This paper uses a correlation dimension based nonlinear analysis approach to analyse the dynamics of network traffics with three different application protocols-HTTP, FTP and SMTP. First, the phase space is reconstruc...This paper uses a correlation dimension based nonlinear analysis approach to analyse the dynamics of network traffics with three different application protocols-HTTP, FTP and SMTP. First, the phase space is reconstructed and the embedding parameters are obtained by the mutual information method. Secondly, the correlation dimensions of three different traffics are calculated and the results of analysis have demonstrated that the dynamics of the three different application protocol traffics is different from each other in nature, i.e. HTTP and FTP traffics are chaotic, furthermore, the former is more complex than the later; on the other hand, SMTP traffic is stochastic. It is shown that correlation dimension approach is an efficient method to understand and to characterize the nonlinear dynamics of HTTP, FTP and SMTP protocol network traffics. This analysis provided insight into and a more accurate understanding of nonlinear dynamics of internet traffics which have a complex mixture of chaotic and stochastic components.展开更多
The wireless application protocol (WAP) protocol is now the leading standard for information services on wireless terminals like digital mobile phones. By the use of WAP, wireless devices, like mobile phones, are po...The wireless application protocol (WAP) protocol is now the leading standard for information services on wireless terminals like digital mobile phones. By the use of WAP, wireless devices, like mobile phones, are possibly infected with virus and worms. Though up to now there is no such attack, as the usage of script languages increases, there is a chance of malicious code injection. This paper discusses the threats with current WAP protocol, and how changes in the protocol and the increase in its usage will enable entry of real viruses. Future threat scenarios are presented along with suggestions to avoid these problems.展开更多
The “Internet of Things” (IoT) refers to a set of intelligent “objects” that can communicate with each other directly or through a network. The IoT is the embodiment of the idea that everything can be connected an...The “Internet of Things” (IoT) refers to a set of intelligent “objects” that can communicate with each other directly or through a network. The IoT is the embodiment of the idea that everything can be connected anywhere and at any time. The concept can be applied to sectors such as e-health, e-government, automotive, geographic information systems, remote sensing, home networking, e-commerce and climate change mitigation. Unlike the Internet, the IoT has its own constraints, notably those linked to heterogeneity. This divergence is linked to different protocols, technologies and algorithms implemented in these connected objects for their interconnection. It should be noted that IoT devices can communicate with each other using different protocols and dedicated M2M (Machine to Machine) communication technologies. The aim of this work is to find solutions for optimising energy consumption during data exchanges between connected objects, with respect to certain constraints by using firstly this exchange for only Message Queuing Telemetry Transport (MQTT) and secondly the combination of the MQTT protocol and the Constrained Application Protocol (CoAP) protocol to check the quantity of the energy optimized. The MQTT protocol, for example, is one of the most widely used protocols for connected objects. Admittedly, this protocol consumes less energy, but in the situation of a very large number of users, the problem of saturation inevitably arises. In this article, we propose a solution of optimising energy consumption by combining the MQTT protocol with the CoAP protocol which can allow to use the standby mode contrary to the use of MQTT where the broker is always being turning. This solution has not yet been implemented but is being discussed. In this article, we’re going to use the joulemeter which is an application developed by Microsoft to measure and estimate the energy consumption of computers and applications. In our case, we take the example of the “Service Broker for network connections” of the Windows’s 10 Operating System, in my own computer to show the difference between the consumption of energy without the standby mode and with standby mode, because with the MQTT, the Broker’s MQTT is always on. Now, with the combination MQTT and CoAP, it is possible that we have standby mode and to compare these two cases in term of consumption of an energy. And to do it, we must use the joulemeter that we installed in our computer to simulate it. This is achieved by using the CoAP protocol combined with the MQTT protocol. The aim of our work is to reduce energy consumption in order to solve the problem of saturation of the MQTT by linking it to CoAP protocol by using Joulemeter mentioned above.展开更多
Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless...Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless links, some QoS mechanisms should be provided. We put forward a RTP/RSVP transmission scheme with DSR-specific payload and QoS parameters by modifying the present WAP protocol stack. The simulation result shows that this scheme will provide adequate network bandwidth to keep the real-time transport of DSR data over either wirelined or wireless channels.展开更多
The Internet of Things (IoT) is a large-scale network of devices capable of sensing, data processing, and communicating with each other through different communication protocols. In today's technology ecosystem, I...The Internet of Things (IoT) is a large-scale network of devices capable of sensing, data processing, and communicating with each other through different communication protocols. In today's technology ecosystem, IoT interacts with many application areas such as smart city, smart building, security, traffic, remote monitoring, health, energy, disaster, agriculture, industry. The IoT network in these scenarios comprises tiny devices, gateways, and cloud platforms. An IoT network is able to keep these fundamental components in transmission under many conditions with lightweight communication protocols taking into account the limited hardware features (memory, processor, energy, etc.) of tiny devices. These lightweight communication protocols affect the network traffic, reliability, bandwidth, and energy consumption of the IoT application. Therefore, determining the most proper communication protocol for application developers emerges as an important engineering problem. This paper presents a straightforward overview of the lightweight communication protocols, technological advancements in application layer for the IoT ecosystem. The survey then analyzes various recent lightweight communication protocols and reviews their strengths and limitations. In addition, the paper explains the experimental comparison of Constrained Applications Protocol (CoAP), Message Queuing Telemetry (MQTT), and WebSocket protocols, more convenient for tiny IoT devices. Finally, we discuss future research directions of communication protocols for IoT.展开更多
In this paper, in order to implement the share and exchange of the ship product data, a new kind of global function model is established. By researching on the development and trend of the application of ship STEP (st...In this paper, in order to implement the share and exchange of the ship product data, a new kind of global function model is established. By researching on the development and trend of the application of ship STEP (standard for the exchange of product model data) standards, the AIM (application interpreted model) of AP216 is developed and improved as an example, aiming at the characteristics and practical engineering of ship industry in our country. The data exchange interfaces are formed based on STEP in the CAD/CAM for the ship by all function modules and shared databases under the global function model. The share and exchange of all information and data are solved in the design, manufacture and all life-cycle of ship products among different computer application systems. The research work makes foundation for the ship industry informatization.展开更多
The traditional wired networks in an industrial firm often encounters large difficulties,such as the cable installation,regular maintenance and cable replacement and so on,all these results in high cost.So,in this pap...The traditional wired networks in an industrial firm often encounters large difficulties,such as the cable installation,regular maintenance and cable replacement and so on,all these results in high cost.So,in this paper,we propose an IP-based hierarchical wireless network architecture and apply some of the technologies of 6LoWPAN to it.We verify the proposed architecture via real implementation with a wireless backbone,sensor networks and a connection between those networks.And the IP-based hierarchical industrial network is indeed an advanced network for harsh industrial environments.展开更多
his paper studies the vehicle CAN bus control technology, and analyzes the control system of automobile based on CAN technology. This paper focus on the design of single-chip microcomputer STC89C52 be as the platform ...his paper studies the vehicle CAN bus control technology, and analyzes the control system of automobile based on CAN technology. This paper focus on the design of single-chip microcomputer STC89C52 be as the platform to achieve the design of CAN bus, introduce in detail the structure and working principle of SJA1000 and PCA82C250, and on basis of it, we design the CAN bus interface, and gives the hardware circuit design and software process of SJA1000 initialization, receiving, sending message. The system can give some subsequent reference for CAN bus application.展开更多
Fixture design and planning is one of the most important manufacturing activities, playing a pivotal role in deciding the lead time for product development. Fixture design, which affects the part-quality in terms of g...Fixture design and planning is one of the most important manufacturing activities, playing a pivotal role in deciding the lead time for product development. Fixture design, which affects the part-quality in terms of geometric accuracy and surface finish, can be enhanced by using the product manufacturing information(PMI) stored in the neutral standard for the exchange of product model data(STEP) file, thereby integrating design and manufacturing. The present paper proposes a unique fixture design approach, to extract the geometry information from STEP application protocol(AP) 242 files of computer aided design(CAD) models, for providing automatic suggestions of locator positions and clamping surfaces. Automatic feature extraction software "FiXplan", developed using the programming language C#, is used to extract the part feature, dimension and geometry information. The information from the STEP AP 242 file is deduced using geometric reasoning techniques, which in turn is utilized for fixture planning. The developed software is observed to be adept in identifying the primary, secondary, and tertiary locating faces and locator position configurations of prismatic components. Structural analysis of the prismatic part under different locator positions was performed using commercial finite element method software, ABAQUS, and the optimized locator position was identified on the basis of minimum deformation of the workpiece.The area-ratio(base locator enclosed area(%)/work piece base area(%)) for the ideal locator configuration was observed as 33%. Experiments were conducted on a prismatic workpiece using a specially designed fixture, for different locator configurations. The surface roughness and waviness of the machined surfaces were analysed using an Alicona non-contact optical profilometer. The best surface characteristics were obtained for the surface machined under the ideal locator positions having an area-ratio of 33%, thus validating the predicted numerical results. The efficiency, capability and applicability of the developed software is demonstrated for the finishing operation of a sensor cover – a typical prismatic component having applications in the naval industry, under different locator configurations.The best results were obtained under the proposed ideal locator configuration of area-ratio 33%.展开更多
Integration of CAD/CAPP/CAM requires a common product information model with CAD as the key process in forming the model.CAD can not only meet the demands of design, but also meet the demands of the subsystems, such a...Integration of CAD/CAPP/CAM requires a common product information model with CAD as the key process in forming the model.CAD can not only meet the demands of design, but also meet the demands of the subsystems, such as CAPP and CAM.The product modelling system based on STEP (PMSS) uses the 1-DEAS system andadopts STEP as its mechanism to exchange product information.PMSS closely integrates with 1-DEAS and takes advantage of the functions of 1-DEAS to meet the demands of CAD/CAPP/CAM integration. For integration with othersystems, PMSS uses management tool for STEP file to manage information required by subsystems.展开更多
This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detaile...This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detailed querying a virtual observatory s resources. The overview is focused on enhancements of user experience, work with simple application messaging protocol(SAMP) and other interoperability that improves work with global list of spectra, plot window and analysis menu.展开更多
In this paper,we present a WItness based Data priority mEchanism(WIDE)for vehicles in the vicinity of an accident to facilitate liability decisions.WIDE evaluates the integrity of data generated by these vehicles,call...In this paper,we present a WItness based Data priority mEchanism(WIDE)for vehicles in the vicinity of an accident to facilitate liability decisions.WIDE evaluates the integrity of data generated by these vehicles,called witnesses,in the event of an accident to assure the reliability of data to be used for making liability decisions and ensure that such data are received from credible witnesses.To achieve this,WIDE introduces a two-level integrity assessment to achieve end-to-end integrity by initially ascertaining the integrity of data-producing sensors,and validating that data generated have not been altered on transit by compromised road-side units(RSUs)by executing a practical byzantine fault tolerance(pBFT)protocol to reach consensus on data reliability.Furthermore,WIDE utilises a blockchain based reputation management system(BRMS)to ensure that only data from highly reputable witnesses are utilised as contributing evidence for facilitating liability decisions.Finally,we formally verify the proposed framework against data integrity requirements using the Automated Verification of Internet Security Protocols and Applications(AVISPA)with High-Level Protocol Specification Language(HLPSL).Qualitative arguments show that our proposed framework is secured against identified security attacks and assures the reliability of data utilised for making liability decisions,while quantitative evaluations demonstrate that our proposal is practical for fully autonomous vehicle forensics.展开更多
基金Project supported in part by the National High Technology Research and Development Program of China (Grant No. 2007AA01Z480)
文摘This paper uses a correlation dimension based nonlinear analysis approach to analyse the dynamics of network traffics with three different application protocols-HTTP, FTP and SMTP. First, the phase space is reconstructed and the embedding parameters are obtained by the mutual information method. Secondly, the correlation dimensions of three different traffics are calculated and the results of analysis have demonstrated that the dynamics of the three different application protocol traffics is different from each other in nature, i.e. HTTP and FTP traffics are chaotic, furthermore, the former is more complex than the later; on the other hand, SMTP traffic is stochastic. It is shown that correlation dimension approach is an efficient method to understand and to characterize the nonlinear dynamics of HTTP, FTP and SMTP protocol network traffics. This analysis provided insight into and a more accurate understanding of nonlinear dynamics of internet traffics which have a complex mixture of chaotic and stochastic components.
文摘The wireless application protocol (WAP) protocol is now the leading standard for information services on wireless terminals like digital mobile phones. By the use of WAP, wireless devices, like mobile phones, are possibly infected with virus and worms. Though up to now there is no such attack, as the usage of script languages increases, there is a chance of malicious code injection. This paper discusses the threats with current WAP protocol, and how changes in the protocol and the increase in its usage will enable entry of real viruses. Future threat scenarios are presented along with suggestions to avoid these problems.
文摘The “Internet of Things” (IoT) refers to a set of intelligent “objects” that can communicate with each other directly or through a network. The IoT is the embodiment of the idea that everything can be connected anywhere and at any time. The concept can be applied to sectors such as e-health, e-government, automotive, geographic information systems, remote sensing, home networking, e-commerce and climate change mitigation. Unlike the Internet, the IoT has its own constraints, notably those linked to heterogeneity. This divergence is linked to different protocols, technologies and algorithms implemented in these connected objects for their interconnection. It should be noted that IoT devices can communicate with each other using different protocols and dedicated M2M (Machine to Machine) communication technologies. The aim of this work is to find solutions for optimising energy consumption during data exchanges between connected objects, with respect to certain constraints by using firstly this exchange for only Message Queuing Telemetry Transport (MQTT) and secondly the combination of the MQTT protocol and the Constrained Application Protocol (CoAP) protocol to check the quantity of the energy optimized. The MQTT protocol, for example, is one of the most widely used protocols for connected objects. Admittedly, this protocol consumes less energy, but in the situation of a very large number of users, the problem of saturation inevitably arises. In this article, we propose a solution of optimising energy consumption by combining the MQTT protocol with the CoAP protocol which can allow to use the standby mode contrary to the use of MQTT where the broker is always being turning. This solution has not yet been implemented but is being discussed. In this article, we’re going to use the joulemeter which is an application developed by Microsoft to measure and estimate the energy consumption of computers and applications. In our case, we take the example of the “Service Broker for network connections” of the Windows’s 10 Operating System, in my own computer to show the difference between the consumption of energy without the standby mode and with standby mode, because with the MQTT, the Broker’s MQTT is always on. Now, with the combination MQTT and CoAP, it is possible that we have standby mode and to compare these two cases in term of consumption of an energy. And to do it, we must use the joulemeter that we installed in our computer to simulate it. This is achieved by using the CoAP protocol combined with the MQTT protocol. The aim of our work is to reduce energy consumption in order to solve the problem of saturation of the MQTT by linking it to CoAP protocol by using Joulemeter mentioned above.
文摘Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless links, some QoS mechanisms should be provided. We put forward a RTP/RSVP transmission scheme with DSR-specific payload and QoS parameters by modifying the present WAP protocol stack. The simulation result shows that this scheme will provide adequate network bandwidth to keep the real-time transport of DSR data over either wirelined or wireless channels.
文摘The Internet of Things (IoT) is a large-scale network of devices capable of sensing, data processing, and communicating with each other through different communication protocols. In today's technology ecosystem, IoT interacts with many application areas such as smart city, smart building, security, traffic, remote monitoring, health, energy, disaster, agriculture, industry. The IoT network in these scenarios comprises tiny devices, gateways, and cloud platforms. An IoT network is able to keep these fundamental components in transmission under many conditions with lightweight communication protocols taking into account the limited hardware features (memory, processor, energy, etc.) of tiny devices. These lightweight communication protocols affect the network traffic, reliability, bandwidth, and energy consumption of the IoT application. Therefore, determining the most proper communication protocol for application developers emerges as an important engineering problem. This paper presents a straightforward overview of the lightweight communication protocols, technological advancements in application layer for the IoT ecosystem. The survey then analyzes various recent lightweight communication protocols and reviews their strengths and limitations. In addition, the paper explains the experimental comparison of Constrained Applications Protocol (CoAP), Message Queuing Telemetry (MQTT), and WebSocket protocols, more convenient for tiny IoT devices. Finally, we discuss future research directions of communication protocols for IoT.
基金Supported by Commission of the Basic ResearchScience and Technology for National Defence ( No.B192001C001).
文摘In this paper, in order to implement the share and exchange of the ship product data, a new kind of global function model is established. By researching on the development and trend of the application of ship STEP (standard for the exchange of product model data) standards, the AIM (application interpreted model) of AP216 is developed and improved as an example, aiming at the characteristics and practical engineering of ship industry in our country. The data exchange interfaces are formed based on STEP in the CAD/CAM for the ship by all function modules and shared databases under the global function model. The share and exchange of all information and data are solved in the design, manufacture and all life-cycle of ship products among different computer application systems. The research work makes foundation for the ship industry informatization.
基金MKE(the Ministry of Knowledge Economy),Korea,under the Convergence-ITRC support program(NIPA-2011C6150-1101-0004)supervised by the NIPA(National IT Industry Promotion Agency)KCC(Korea Communications Commis-sion),Korea,under the R&D program supervised by the KCA(Korea Communications Agency)(KCA-2011-08913-05001)
文摘The traditional wired networks in an industrial firm often encounters large difficulties,such as the cable installation,regular maintenance and cable replacement and so on,all these results in high cost.So,in this paper,we propose an IP-based hierarchical wireless network architecture and apply some of the technologies of 6LoWPAN to it.We verify the proposed architecture via real implementation with a wireless backbone,sensor networks and a connection between those networks.And the IP-based hierarchical industrial network is indeed an advanced network for harsh industrial environments.
文摘his paper studies the vehicle CAN bus control technology, and analyzes the control system of automobile based on CAN technology. This paper focus on the design of single-chip microcomputer STC89C52 be as the platform to achieve the design of CAN bus, introduce in detail the structure and working principle of SJA1000 and PCA82C250, and on basis of it, we design the CAN bus interface, and gives the hardware circuit design and software process of SJA1000 initialization, receiving, sending message. The system can give some subsequent reference for CAN bus application.
基金Department of Science and Technology,Government of India for providing financial support under the scheme FIST(No.SR/FST/ETI-388/2015)。
文摘Fixture design and planning is one of the most important manufacturing activities, playing a pivotal role in deciding the lead time for product development. Fixture design, which affects the part-quality in terms of geometric accuracy and surface finish, can be enhanced by using the product manufacturing information(PMI) stored in the neutral standard for the exchange of product model data(STEP) file, thereby integrating design and manufacturing. The present paper proposes a unique fixture design approach, to extract the geometry information from STEP application protocol(AP) 242 files of computer aided design(CAD) models, for providing automatic suggestions of locator positions and clamping surfaces. Automatic feature extraction software "FiXplan", developed using the programming language C#, is used to extract the part feature, dimension and geometry information. The information from the STEP AP 242 file is deduced using geometric reasoning techniques, which in turn is utilized for fixture planning. The developed software is observed to be adept in identifying the primary, secondary, and tertiary locating faces and locator position configurations of prismatic components. Structural analysis of the prismatic part under different locator positions was performed using commercial finite element method software, ABAQUS, and the optimized locator position was identified on the basis of minimum deformation of the workpiece.The area-ratio(base locator enclosed area(%)/work piece base area(%)) for the ideal locator configuration was observed as 33%. Experiments were conducted on a prismatic workpiece using a specially designed fixture, for different locator configurations. The surface roughness and waviness of the machined surfaces were analysed using an Alicona non-contact optical profilometer. The best surface characteristics were obtained for the surface machined under the ideal locator positions having an area-ratio of 33%, thus validating the predicted numerical results. The efficiency, capability and applicability of the developed software is demonstrated for the finishing operation of a sensor cover – a typical prismatic component having applications in the naval industry, under different locator configurations.The best results were obtained under the proposed ideal locator configuration of area-ratio 33%.
文摘Integration of CAD/CAPP/CAM requires a common product information model with CAD as the key process in forming the model.CAD can not only meet the demands of design, but also meet the demands of the subsystems, such as CAPP and CAM.The product modelling system based on STEP (PMSS) uses the 1-DEAS system andadopts STEP as its mechanism to exchange product information.PMSS closely integrates with 1-DEAS and takes advantage of the functions of 1-DEAS to meet the demands of CAD/CAPP/CAM integration. For integration with othersystems, PMSS uses management tool for STEP file to manage information required by subsystems.
基金supported by Agency of the Czech Republic-GACR(No.P103/13/08195S)the Development of Human Resources in Research and Development of Latest Soft Computing Methods and Their Application in Practical Project,Operational Programm Education for Competitiveness(No.CZ.1.07/2.3.00/20.0072)+1 种基金ESF State Budget of the Czech Republic,SGS(No.SP2013/114)VBTechnical University of Ostrava,Czech Republic
文摘This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detailed querying a virtual observatory s resources. The overview is focused on enhancements of user experience, work with simple application messaging protocol(SAMP) and other interoperability that improves work with global list of spectra, plot window and analysis menu.
文摘In this paper,we present a WItness based Data priority mEchanism(WIDE)for vehicles in the vicinity of an accident to facilitate liability decisions.WIDE evaluates the integrity of data generated by these vehicles,called witnesses,in the event of an accident to assure the reliability of data to be used for making liability decisions and ensure that such data are received from credible witnesses.To achieve this,WIDE introduces a two-level integrity assessment to achieve end-to-end integrity by initially ascertaining the integrity of data-producing sensors,and validating that data generated have not been altered on transit by compromised road-side units(RSUs)by executing a practical byzantine fault tolerance(pBFT)protocol to reach consensus on data reliability.Furthermore,WIDE utilises a blockchain based reputation management system(BRMS)to ensure that only data from highly reputable witnesses are utilised as contributing evidence for facilitating liability decisions.Finally,we formally verify the proposed framework against data integrity requirements using the Automated Verification of Internet Security Protocols and Applications(AVISPA)with High-Level Protocol Specification Language(HLPSL).Qualitative arguments show that our proposed framework is secured against identified security attacks and assures the reliability of data utilised for making liability decisions,while quantitative evaluations demonstrate that our proposal is practical for fully autonomous vehicle forensics.