Connected vehicles for safety and traffic efficient applications require device-to-device connections supporting one-to-many and many-to-many communication, precise absolute and relative positioning and distributed co...Connected vehicles for safety and traffic efficient applications require device-to-device connections supporting one-to-many and many-to-many communication, precise absolute and relative positioning and distributed computing. Currently, the 5.9 GHz Dedicated Short Range Communications (DSRC) and 4G-Long-Term Evolution (LTE) are available for connected vehicle services. But both have limitations in reliability or latency over large scale field operational tests and deployment. This paper proposes the device-to-device (D2D) connectivity framework based on publish-subscribe architecture, with Message Queue Telemetry Transport (MQTT) protocol. With the publish-subscribe communication paradigm, road mobile users can exchange data and information in moderate latency and high reliability manner, having the potential to support many Vehicle to Everything (V2X) applications, including vehicle to vehicle (V2V), vehicle to roadside infrastructure (V2I), and vehicle to bicycle (V2B). The D2D data exchanges also facilitate computing for absolute and relative precise real-time kinematic (RTK) posi-tioning. Vehicular experiments were conducted to evaluate the performance of the proposed publish-subscribe MQTT protocols in term of latency and reliability. The latency of data exchanges is measured by One-trip-time (OTT) and the reliability is measured by the packet loss rate (PLR). Our results show that the latency of GNSS raw data exchanges between vehicles through 4G cellular networks at the rate of 10 Hz and the data rates of 10 kbps are less than 300 ms while the reliability is over 96%. Vehicular positioning experiments have also shown that vehicles can exchange raw GNSS data and complete mov-ing-base RTK positioning with the positioning availability of 98%.展开更多
Automation has arrived in the low voltage grid domain. In the next few years, the secondary substation—at the barriers of medium and low voltage grids—will thus be upgraded to enable novel functions. In this paper, ...Automation has arrived in the low voltage grid domain. In the next few years, the secondary substation—at the barriers of medium and low voltage grids—will thus be upgraded to enable novel functions. In this paper, we present various smart grid applications running on such intelligent secondary substations(iSSN) including their interaction with each other. We integrate energy consumption and production data, as well as forecasts, sensed from the smart buildings’ energy management systems(BEMSs) into the operation of the low voltage grid. A suitable framework for those modular applications includes features to initiate their installation, update, removal, the remote operator site, and not requiring staff on-site for such typical reappearing maintenance tasks.展开更多
The Internet of Things(IoT)has been growing over the past few years due to its flexibility and ease of use in real-time applications.The IoT's foremost task is ensuring that there is proper communication among dif...The Internet of Things(IoT)has been growing over the past few years due to its flexibility and ease of use in real-time applications.The IoT's foremost task is ensuring that there is proper communication among different types of applications and devices,and that the application layer protocols fulfill this necessity.However,as the number of applications grows,it is necessary to modify or enhance the application layer protocols according to specific IoT applications,allowing specific issues to be addressed,such as dynamic adaption to network conditions and interoperability.Recently,several IoT application layer protocols have been enhanced and modified according to application requirements.However,no existing survey articles focus on these protocols.In this article,we survey traditional and recent advances in IoT application layer protocols,as well as relevant real-time applications and their adapted application layer protocols for improving performance.As changing the nature of protocols for each application is unrealistic,machine learning offers means of making protocols intelligent and is able to adapt dynamically.In this context,we focus on providing open challenges to drive IoT application layer protocols in such a direction.展开更多
The recent evolution of the Internet towards "Information-centric" transfer modes has renewed the interest in exploiting proxies to enhance seamless mobility. In this work, we focus on the case of multiple l...The recent evolution of the Internet towards "Information-centric" transfer modes has renewed the interest in exploiting proxies to enhance seamless mobility. In this work, we focus on the case of multiple levels of proxies in ICN architectures, in which content requests from mobile subscribers and the corresponding items are proactively cached to these proxies at different levels. Specifically, we present a multiple-level proactive caching model that selects the appropriate subset of proxies at different levels and supports distributed online decision procedures in terms of the tradeoff between delay and cache cost. We show via extensive simulations the reduction of up to 31.63% in the total cost relative to Full Caching, in which caching in all 1-level neighbor proxies is performed, and up to 84.21% relative to No Caching, in which no caching is used. Moreover, the proposed model outperforms other approaches with a flat cache structure in terms of the total cost.展开更多
The internet’s architecture today has a problem in routing information depending on what the receiver is interested in without knowing the sender and receiver addresses. As a result, the Publish-Subscribe paradigm wa...The internet’s architecture today has a problem in routing information depending on what the receiver is interested in without knowing the sender and receiver addresses. As a result, the Publish-Subscribe paradigm was developed. In this network, we build and use in the design, implementation, and evaluation of Publish-Subscribe network via destination driven multicast routing algorithm for selecting the shortest path in the network. Basically, the networks have Router to perform routing mechanism, the publisher is the producer of information, and the subscriber is the consumer of information with their own deferent type of module for facilitating their function. Every connection in the network is bidirectional way of communication (an undirected graph) with random seed available in the network. Each Router has topology management module for creating a picture of the networks and computing the available path. It informs to the forwarder in order to send the information of network for intended receiver. Record table module used for recording of the network information comes from the subscriber or the publisher via link state advertisement then it informs to the topology manager. In this network, the receiver and sender don’t expect to be active at the same time, don’t know each other’s addresses, and don’t use any blocking mechanisms or client send requests and server replay responses. The Publish-Subscribe network is first developed and designed enough, after which it is implemented and evaluated using the destination driven multicast routing algorithm (DDMC) to pick the shortest path in the network and active match published information. The proposed work evaluated via total bit (produced 1,000,000 bit per second), and throughput was 83.33%.展开更多
文摘Connected vehicles for safety and traffic efficient applications require device-to-device connections supporting one-to-many and many-to-many communication, precise absolute and relative positioning and distributed computing. Currently, the 5.9 GHz Dedicated Short Range Communications (DSRC) and 4G-Long-Term Evolution (LTE) are available for connected vehicle services. But both have limitations in reliability or latency over large scale field operational tests and deployment. This paper proposes the device-to-device (D2D) connectivity framework based on publish-subscribe architecture, with Message Queue Telemetry Transport (MQTT) protocol. With the publish-subscribe communication paradigm, road mobile users can exchange data and information in moderate latency and high reliability manner, having the potential to support many Vehicle to Everything (V2X) applications, including vehicle to vehicle (V2V), vehicle to roadside infrastructure (V2I), and vehicle to bicycle (V2B). The D2D data exchanges also facilitate computing for absolute and relative precise real-time kinematic (RTK) posi-tioning. Vehicular experiments were conducted to evaluate the performance of the proposed publish-subscribe MQTT protocols in term of latency and reliability. The latency of data exchanges is measured by One-trip-time (OTT) and the reliability is measured by the packet loss rate (PLR). Our results show that the latency of GNSS raw data exchanges between vehicles through 4G cellular networks at the rate of 10 Hz and the data rates of 10 kbps are less than 300 ms while the reliability is over 96%. Vehicular positioning experiments have also shown that vehicles can exchange raw GNSS data and complete mov-ing-base RTK positioning with the positioning availability of 98%.
基金supported by the Austrian Ministry for Transport,Innovation and Technology(BMVIT)the Austrian Research Promotion Agency(FFG)under Grant No.849902the Austrian Climate and Energy Fund(KLIEN)under Grant No.846141
文摘Automation has arrived in the low voltage grid domain. In the next few years, the secondary substation—at the barriers of medium and low voltage grids—will thus be upgraded to enable novel functions. In this paper, we present various smart grid applications running on such intelligent secondary substations(iSSN) including their interaction with each other. We integrate energy consumption and production data, as well as forecasts, sensed from the smart buildings’ energy management systems(BEMSs) into the operation of the low voltage grid. A suitable framework for those modular applications includes features to initiate their installation, update, removal, the remote operator site, and not requiring staff on-site for such typical reappearing maintenance tasks.
基金The authors would like to thank DST(SERB),Government of India for grant No.EEQ/2018/000888The work was also supported by the Archimedes Foundation under the Dora plus Grant 11-15/OO/11476We also acknowledge financial support to UoH-IoE by MHRD(F11/9/2019-U3(A)).
文摘The Internet of Things(IoT)has been growing over the past few years due to its flexibility and ease of use in real-time applications.The IoT's foremost task is ensuring that there is proper communication among different types of applications and devices,and that the application layer protocols fulfill this necessity.However,as the number of applications grows,it is necessary to modify or enhance the application layer protocols according to specific IoT applications,allowing specific issues to be addressed,such as dynamic adaption to network conditions and interoperability.Recently,several IoT application layer protocols have been enhanced and modified according to application requirements.However,no existing survey articles focus on these protocols.In this article,we survey traditional and recent advances in IoT application layer protocols,as well as relevant real-time applications and their adapted application layer protocols for improving performance.As changing the nature of protocols for each application is unrealistic,machine learning offers means of making protocols intelligent and is able to adapt dynamically.In this context,we focus on providing open challenges to drive IoT application layer protocols in such a direction.
基金supported by National Natural Science Foundation of China (Grant Nos. 61302078 and 61372108)National High-tech R&D Program of China (863 Program) (Grant Nos. 2011AA01A102)+1 种基金National S&T Major Project (Grant Nos. 2011ZX 03005-004-02)Beijing Higher Education Young Elite Teacher Project (Grant Nos. YETP0476)
文摘The recent evolution of the Internet towards "Information-centric" transfer modes has renewed the interest in exploiting proxies to enhance seamless mobility. In this work, we focus on the case of multiple levels of proxies in ICN architectures, in which content requests from mobile subscribers and the corresponding items are proactively cached to these proxies at different levels. Specifically, we present a multiple-level proactive caching model that selects the appropriate subset of proxies at different levels and supports distributed online decision procedures in terms of the tradeoff between delay and cache cost. We show via extensive simulations the reduction of up to 31.63% in the total cost relative to Full Caching, in which caching in all 1-level neighbor proxies is performed, and up to 84.21% relative to No Caching, in which no caching is used. Moreover, the proposed model outperforms other approaches with a flat cache structure in terms of the total cost.
文摘The internet’s architecture today has a problem in routing information depending on what the receiver is interested in without knowing the sender and receiver addresses. As a result, the Publish-Subscribe paradigm was developed. In this network, we build and use in the design, implementation, and evaluation of Publish-Subscribe network via destination driven multicast routing algorithm for selecting the shortest path in the network. Basically, the networks have Router to perform routing mechanism, the publisher is the producer of information, and the subscriber is the consumer of information with their own deferent type of module for facilitating their function. Every connection in the network is bidirectional way of communication (an undirected graph) with random seed available in the network. Each Router has topology management module for creating a picture of the networks and computing the available path. It informs to the forwarder in order to send the information of network for intended receiver. Record table module used for recording of the network information comes from the subscriber or the publisher via link state advertisement then it informs to the topology manager. In this network, the receiver and sender don’t expect to be active at the same time, don’t know each other’s addresses, and don’t use any blocking mechanisms or client send requests and server replay responses. The Publish-Subscribe network is first developed and designed enough, after which it is implemented and evaluated using the destination driven multicast routing algorithm (DDMC) to pick the shortest path in the network and active match published information. The proposed work evaluated via total bit (produced 1,000,000 bit per second), and throughput was 83.33%.