A mobile edge cloud provides a platform to accommodate the offloaded traffic workload generated by mobile devices.It can significantly reduce the access delay for mobile application users.However,the high user mobilit...A mobile edge cloud provides a platform to accommodate the offloaded traffic workload generated by mobile devices.It can significantly reduce the access delay for mobile application users.However,the high user mobility brings significant challenges to the service provisioning for mobile users,especially to delay-sensitive mobile applications.With the objective to maximize a profit,which positively associates with the overall admitted traffic served by the local edge cloud,and negatively associates with the access delay as well as virtual machine migration delay,we study a fundamental problem in this paper:how to update the service provisioning solution for a given group of mobile users.Such a profit-maximization problem is formulated as a nonlinear integer linear programming and linearized by absolute value manipulation techniques.Then,we propose a framework of heuristic algorithms to solve this Nondeterministic Polynomial(NP)-hard problem.The numerical simulation results demonstrate the efficiency of the devised algorithms.Some useful summaries are concluded via the analysis of evaluation results.展开更多
Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supp...Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supply numerous ES.However,the ES delivered by both land use types have not yet been assessed simultaneously.Here we surveyed both church forests and their agricultural matrices,aiming to quantify,compare and unravel the drivers underlying tree-based ES supply,density and multifunctionality.We found that almost all church forests and half of the agricultural matrices provided high ES densities.ES multifunctionality was higher in the agricultural matrices,suggesting that people deliberately conserve or plant multifunctional tree species.Furthermore,the supply of all categories of ES was positively correlated with church forest age(p-value<0.001)in the agricultural matrix,while the extent of church forest was positively correlated with the density of all categories ecosystem services score in the church forests(p-value<0.001).Our results can be used to prioritize conservation efforts at sites that provide high levels of ES supply,ES density and ES multifunctionality,and to prioritize restoration efforts at sites with low levels thereof.展开更多
Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing informatio...Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing information technology capabilities and requirements. Many technologies are being merged with cloud computing, same as that orchestrations can boost cloud service provisioning process. The usage of orchestrations can play vital role to provision cloud services. Cloud service providers can create scalable cloud services at low cost by organizing cloud infrastructure by using cloud orchestrations. Dynamic orchestration flows can generate required cloud computing services to meet service level agreements and quality of services. There is a need to understand issues and barriers involved to integrate cloud orchestrations with cloud service provisioning process. There is also need to understand business related problems bordering cloud computing technology. There is much capacity to do targeted research work for cloud orchestrations and its integration with service level agreements as well as with SLI (service level integration) layer. In this article we have elaborated detailed analysis and identified a number of issues that will affect the cloud service users as well as cloud service providers and cloud service provisioning system. We are defining an approach to orchestrate cloud infrastructure by using orchestration flows, to generate cloud services in order to meet service level agreements and quality of standard.展开更多
In this paper, we present an approach to establish efficient and scalable service provisioning in the cloud environment using P2P-based infrastructure for storing, sharing and discovering services. Unlike most other P...In this paper, we present an approach to establish efficient and scalable service provisioning in the cloud environment using P2P-based infrastructure for storing, sharing and discovering services. Unlike most other P2P-based approaches, it allows flexible search queries, since all of them are executed against internal database presenting at each overlay node. Various issues concerning using this approach in the cloud environment, such as load-balancing, queuing, dealing with skewed data and dynamic attributes, are addressed in the paper. The infrastructure proposed in the paper can serve as a base for creating robust, scalable and reliable cloud systems, able to fulfill client’s QoS requirements, and at the same time introduce more efficient utilization of resources to the cloud provider.展开更多
Cooperation among service providers, network providers, and access providers in the Internet allows the creation of new services to offer to customers that are in other domains, thus increasing revenue. However, the I...Cooperation among service providers, network providers, and access providers in the Internet allows the creation of new services to offer to customers that are in other domains, thus increasing revenue. However, the Internet heterogeneous environment, where each provider has its own policies, infrastructure and business goals, hinders the deployment of more advanced communication services. This paper presents a Quality of Service （QoS） for Inter-Domain Services （QIDS） model that allows inter-domain QoS-aware services to be defined, configured, and adapted in a dynamic and on-demand fashion, among service providers. This is accomplished by： 1） the use of a common communication channel （business layer） where service providers publish and search for services, and interact with each other to contract and manage these services; 2） the templates to specify the business and technical characteristics of the services; 3） the automatic composition of services using service dements （smaller services） a^cording to performance and service-specific QoS parameters; and 4） the creation and enforcement of configuration rules for the underlying infrastructure. A prototype was implemented to validate QIDS and performance tests were conducted on an inter-domain Border Gateway Protocol （BGP）/Multiprotocol Label Switching （MPLS） Virtual Private Network （VPN） scenario.展开更多
容器作为物理资源的逻辑抽象,具有资源占用少、资源供给快等特点,适合工作负载突变的互联网应用模式,特别是面向微服务架构的新型服务范型.已有工作受限于物理机和虚拟化环境,或资源难以弹性供给或资源供给时效性较差,难以应对负载突变(...容器作为物理资源的逻辑抽象,具有资源占用少、资源供给快等特点,适合工作负载突变的互联网应用模式,特别是面向微服务架构的新型服务范型.已有工作受限于物理机和虚拟化环境,或资源难以弹性供给或资源供给时效性较差,难以应对负载突变(flash-crowds)场景.针对此问题提出了一种服务质量(quality of service,QoS)敏感的、基于前馈的容器资源弹性供给方法,该方法采用排队论刻画工作负载、资源利用率和响应时间的关联关系,构建应用性能模型.其中,响应时间采用模糊自适应卡尔曼滤波进行预测(前馈控制器),预测结果违背QoS是触发资源弹性供给的依据.基于CloudStone基准的实验结果显示,前馈控制器具有快速收敛的特点,对响应时间的预测误差小于10%.在flash-crowds场景下,相对于已有方法可有效保障应用的QoS.展开更多
It is foreseen that the Internet of Things (IoT) will comprise billions of connected devices, and this will make the provi?sioning and operation of some IoT connectivity services more challenging. Indeed, IoT services...It is foreseen that the Internet of Things (IoT) will comprise billions of connected devices, and this will make the provi?sioning and operation of some IoT connectivity services more challenging. Indeed, IoT services are very different from lega?cy Internet services because of their dimensioning figures and also because IoT services differ dramatically in terms of na?ture and constraints. For example, IoT services often rely on energy and CPU?constrained sensor technologies, regardless of whether the service is for home automation, smart building, e?health, or power or water metering on a regional or national scale. Also, some IoT services, such as dynamic monitoring of biometric data, manipulation of sensitive information, and pri?vacy needs to be safeguarded whenever this information is for?warded over the underlying IoT network infrastructure. This paper discusses how software?defined networking (SDN) can facilitate the deployment and operation of some advanced IoT services regardless of their nature or scope. SDN introduces a high degree of automation in service delivery and operation-from dynamic IoT service parameter exposure and negotiation to resource allocation, service fulfillment, and assurance. This paper does not argue that all IoT services must adopt SDN. Rather, it is left to the discretion of operators to decide which IoT services can best leverage SDN capabilities. This paper only discusses managed IoT services, i.e., services that are op?erated by a service provider.展开更多
One of the limitations of current content delivery networks is lack of support for environment aware content delivery. This paper first discusses the requirements of such support, and proposes a new metadata gateway b...One of the limitations of current content delivery networks is lack of support for environment aware content delivery. This paper first discusses the requirements of such support, and proposes a new metadata gateway based environment aware content delivery architecture. The paper discusses in some details key functions and technologies of environment aware content delivery architecture, including its APIs and control policies. Finally the paper presents an application to illustrate advantages of environment aware content delivery architecture in the context of next generation network.展开更多
基金partially supported by JSPS KAKENHI under Grant Number JP16J07062
文摘A mobile edge cloud provides a platform to accommodate the offloaded traffic workload generated by mobile devices.It can significantly reduce the access delay for mobile application users.However,the high user mobility brings significant challenges to the service provisioning for mobile users,especially to delay-sensitive mobile applications.With the objective to maximize a profit,which positively associates with the overall admitted traffic served by the local edge cloud,and negatively associates with the access delay as well as virtual machine migration delay,we study a fundamental problem in this paper:how to update the service provisioning solution for a given group of mobile users.Such a profit-maximization problem is formulated as a nonlinear integer linear programming and linearized by absolute value manipulation techniques.Then,we propose a framework of heuristic algorithms to solve this Nondeterministic Polynomial(NP)-hard problem.The numerical simulation results demonstrate the efficiency of the devised algorithms.Some useful summaries are concluded via the analysis of evaluation results.
基金flnancial support from VLIR-UOS,Belgium through the VLIR-IUC Interuniversity cooperation with Bahir Dar University,Ethiopia (BDU-IUC)
文摘Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supply numerous ES.However,the ES delivered by both land use types have not yet been assessed simultaneously.Here we surveyed both church forests and their agricultural matrices,aiming to quantify,compare and unravel the drivers underlying tree-based ES supply,density and multifunctionality.We found that almost all church forests and half of the agricultural matrices provided high ES densities.ES multifunctionality was higher in the agricultural matrices,suggesting that people deliberately conserve or plant multifunctional tree species.Furthermore,the supply of all categories of ES was positively correlated with church forest age(p-value<0.001)in the agricultural matrix,while the extent of church forest was positively correlated with the density of all categories ecosystem services score in the church forests(p-value<0.001).Our results can be used to prioritize conservation efforts at sites that provide high levels of ES supply,ES density and ES multifunctionality,and to prioritize restoration efforts at sites with low levels thereof.
文摘Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing information technology capabilities and requirements. Many technologies are being merged with cloud computing, same as that orchestrations can boost cloud service provisioning process. The usage of orchestrations can play vital role to provision cloud services. Cloud service providers can create scalable cloud services at low cost by organizing cloud infrastructure by using cloud orchestrations. Dynamic orchestration flows can generate required cloud computing services to meet service level agreements and quality of services. There is a need to understand issues and barriers involved to integrate cloud orchestrations with cloud service provisioning process. There is also need to understand business related problems bordering cloud computing technology. There is much capacity to do targeted research work for cloud orchestrations and its integration with service level agreements as well as with SLI (service level integration) layer. In this article we have elaborated detailed analysis and identified a number of issues that will affect the cloud service users as well as cloud service providers and cloud service provisioning system. We are defining an approach to orchestrate cloud infrastructure by using orchestration flows, to generate cloud services in order to meet service level agreements and quality of standard.
文摘In this paper, we present an approach to establish efficient and scalable service provisioning in the cloud environment using P2P-based infrastructure for storing, sharing and discovering services. Unlike most other P2P-based approaches, it allows flexible search queries, since all of them are executed against internal database presenting at each overlay node. Various issues concerning using this approach in the cloud environment, such as load-balancing, queuing, dealing with skewed data and dynamic attributes, are addressed in the paper. The infrastructure proposed in the paper can serve as a base for creating robust, scalable and reliable cloud systems, able to fulfill client’s QoS requirements, and at the same time introduce more efficient utilization of resources to the cloud provider.
文摘Cooperation among service providers, network providers, and access providers in the Internet allows the creation of new services to offer to customers that are in other domains, thus increasing revenue. However, the Internet heterogeneous environment, where each provider has its own policies, infrastructure and business goals, hinders the deployment of more advanced communication services. This paper presents a Quality of Service （QoS） for Inter-Domain Services （QIDS） model that allows inter-domain QoS-aware services to be defined, configured, and adapted in a dynamic and on-demand fashion, among service providers. This is accomplished by： 1） the use of a common communication channel （business layer） where service providers publish and search for services, and interact with each other to contract and manage these services; 2） the templates to specify the business and technical characteristics of the services; 3） the automatic composition of services using service dements （smaller services） a^cording to performance and service-specific QoS parameters; and 4） the creation and enforcement of configuration rules for the underlying infrastructure. A prototype was implemented to validate QIDS and performance tests were conducted on an inter-domain Border Gateway Protocol （BGP）/Multiprotocol Label Switching （MPLS） Virtual Private Network （VPN） scenario.
文摘容器作为物理资源的逻辑抽象,具有资源占用少、资源供给快等特点,适合工作负载突变的互联网应用模式,特别是面向微服务架构的新型服务范型.已有工作受限于物理机和虚拟化环境,或资源难以弹性供给或资源供给时效性较差,难以应对负载突变(flash-crowds)场景.针对此问题提出了一种服务质量(quality of service,QoS)敏感的、基于前馈的容器资源弹性供给方法,该方法采用排队论刻画工作负载、资源利用率和响应时间的关联关系,构建应用性能模型.其中,响应时间采用模糊自适应卡尔曼滤波进行预测(前馈控制器),预测结果违背QoS是触发资源弹性供给的依据.基于CloudStone基准的实验结果显示,前馈控制器具有快速收敛的特点,对响应时间的预测误差小于10%.在flash-crowds场景下,相对于已有方法可有效保障应用的QoS.
文摘It is foreseen that the Internet of Things (IoT) will comprise billions of connected devices, and this will make the provi?sioning and operation of some IoT connectivity services more challenging. Indeed, IoT services are very different from lega?cy Internet services because of their dimensioning figures and also because IoT services differ dramatically in terms of na?ture and constraints. For example, IoT services often rely on energy and CPU?constrained sensor technologies, regardless of whether the service is for home automation, smart building, e?health, or power or water metering on a regional or national scale. Also, some IoT services, such as dynamic monitoring of biometric data, manipulation of sensitive information, and pri?vacy needs to be safeguarded whenever this information is for?warded over the underlying IoT network infrastructure. This paper discusses how software?defined networking (SDN) can facilitate the deployment and operation of some advanced IoT services regardless of their nature or scope. SDN introduces a high degree of automation in service delivery and operation-from dynamic IoT service parameter exposure and negotiation to resource allocation, service fulfillment, and assurance. This paper does not argue that all IoT services must adopt SDN. Rather, it is left to the discretion of operators to decide which IoT services can best leverage SDN capabilities. This paper only discusses managed IoT services, i.e., services that are op?erated by a service provider.
文摘One of the limitations of current content delivery networks is lack of support for environment aware content delivery. This paper first discusses the requirements of such support, and proposes a new metadata gateway based environment aware content delivery architecture. The paper discusses in some details key functions and technologies of environment aware content delivery architecture, including its APIs and control policies. Finally the paper presents an application to illustrate advantages of environment aware content delivery architecture in the context of next generation network.
