The new generation network or future Internet will be heterogeneous not only in terms of link layer technologies but also in network layer protocols and addressing (or locating) schemes. The ID/locator split concept will be applied to the protocol stack so that heterogeneity of the network layer protocols/locators would be hidden from the transport and application layers. The applications identify communication peer hosts by their hostnames or IDs which are mapped to locators as the packets are pushed down the protocol stack. Hosts obtain hostname-to-ID&locator mapping records from hostname registries. The records are updated as mobile hosts move and acquire different locators. In this paper, we discuss a scheme of hostname formation and present some considerations for registering, retrieving, and updating the mapping records so that mobility is supported well in heterogeneous networks of the future.
新一代网络或未来的互联网不仅在链路层技术方面，而且在网络层协议和寻址(或定位)方案方面都将是异构的。ID/定位器分离的概念将应用于协议栈，这样网络层协议/定位器的异构性将对传输层和应用层隐藏起来。应用程序通过它们的主机名或id来识别通信对等主机，这些主机名或id在数据包被推下协议堆栈时映射到定位器。主机从主机名注册表获取hostname-to- id &locator映射记录。这些记录随着移动主机的移动和获取不同的定位器而更新。在本文中，我们讨论了主机名形成方案，并提出了注册、检索和更新映射记录的一些注意事项，以便在未来的异构网络中很好地支持移动性。
{"title":"Considerations for name resolution in heterogeneous mobile networks of the future","authors":"Ved P. Kafle, M. Inoue","doi":"10.1145/2002396.2002398","DOIUrl":"https://doi.org/10.1145/2002396.2002398","url":null,"abstract":"The new generation network or future Internet will be heterogeneous not only in terms of link layer technologies but also in network layer protocols and addressing (or locating) schemes. The ID/locator split concept will be applied to the protocol stack so that heterogeneity of the network layer protocols/locators would be hidden from the transport and application layers. The applications identify communication peer hosts by their hostnames or IDs which are mapped to locators as the packets are pushed down the protocol stack. Hosts obtain hostname-to-ID&locator mapping records from hostname registries. The records are updated as mobile hosts move and acquire different locators. In this paper, we discuss a scheme of hostname formation and present some considerations for registering, retrieving, and updating the mapping records so that mobility is supported well in heterogeneous networks of the future.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126868273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the wireless sensor network, traditional key management scheme such as public key cryptography is not suitable due to the limitations in terms of computational power, energy supply, and network bandwidth. In order to balance the security and efficiency, we propose a secure and low cost key establishment scheme. Our scheme selects exchanging data randomly and most data is not fixed. Therefore, it would force an adversary to conduct traffic analysis and maintains lower communication cost.
{"title":"An improved key establishment scheme for wireless sensor network","authors":"Jaesung Yoo, Yunho Lee, Dongho Won","doi":"10.1145/2002396.2002415","DOIUrl":"https://doi.org/10.1145/2002396.2002415","url":null,"abstract":"In the wireless sensor network, traditional key management scheme such as public key cryptography is not suitable due to the limitations in terms of computational power, energy supply, and network bandwidth. In order to balance the security and efficiency, we propose a secure and low cost key establishment scheme. Our scheme selects exchanging data randomly and most data is not fixed. Therefore, it would force an adversary to conduct traffic analysis and maintains lower communication cost.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127184155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes a new definition on names, addresses, identifiers, and locators based on a different framework. Starting with observation of the patterns how those terms are used, a new definition for the terms and their relations are presented. First, name and address are defined based on assignment, where a name denotes an entity itself, and an address denotes a point to which the entity is attached. On the other hand, identifier is used for locating an entity within a given space. Next, the relationship among those four terms is presented. Finally, we show how communication is performed with respect to the new definition.
{"title":"YANAIL: yet another definition on names, addresses, identifiers, and locators","authors":"Woojik Chun, Tae-Ho Lee, T. Choi","doi":"10.1145/2002396.2002399","DOIUrl":"https://doi.org/10.1145/2002396.2002399","url":null,"abstract":"This paper proposes a new definition on names, addresses, identifiers, and locators based on a different framework. Starting with observation of the patterns how those terms are used, a new definition for the terms and their relations are presented. First, name and address are defined based on assignment, where a name denotes an entity itself, and an address denotes a point to which the entity is attached. On the other hand, identifier is used for locating an entity within a given space. Next, the relationship among those four terms is presented. Finally, we show how communication is performed with respect to the new definition.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133069258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yufeng Xin, I. Baldine, A. Mandal, Chris Heermann, J. Chase, Aydan R. Yumerefendi
Embedding virtual topologies in physical network infrastructure has been an area of active research for the future Internet and network testbeds. Virtual network embedding is also useful for linking virtual compute clusters allocated from cloud providers. Using advanced networking technologies to interconnect distributed cloud sites is a promising way to provision on-demand large-scale virtualized networked systems for production and experimental purposes. In this paper, we study the virtual topology embedding problem in a networked cloud environment, in which a number of cloud provider sites are connected by multi-domain wide-area networks that support virtual networking technology. A user submits a request for a virtual topology, and the system plans a low-cost embedding and orchestrates requests to multiple cloud providers and network transit providers to instantiate the virtual topology according to the plan. We describe an efficient heuristic algorithm design and a prototype implementation within a GENI control framework candidate called ORCA.
{"title":"Embedding virtual topologies in networked clouds","authors":"Yufeng Xin, I. Baldine, A. Mandal, Chris Heermann, J. Chase, Aydan R. Yumerefendi","doi":"10.1145/2002396.2002403","DOIUrl":"https://doi.org/10.1145/2002396.2002403","url":null,"abstract":"Embedding virtual topologies in physical network infrastructure has been an area of active research for the future Internet and network testbeds. Virtual network embedding is also useful for linking virtual compute clusters allocated from cloud providers. Using advanced networking technologies to interconnect distributed cloud sites is a promising way to provision on-demand large-scale virtualized networked systems for production and experimental purposes.\u0000 In this paper, we study the virtual topology embedding problem in a networked cloud environment, in which a number of cloud provider sites are connected by multi-domain wide-area networks that support virtual networking technology. A user submits a request for a virtual topology, and the system plans a low-cost embedding and orchestrates requests to multiple cloud providers and network transit providers to instantiate the virtual topology according to the plan. We describe an efficient heuristic algorithm design and a prototype implementation within a GENI control framework candidate called ORCA.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"577 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134381194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Nascimento, Christian Esteve Rothenberg, M. Salvador, Carlos N. A. Corrêa, S. C. D. Lucena, M. Magalhães
The networking equipment market is being transformed by the need for greater openness and flexibility, not only for research purposes but also for in-house innovation by the equipment owners. In contrast to networking gear following the model of computer mainframes, where closed software runs on proprietary hardware, the software-defined networking approach effectively decouples the data from the control plane via an open API (i.e., OpenFlow protocol) that allows the (remote) control of packet forwarding engines. Motivated by this scenario, we propose RouteFlow, a commodity routing architecture that combines the line-rate performance of commercial hardware with the flexibility of open-source routing stacks (remotely) running on general purpose computers. The outcome is a novel point in the design space of commodity routing solutions with far-reaching implications towards virtual routers and IP networks as a service. This paper documents the progress achieved in the design and prototype implementation of our work and outlines our research agenda that calls for a community-driven approach.
{"title":"Virtual routers as a service: the RouteFlow approach leveraging software-defined networks","authors":"M. Nascimento, Christian Esteve Rothenberg, M. Salvador, Carlos N. A. Corrêa, S. C. D. Lucena, M. Magalhães","doi":"10.1145/2002396.2002405","DOIUrl":"https://doi.org/10.1145/2002396.2002405","url":null,"abstract":"The networking equipment market is being transformed by the need for greater openness and flexibility, not only for research purposes but also for in-house innovation by the equipment owners. In contrast to networking gear following the model of computer mainframes, where closed software runs on proprietary hardware, the software-defined networking approach effectively decouples the data from the control plane via an open API (i.e., OpenFlow protocol) that allows the (remote) control of packet forwarding engines. Motivated by this scenario, we propose RouteFlow, a commodity routing architecture that combines the line-rate performance of commercial hardware with the flexibility of open-source routing stacks (remotely) running on general purpose computers. The outcome is a novel point in the design space of commodity routing solutions with far-reaching implications towards virtual routers and IP networks as a service. This paper documents the progress achieved in the design and prototype implementation of our work and outlines our research agenda that calls for a community-driven approach.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"314 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132670168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As the Internet evolves into an irreplaceable service-oriented infrastructure, a key issue to consider is that of creating and managing a rich variety of novel services while keeping aware of individual requirements for QoE (Quality of Experience) guarantee. In this paper, we present our on-going effort of designing a futuristic service framework for flexible media-oriented service composition in Future Internet. In our framework, media-oriented contents, generic service, and programmable infrastructure cooperate to flexibly compose media-oriented services with diverse requirements according to user's context and resource heterogeneity.
{"title":"A futuristic service framework for flexible media-oriented service composition in future internet","authors":"Ju-Won Park, Dong-Hoon Yi, JongWon Kim","doi":"10.1145/1853079.1853098","DOIUrl":"https://doi.org/10.1145/1853079.1853098","url":null,"abstract":"As the Internet evolves into an irreplaceable service-oriented infrastructure, a key issue to consider is that of creating and managing a rich variety of novel services while keeping aware of individual requirements for QoE (Quality of Experience) guarantee. In this paper, we present our on-going effort of designing a futuristic service framework for flexible media-oriented service composition in Future Internet. In our framework, media-oriented contents, generic service, and programmable infrastructure cooperate to flexibly compose media-oriented services with diverse requirements according to user's context and resource heterogeneity.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122653741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Various path-diverse overlay construction schemes have been adapted widely for future internet technology in order to overcome the bandwidth scarcity and achieve efficient resource usage. In this paper, we propose a quite intuitional approach that deploys multi-hour ability to the path-diverse overlay construction for video streaming. Multi-hour ability exploits a simple phenomenon that bandwidth utilization varies from hour to hour. We show that multi-hour ability yields an important principle in the overlay construction, and as a result, each peer expects to achieve better quality of streaming.
{"title":"Deployment of multi-hour ability to overlay construction network for future internet","authors":"S. Ahn, C. Yoo","doi":"10.1145/1853079.1853091","DOIUrl":"https://doi.org/10.1145/1853079.1853091","url":null,"abstract":"Various path-diverse overlay construction schemes have been adapted widely for future internet technology in order to overcome the bandwidth scarcity and achieve efficient resource usage. In this paper, we propose a quite intuitional approach that deploys multi-hour ability to the path-diverse overlay construction for video streaming. Multi-hour ability exploits a simple phenomenon that bandwidth utilization varies from hour to hour. We show that multi-hour ability yields an important principle in the overlay construction, and as a result, each peer expects to achieve better quality of streaming.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130724965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Internet Routing Registries(IRR) have been around for quite some time now[1] with the sole purpose of providing the place for service providers to store their administrative, routing policy information which can be used in case of BGP malicious/misconfiguration events. Are there any useful service providers policy data stored in IRR? What current limited research has able to answer is that "Quality" of IRR databases is not known". By "Quality" we mean validity of Internet Number Resources e.g. IPv4, IPv6, AS Number registration, routing policy registration, etc by different network service providers in IRR. We have tried to answer this question by looking into the public IRR datasets of approximately last 4 years [2006--2010]. We have found out that current IRR datasets has a lot to offer than its known/practiced i.e. IRR has approximately 50k full peering available. We are investigating how many peering are in harmony with what BGP is announcing and also which is currently published in well known topology datasets like UCLA IRL[25]. As we believe that if accurate peering can be extracted from IRR than they can provide number of new links which are missing in Internet Topology datasets. It can also reduce the usage of active measurements which in itself is burden on the network. We are also designing BGP Security framework based on IRR which will more accurately perform origin AS authentication as well as inferring the complete policy(what is stored in IRR) of AS.
Internet Routing registry (IRR)已经存在很长一段时间了[1]，其唯一目的是为服务提供商提供存储其管理路由策略信息的场所，这些信息可以在BGP恶意/错误配置事件中使用。IRR中是否存储了有用的服务提供商策略数据?目前有限的研究能够回答的问题是，IRR数据库的“质量”尚不可知。我们所说的“质量”是指IRR中不同网络服务提供商对互联网号码资源的有效性，例如IPv4、IPv6、AS号注册、路由策略注册等。我们试图通过查看近4年[2006- 2010]的公开IRR数据集来回答这个问题。我们发现当前的IRR数据集比已知/实践的有很多可提供的，即IRR有大约5万个完整的对等互联可用。我们正在调查有多少对等网络与BGP所宣布的一致，以及目前在众所周知的拓扑数据集中(如UCLA IRL[25])发布的对等网络。因为我们相信，如果能够从IRR中提取准确的对等，那么它们就可以提供Internet拓扑数据集中缺失的新链路数量。它还可以减少主动测量的使用，主动测量本身就是网络的负担。我们还设计了基于IRR的BGP安全框架，该框架可以更准确地执行源AS认证，并推断出AS的完整策略(存储在IRR中的内容)。
{"title":"Public internet routing registries (IRR) evolution","authors":"Akmal Khan, Hyunchul Kim, T. Kwon, Yanghee Choi","doi":"10.1145/1853079.1853095","DOIUrl":"https://doi.org/10.1145/1853079.1853095","url":null,"abstract":"Internet Routing Registries(IRR) have been around for quite some time now[1] with the sole purpose of providing the place for service providers to store their administrative, routing policy information which can be used in case of BGP malicious/misconfiguration events. Are there any useful service providers policy data stored in IRR? What current limited research has able to answer is that \"Quality\" of IRR databases is not known\". By \"Quality\" we mean validity of Internet Number Resources e.g. IPv4, IPv6, AS Number registration, routing policy registration, etc by different network service providers in IRR. We have tried to answer this question by looking into the public IRR datasets of approximately last 4 years [2006--2010]. We have found out that current IRR datasets has a lot to offer than its known/practiced i.e. IRR has approximately 50k full peering available. We are investigating how many peering are in harmony with what BGP is announcing and also which is currently published in well known topology datasets like UCLA IRL[25]. As we believe that if accurate peering can be extracted from IRR than they can provide number of new links which are missing in Internet Topology datasets. It can also reduce the usage of active measurements which in itself is burden on the network. We are also designing BGP Security framework based on IRR which will more accurately perform origin AS authentication as well as inferring the complete policy(what is stored in IRR) of AS.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123943296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Youngbin Im, Hakyung Jung, Ji Hoon Lee, Wonjun Yoon, T. Kwon, Yanghee Choi
As the access patterns of mobile users are diverse and their traffic demand is growing, multiple wireless access networks become dominant and their coexistence will be the norm in the future Internet infrastructure. To evaluate protocols and algorithms in these heterogeneous wireless networking environments, testbed-based experiments are of crucial importance since mathematical modeling and simulation cannot reflect the high complexity of systems and wireless link dynamics sufficiently. Leveraging femtocell technologies, we propose and build a testbed in which WiFi access points and WiMAX base stations are integrated. We also implement the vertical handover functionality through the SIP protocol, and carry out comprehensive measurements to analyze vertical handover delays. The testbed measurements of vertical handovers reveal that the DHCP mechanism, the authentication process in WiMAX, and the probing process in WiFi incur substantial delay.
{"title":"Vertical handovers in multiple heterogeneous wireless networks: a measurement study for the future internet","authors":"Youngbin Im, Hakyung Jung, Ji Hoon Lee, Wonjun Yoon, T. Kwon, Yanghee Choi","doi":"10.1145/1853079.1853083","DOIUrl":"https://doi.org/10.1145/1853079.1853083","url":null,"abstract":"As the access patterns of mobile users are diverse and their traffic demand is growing, multiple wireless access networks become dominant and their coexistence will be the norm in the future Internet infrastructure. To evaluate protocols and algorithms in these heterogeneous wireless networking environments, testbed-based experiments are of crucial importance since mathematical modeling and simulation cannot reflect the high complexity of systems and wireless link dynamics sufficiently. Leveraging femtocell technologies, we propose and build a testbed in which WiFi access points and WiMAX base stations are integrated. We also implement the vertical handover functionality through the SIP protocol, and carry out comprehensive measurements to analyze vertical handover delays. The testbed measurements of vertical handovers reveal that the DHCP mechanism, the authentication process in WiMAX, and the probing process in WiFi incur substantial delay.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"76 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114036704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The use of licensed spectrum for wireless communication is driven by the need to control interference between operators. This regulation leads to inefficient utilization of spectrum and causes shortage of free spectrum that hinders the entry of new operators and introduction of new wireless technologies. In this work, we present an evolutionary model for which license-free operation is the spectrum sharing mode so that networks can be built freely by anyone and new technologies can be deployed as soon as they become available. The paradigm assumes users to have open access to all public networks without prior contracts with operators. Hence, freely roaming users will drive competition among wireless network access providers, who in turn can meet demand quickly by offering access at low price, high quality, in hitherto uncovered areas, and by means of novel superior technology. We present a straw-man design and discuss the inherent technical challenges that must be addressed.
{"title":"A future wireless internet beyond generations","authors":"G. Karlsson, Emre A. Yavuz, George C. Polyzos","doi":"10.1145/1853079.1853082","DOIUrl":"https://doi.org/10.1145/1853079.1853082","url":null,"abstract":"The use of licensed spectrum for wireless communication is driven by the need to control interference between operators. This regulation leads to inefficient utilization of spectrum and causes shortage of free spectrum that hinders the entry of new operators and introduction of new wireless technologies. In this work, we present an evolutionary model for which license-free operation is the spectrum sharing mode so that networks can be built freely by anyone and new technologies can be deployed as soon as they become available. The paradigm assumes users to have open access to all public networks without prior contracts with operators. Hence, freely roaming users will drive competition among wireless network access providers, who in turn can meet demand quickly by offering access at low price, high quality, in hitherto uncovered areas, and by means of novel superior technology. We present a straw-man design and discuss the inherent technical challenges that must be addressed.","PeriodicalId":409750,"journal":{"name":"International Conference of Future Internet","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114493177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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