Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317815
M. Ulema
Summary form only given. Wireless sensor networks are examples of the paradigm shift taking place in wireless network architectures. A wireless sensor network consists of large numbers of sensors, which are tiny, low-cost, low-power radio devices dedicated to performing certain functions such as collecting various environmental data and sending them to infrastructure processing nodes. The field of wireless sensor networking is also gaining greater interest among not only researchers but also diverse groups such as environmental, public safety, medicine, and military. This tutorial starts with an overview of the wireless sensor networks. A review of the current technologies used for these types of wireless networks is provided next. The focus is on the architectural issues such as topology, routing, and protocols. Finally, the network management issues related to wireless sensor networks are discussed. The tutorial concludes with a discussion of the open research problems in this area.
{"title":"Wireless sensor networks: architectures, protocols, and management","authors":"M. Ulema","doi":"10.1109/NOMS.2004.1317815","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317815","url":null,"abstract":"Summary form only given. Wireless sensor networks are examples of the paradigm shift taking place in wireless network architectures. A wireless sensor network consists of large numbers of sensors, which are tiny, low-cost, low-power radio devices dedicated to performing certain functions such as collecting various environmental data and sending them to infrastructure processing nodes. The field of wireless sensor networking is also gaining greater interest among not only researchers but also diverse groups such as environmental, public safety, medicine, and military. This tutorial starts with an overview of the wireless sensor networks. A review of the current technologies used for these types of wireless networks is provided next. The focus is on the architectural issues such as topology, routing, and protocols. Finally, the network management issues related to wireless sensor networks are discussed. The tutorial concludes with a discussion of the open research problems in this area.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133176917","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317740
Z. B. Daho, N. Simoni, M. Chevanne, S. Betgé-Brezetz
This paper proposes enhancements for information modeling to support service and network management integration. Despite the existence of management standard models (TMN, TMF, DMTF), it seems that operators are facing difficulties choosing the appropriate model, defining its instances and achieving its implementations. The analysis of this situation stresses the need for an information model able to represent the real world objects independently of their management. To respond to this key requirement, we propose solutions, based on a metamodel, that guarantee information coherence, self-management capability and management integration. These propositions allow the operators to support new workflows and to handle new services efficiently. Furthermore, the M3100 model, the MTNM model and the ENST model are applied to model an ADSL network example.
{"title":"An information model for service and network management integration: from needs towards solutions","authors":"Z. B. Daho, N. Simoni, M. Chevanne, S. Betgé-Brezetz","doi":"10.1109/NOMS.2004.1317740","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317740","url":null,"abstract":"This paper proposes enhancements for information modeling to support service and network management integration. Despite the existence of management standard models (TMN, TMF, DMTF), it seems that operators are facing difficulties choosing the appropriate model, defining its instances and achieving its implementations. The analysis of this situation stresses the need for an information model able to represent the real world objects independently of their management. To respond to this key requirement, we propose solutions, based on a metamodel, that guarantee information coherence, self-management capability and management integration. These propositions allow the operators to support new workflows and to handle new services efficiently. Furthermore, the M3100 model, the MTNM model and the ENST model are applied to model an ADSL network example.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"948 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123309116","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317771
Hyoun-Mi Choi, Mi-Jung Choi, J. W. Hong
Today, we are witnessing more distributed systems on enterprise networks and on the Internet. In general, a distributed system is composed of many subsystems. It is difficult to effectively manage the configuration information of distributed systems because they may be deployed with different software components and run on heterogeneous computing platforms. In addition, the configuration information of a subsystem has complex relations with the information of other subsystems, so it is difficult to provide automatic reconfiguration of related subsystems. To overcome the difficulties, we propose a management information model that considers the relations among subsystems and the Simple Object Access Protocol (SOAP) as a communication method. This paper presents the design and implementation of X-CONF (XML-based configuration management system) for a distributed system. For validation, we have developed the X-CONF for NG-MON, which is a distributed and real-time Internet traffic monitoring and analysis system.
{"title":"Design and implementation of XML-based configuration management system for distributed systems","authors":"Hyoun-Mi Choi, Mi-Jung Choi, J. W. Hong","doi":"10.1109/NOMS.2004.1317771","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317771","url":null,"abstract":"Today, we are witnessing more distributed systems on enterprise networks and on the Internet. In general, a distributed system is composed of many subsystems. It is difficult to effectively manage the configuration information of distributed systems because they may be deployed with different software components and run on heterogeneous computing platforms. In addition, the configuration information of a subsystem has complex relations with the information of other subsystems, so it is difficult to provide automatic reconfiguration of related subsystems. To overcome the difficulties, we propose a management information model that considers the relations among subsystems and the Simple Object Access Protocol (SOAP) as a communication method. This paper presents the design and implementation of X-CONF (XML-based configuration management system) for a distributed system. For validation, we have developed the X-CONF for NG-MON, which is a distributed and real-time Internet traffic monitoring and analysis system.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124052912","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317789
Hosoon Ku, D. Wells, Jean-Luc Scherer
Public Ethernet is a new definition for a broadband access environment and it is the natural evolution and enabler of universal broadband services by combining cost-effective proven Ethernet technology and reliable public network characteristics. In this paper we present an Ethernet connection manager (ECM) that supports the deployment of customer services across the Ethernet access networks. ECM removes the need of manual configuration of low-level parameters into access networks for virtual local area network (VLAN) setup by provisioning the VLAN tags, link bandwidth, and IEEE 802.1p markings for quality of service (QoS) profiles. To verify the performance and scalability issues on deploying several hundreds or even thousands of network elements, a set of tests were performed using a simulated network to determine the average time to deploy a service. As expected the time to provision the services increases as the number of records within the database increases.
{"title":"Public Ethernet connection management systems for IP access networks","authors":"Hosoon Ku, D. Wells, Jean-Luc Scherer","doi":"10.1109/NOMS.2004.1317789","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317789","url":null,"abstract":"Public Ethernet is a new definition for a broadband access environment and it is the natural evolution and enabler of universal broadband services by combining cost-effective proven Ethernet technology and reliable public network characteristics. In this paper we present an Ethernet connection manager (ECM) that supports the deployment of customer services across the Ethernet access networks. ECM removes the need of manual configuration of low-level parameters into access networks for virtual local area network (VLAN) setup by provisioning the VLAN tags, link bandwidth, and IEEE 802.1p markings for quality of service (QoS) profiles. To verify the performance and scalability issues on deploying several hundreds or even thousands of network elements, a set of tests were performed using a simulated network to determine the average time to deploy a service. As expected the time to provision the services increases as the number of records within the database increases.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127881195","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317746
E. Al-Shaer, Yongning Tang
Although IP multicasting has been deployed for more than a decade, management of multicast networks and services is still a challenging problem. The fact that IP multicast is a receiver-oriented and stateless protocol makes end-to-end multicast monitoring an intractable task. Important multicast information such as join/leave status, group membership, tree information, path/traffic characteristics, and session status is either unrevealed or distributed in various locations on the network. In this paper, we present a new remote passive multicast monitoring infrastructure, called MRMON, to capture, analyze and present multicast session, traffic and membership information in real time. The MRMON probes inhabit a well-organized multicast information structure (MIB) that provides a comprehensive view of multicast network activities in remote subnets. We show how information can be collected from different MRMON probes and then correlated to diagnose multicast session problems. MRMON is a crucial step toward effective multicast management, and our goal is to promote MRMON as a standard MIB in multicast management.
{"title":"MRMON: remote multicast monitoring","authors":"E. Al-Shaer, Yongning Tang","doi":"10.1109/NOMS.2004.1317746","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317746","url":null,"abstract":"Although IP multicasting has been deployed for more than a decade, management of multicast networks and services is still a challenging problem. The fact that IP multicast is a receiver-oriented and stateless protocol makes end-to-end multicast monitoring an intractable task. Important multicast information such as join/leave status, group membership, tree information, path/traffic characteristics, and session status is either unrevealed or distributed in various locations on the network. In this paper, we present a new remote passive multicast monitoring infrastructure, called MRMON, to capture, analyze and present multicast session, traffic and membership information in real time. The MRMON probes inhabit a well-organized multicast information structure (MIB) that provides a comprehensive view of multicast network activities in remote subnets. We show how information can be collected from different MRMON probes and then correlated to diagnose multicast session problems. MRMON is a crucial step toward effective multicast management, and our goal is to promote MRMON as a standard MIB in multicast management.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132270413","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317637
Kaustubh S. Phanse, L. Dasilva
The management of mobile ad hoc networks (MANETs) is a challenging task. Previous work on this topic has focused largely on the monitoring and data collection aspects of network management; literature on the provisioning of devices and protocol support for MANET configuration is scarce. We present a solution suite to extend policy-based management, for the first time, to MANETs. The solution suite consists of four schemes - k-hop clustering, dynamic service redundancy (DynaSeR), policy negotiation, and automated service discovery - each addressing different challenges in managing ad hoc networks. We propose extensions to the standard common open policy service (COPS) protocol for use in MANETs, and evaluate the system performance using simulations.
移动特设网络（MANET）的管理是一项极具挑战性的任务。以前有关这一主题的工作主要集中在网络管理的监控和数据收集方面；有关城域网配置的设备供应和协议支持的文献很少。我们提出了一套解决方案，首次将基于策略的管理扩展到城域网。该解决方案套件包括四种方案--k-hop 集群、动态服务冗余（DynaSeR）、策略协商和自动服务发现--每种方案都能应对管理 ad hoc 网络中的不同挑战。我们对用于城域网的标准通用开放策略服务（COPS）协议提出了扩展建议，并通过模拟对系统性能进行了评估。
{"title":"Protocol support for policy-based management of mobile ad hoc networks","authors":"Kaustubh S. Phanse, L. Dasilva","doi":"10.1109/NOMS.2004.1317637","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317637","url":null,"abstract":"The management of mobile ad hoc networks (MANETs) is a challenging task. Previous work on this topic has focused largely on the monitoring and data collection aspects of network management; literature on the provisioning of devices and protocol support for MANET configuration is scarce. We present a solution suite to extend policy-based management, for the first time, to MANETs. The solution suite consists of four schemes - k-hop clustering, dynamic service redundancy (DynaSeR), policy negotiation, and automated service discovery - each addressing different challenges in managing ad hoc networks. We propose extensions to the standard common open policy service (COPS) protocol for use in MANETs, and evaluate the system performance using simulations.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130972423","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317671
R. Bahati, M. Bauer
The recent advancement in network technologies has made it possible for the convergence of voice and data networks. In particular, the differentiated services (DiffServ) model has helped in bridging the diverse performance requirements between voice and non real-time applications such as file transfer and e-mail. One key feature of the DiffServ model is its promise to bring scalable service discrimination to the Internet and intranets. With the heterogeneous nature of today's distributed systems, however, there is a demand for flexible management systems that can cope with not only changes in resource needs and the perceived quality of applications (which is often user-dependent and application-specific), but also changes in the configuration of the distributed environment. Policy-based management has been proposed as a means of providing dynamic change in the behavior of applications and systems at run-time rather than through reengineering. The paper proposes a policy-enabled DiffServ architecture to provide predictable and measurable quality of service (QoS) for voice over Internet Protocol (VoIP) applications, and illustrates its performance.
{"title":"Quality of service provisioning for VoIP applications with policy-enabled differentiated services","authors":"R. Bahati, M. Bauer","doi":"10.1109/NOMS.2004.1317671","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317671","url":null,"abstract":"The recent advancement in network technologies has made it possible for the convergence of voice and data networks. In particular, the differentiated services (DiffServ) model has helped in bridging the diverse performance requirements between voice and non real-time applications such as file transfer and e-mail. One key feature of the DiffServ model is its promise to bring scalable service discrimination to the Internet and intranets. With the heterogeneous nature of today's distributed systems, however, there is a demand for flexible management systems that can cope with not only changes in resource needs and the perceived quality of applications (which is often user-dependent and application-specific), but also changes in the configuration of the distributed environment. Policy-based management has been proposed as a means of providing dynamic change in the behavior of applications and systems at run-time rather than through reengineering. The paper proposes a policy-enabled DiffServ architecture to provide predictable and measurable quality of service (QoS) for voice over Internet Protocol (VoIP) applications, and illustrates its performance.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132743963","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317779
Shiva J. Shiva, P. Damodar, K. Vishal
This paper proposes a solution for large scale network management using SNMP over SIP. SIP is defined as a general-purpose protocol for creating, modifying, and terminating sessions that works independently of the underlying transport protocols and without dependency on the type of session that is being established. Our work focuses on developing a SIP user agent that resides on the device or on an SNMP proxy and provides an efficient management interface.
{"title":"SNMP over SIP for network management","authors":"Shiva J. Shiva, P. Damodar, K. Vishal","doi":"10.1109/NOMS.2004.1317779","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317779","url":null,"abstract":"This paper proposes a solution for large scale network management using SNMP over SIP. SIP is defined as a general-purpose protocol for creating, modifying, and terminating sessions that works independently of the underlying transport protocols and without dependency on the type of session that is being established. Our work focuses on developing a SIP user agent that resides on the device or on an SNMP proxy and provides an efficient management interface.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128211603","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317651
Ezzat Kirmani, C. Hood
The methodology of probing is useful in fault localization, in periodic auditing of functionality of network elements, and in measuring the overall quality of network performance. Probes resulting in binary responses have been proposed in the literature to diagnose the up or down status of network nodes. A sharp upper bound is obtained for the probability that the most probable explanation (MPE) of the network states computed on the basis of probe results does not coincide with the true network state. This upper bound supplements a lower bound available in the literature. In considering the diagnosis of a set of priority nodes, two indices are introduced to assess the reliability of the probe results in the leaky noisy-AND model. These indices are useful in deciding whether or not the result of a binary probe should be followed up, by individual testing of the priority nodes. Some problems for future research are outlined.
{"title":"Diagnosing network states through intelligent probing","authors":"Ezzat Kirmani, C. Hood","doi":"10.1109/NOMS.2004.1317651","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317651","url":null,"abstract":"The methodology of probing is useful in fault localization, in periodic auditing of functionality of network elements, and in measuring the overall quality of network performance. Probes resulting in binary responses have been proposed in the literature to diagnose the up or down status of network nodes. A sharp upper bound is obtained for the probability that the most probable explanation (MPE) of the network states computed on the basis of probe results does not coincide with the true network state. This upper bound supplements a lower bound available in the literature. In considering the diagnosis of a set of priority nodes, two indices are introduced to assess the reliability of the probe results in the leaky noisy-AND model. These indices are useful in deciding whether or not the result of a binary probe should be followed up, by individual testing of the priority nodes. Some problems for future research are outlined.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132213213","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}
Pub Date : 2004-04-23DOI: 10.1109/NOMS.2004.1317791
Namje Park, Kiyoung Moon, S. Sohn
XML is a global standard for the Internet and e-business, and its use is growing in proportion to the spreading speed of e-commerce. Thus, a policy for providing a safer security service for exchanging e-documents within e-commerce is necessary. XKMS (XML key management specification), one of XML's security specifications, defines the protocol for distributing and registering public keys for verifying digital signatures and enciphering e-documents of e-commerce applications with various and complicated functions. This paper presents an XKMS-based key management system architecture and a service model using Java crypto technologies and XML security mechanisms.
{"title":"XML key management system for Web-based business application","authors":"Namje Park, Kiyoung Moon, S. Sohn","doi":"10.1109/NOMS.2004.1317791","DOIUrl":"https://doi.org/10.1109/NOMS.2004.1317791","url":null,"abstract":"XML is a global standard for the Internet and e-business, and its use is growing in proportion to the spreading speed of e-commerce. Thus, a policy for providing a safer security service for exchanging e-documents within e-commerce is necessary. XKMS (XML key management specification), one of XML's security specifications, defines the protocol for distributing and registering public keys for verifying digital signatures and enciphering e-documents of e-commerce applications with various and complicated functions. This paper presents an XKMS-based key management system architecture and a service model using Java crypto technologies and XML security mechanisms.","PeriodicalId":260367,"journal":{"name":"2004 IEEE/IFIP Network Operations and Management Symposium (IEEE Cat. No.04CH37507)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134115972","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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