied to the nonconvex margin optimization problem with the target power and rate constraints.PSO is a new evolution algorithm based on the social behavior of swarms, which can solve discontinuous, nonconvex and nonlinear problems efficiently.The proposed algorithm can converge to the global optimal solution, and numerical example demonstrates that the proposed algorithm can guarantee the fast convergence within a few iterations.
基金supported by the National Natural Science Foundation of China(61571162)the Major National Science and Technology Project(2014ZX03004003-005)
文摘With the rapid development of wireless local area network （WLAN） technology, an important target of indoor positioning systems is to improve the positioning accuracy while reducing the online calibration effort to overcome signal time-varying. A novel fingerprint positioning algorithm, known as the adaptive radio map with updated method based on hidden Markov model （HMM）, is proposed. It is shown that by using a collection of user traces that can be cheaply obtained, the proposed algorithm can take advantage of these data to update the labeled calibration data to further improve the position estimation accuracy. This algorithm is a combination of machine learning, information gain theory and fingerprinting. By collecting data and testing the algorithm in a realistic indoor WLAN environment, the experiment results indicate that, compared with the widely used K nearest neighbor algorithm, the proposed algorithm can improve the positioning accuracy while greatly reduce the calibration effort.
基金This work was supported by the Mobile Police Project of China(No.J1GAB23W013)National High Technology Research and Development Program of China(863 Program,No.2007AA01Z479).
文摘According to the security requirement of the short message service （SMS） industry application, a secure short message communication protocol is proposed. This is an application level protocol constructed on the standard SMS communication protocol using public key authentication and key agreement without the need of wireless public key infrastructure （WPKI）. Secure short message transmission and dynamic key agreement between mobile terminals and the accessing gateway axe realized. The security of the proposed protocol is validated through the BAN logic. Compared with the standard SMS protocol, the effective payload rate of our protocol can reach 91.4%, and subscriber identity module （SIM） tool kit （STK） applications based on our protocol suit well for all kinds of mobile terminals in practical application.
文摘Smart parking systems are a crucial component of the “smart city” concept, especially in the age of the Internet of Things (IoT). They aim to take the stress out of finding a vacant parking spot in city centers, due to the increasing number of cars, especially during peak hours. To realize the concept of smart parking, IoT-enabling technologies must be utilized, as the traditional way of developing smart parking solutions entails a lack of scalability, compatibility with IoT-constrained devices, security, and privacy awareness. In this paper, we propose a secure and privacy-preserving framework for smart parking systems. The framework relies on the publish/subscribe communication model for exchanging a huge volume of data with a large number of clients. On one hand, it provides functional services, including parking vacancy detection, real-time information for drivers about parking availability, driver guidance, and parking reservation. On the other hand, it provides security approaches on both the network and application layers. In addition, it supports mutual authentication mechanisms between entities to ensure device/ data authenticity, and provide security protection for users. That makes our proposed framework resilient to various types of security attacks, such as replay, phishing, and man-in-the-middle attacks. Finally, we analyze the performance of our framework, which is suitable for IoT devices, in terms of computation and network overhead.
文摘The?convergence of the Internet, sensor networks, and Radio Frequency Identification (RFID) systems has ushered to the concept of Internet of Things (IoT) which is capable of connecting daily things, making them smart through sensing, reasoning, and cooperating with other things. Further, RFID technology enables tracking of an object and assigning it a unique ID. IoT has the potential for a wide range of applications relating to healthcare, environment, transportation, cities… Moreover, the middleware is a basic component in the IoT architecture. It handles heterogeneity issues among IoT devices and provides a common framework for communication. More recently, the interest has focusing on developing publish/subscribe middleware systems for the IoT to allow asynchronous communication between the IoT devices. The scope of our paper is to study routing protocols for publish/subscribe schemes that include content and context-based routing. We propose an Energy-Efficient Content-Based Routing (EECBR) protocol for the IoT that minimizes the energy consumption. The proposed algorithm makes use of a virtual topology that is constructed in a centralized manner and then routes the events from the publishers to the intended interested subscribers in a distributed manner. EECBR has been simulated using Omnet++. The simulation results show that EECBR has a significant performance in term of the energy variance compared to the other schemes.
