The main concerns of network performance are throughput, end-to-end packet delay and packet loss. A high-performance network is characterized by high throughput, small delay, and low packet loss. A larger transmission radius increases the probability of finding a receiver with large progress, but simultaneously increases the probability of collision with other transmissions. Transmission range and the expected progress are pair of design parameters. A short-range transmission is preferred in terms of successful transmission because its avoid collision at the receiver. Long transmission range is favourable in term of: i- it moves a packet the maximum it can in one hop in successful transmission, and ii- the high probability to find a receiver candidate in the progression direction. In this paper, a theoretical model to analyse the one hop throughput with regular structure operating under the CSMA/CA access protocol in wireless ad hoc networks is proposed. We show how we can maximize mean packet progress and mean density of information transport by optimizing the transmission probability and the transmission range. Numerical results show that we can find an optimal transmission range to achieve the highest throughput. An optimal transmission range is essential to limit the energy dissipation on the mobile devices.
{"title":"Analytical Approach to Maximize Throughput in Wireless Ad Hoc Networks","authors":"K. Mnif, Asma Sellami","doi":"10.1109/CNSR.2010.59","DOIUrl":"https://doi.org/10.1109/CNSR.2010.59","url":null,"abstract":"The main concerns of network performance are throughput, end-to-end packet delay and packet loss. A high-performance network is characterized by high throughput, small delay, and low packet loss. A larger transmission radius increases the probability of finding a receiver with large progress, but simultaneously increases the probability of collision with other transmissions. Transmission range and the expected progress are pair of design parameters. A short-range transmission is preferred in terms of successful transmission because its avoid collision at the receiver. Long transmission range is favourable in term of: i- it moves a packet the maximum it can in one hop in successful transmission, and ii- the high probability to find a receiver candidate in the progression direction. In this paper, a theoretical model to analyse the one hop throughput with regular structure operating under the CSMA/CA access protocol in wireless ad hoc networks is proposed. We show how we can maximize mean packet progress and mean density of information transport by optimizing the transmission probability and the transmission range. Numerical results show that we can find an optimal transmission range to achieve the highest throughput. An optimal transmission range is essential to limit the energy dissipation on the mobile devices.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127119559","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}
Guthemberg Silvestre, S. Fernandes, C. Kamienski, D. Sadok
For almost a decade, Peer-to-Peer (P2P) traffic have been putting pressure on network operators. Taking actions to control P2P traffic is a daunting task. In this paper, we present a comprehensive framework for the identification of P2P traffic based on information-theoretic techniques. Despite the inherent difficulty to single out such applications, our methodology is able to successfully identify P2P traffic using a set of communication patterns or profiles. We show that profiles built on the observation of traffic volume are more accurate than those using the number of flows.
{"title":"Most Wanted Internet Applications: A Framework for P2P Identification","authors":"Guthemberg Silvestre, S. Fernandes, C. Kamienski, D. Sadok","doi":"10.1109/CNSR.2010.64","DOIUrl":"https://doi.org/10.1109/CNSR.2010.64","url":null,"abstract":"For almost a decade, Peer-to-Peer (P2P) traffic have been putting pressure on network operators. Taking actions to control P2P traffic is a daunting task. In this paper, we present a comprehensive framework for the identification of P2P traffic based on information-theoretic techniques. Despite the inherent difficulty to single out such applications, our methodology is able to successfully identify P2P traffic using a set of communication patterns or profiles. We show that profiles built on the observation of traffic volume are more accurate than those using the number of flows.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114495196","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 is an investigation into non--uniform sampling and its effects when correction is not available. First, a mathematical model is put forth, which a physical implementation was then based on. A comparison of both the theoretical and practical implementation took place, and it was found that the mathematical model accurately predicted the results. The mathematical model used statistics to predict the output variance given an input variance; the output variance was found to have half the input variance. It was found that the amount of noise added to the channel increases linearly with the length of the shift register until it reaches a maximum value.
{"title":"Analysis and Implementation of a Simple Method to Add Noise to a Channel Using Non-uniform Sampling","authors":"Brandon C. Brown, M. Kaye, B. Petersen","doi":"10.1109/CNSR.2010.50","DOIUrl":"https://doi.org/10.1109/CNSR.2010.50","url":null,"abstract":"This paper is an investigation into non--uniform sampling and its effects when correction is not available. First, a mathematical model is put forth, which a physical implementation was then based on. A comparison of both the theoretical and practical implementation took place, and it was found that the mathematical model accurately predicted the results. The mathematical model used statistics to predict the output variance given an input variance; the output variance was found to have half the input variance. It was found that the amount of noise added to the channel increases linearly with the length of the shift register until it reaches a maximum value.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127932646","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 this paper, we investigate the problem of schedulingand resource allocation for LTE Single Cell Uplink systemswhich use Single Carrier Frequency Division MultipleAccess (SC-FDMA). SC-FDMA (L-FDMA scheme) has particularscheduling requirements such as limited power consumption and contiguous resource block constraints. This last requirement has been seldom taken into account in the previous scheduling and resource allocation algorithms. In addition, there is also an end-to-end delay requirement concern, which has not yet been investigated in conjunction with block contiguity constraints, in the LTE Uplink scheduling and resource allocation literature.The end-to-end delay is a significant quality of service (QoS) matter; taking into account that it has a notable impact on the number of users that can be effectively served.We provide two new scheduling algorithms that, in additionto the channel contiguity constraint, take also into account the end-to-end delay constraint. Simulations are conducted on traffic instances with up to 144 users and results are compared with two very recently proposed algorithms. Results show that we increase by approximately a factor of 3, the user capacity of the system relative to systems that does not include the end-to-end delay constraint, without sacrificing the user fairness.
{"title":"Scheduling and Resource Allocation in LTE Uplink with a Delay Requirement","authors":"Oscar Delgado, B. Jaumard","doi":"10.1109/CNSR.2010.33","DOIUrl":"https://doi.org/10.1109/CNSR.2010.33","url":null,"abstract":"In this paper, we investigate the problem of schedulingand resource allocation for LTE Single Cell Uplink systemswhich use Single Carrier Frequency Division MultipleAccess (SC-FDMA). SC-FDMA (L-FDMA scheme) has particularscheduling requirements such as limited power consumption and contiguous resource block constraints. This last requirement has been seldom taken into account in the previous scheduling and resource allocation algorithms. In addition, there is also an end-to-end delay requirement concern, which has not yet been investigated in conjunction with block contiguity constraints, in the LTE Uplink scheduling and resource allocation literature.The end-to-end delay is a significant quality of service (QoS) matter; taking into account that it has a notable impact on the number of users that can be effectively served.We provide two new scheduling algorithms that, in additionto the channel contiguity constraint, take also into account the end-to-end delay constraint. Simulations are conducted on traffic instances with up to 144 users and results are compared with two very recently proposed algorithms. Results show that we increase by approximately a factor of 3, the user capacity of the system relative to systems that does not include the end-to-end delay constraint, without sacrificing the user fairness.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127962757","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}
Shihyon Park, B. Matthews, Danny D'Amours, W. McIver
Video-based communications are becoming more important within domains, such as health care, that have stringent security and privacy requirements for data. VPN-based encryption is a now common part of organizational security architectures. It is expected that the time required to perform encryption at a VPN concentrator and decryption at the client side video may add significant overhead to the transmission of real-time video, which is already delay-sensitive. The real impacts of this overhead on Quality of user Experience are not well-understood. This paper describes experimental methods for measuring the network-level impacts of virtual private network (VPN) encryption on real-time video in wired and wireless networks. It also presents experimental results using these methods. This paper concludes that VPN-based encryption introduces significant latency to real-time video and that further analysis is warranted to characterize the transitive impacts of such latency on the quality of user experience
{"title":"Characterizing the Impacts of VPN Security Models on Streaming Video","authors":"Shihyon Park, B. Matthews, Danny D'Amours, W. McIver","doi":"10.1109/CNSR.2010.60","DOIUrl":"https://doi.org/10.1109/CNSR.2010.60","url":null,"abstract":"Video-based communications are becoming more important within domains, such as health care, that have stringent security and privacy requirements for data. VPN-based encryption is a now common part of organizational security architectures. It is expected that the time required to perform encryption at a VPN concentrator and decryption at the client side video may add significant overhead to the transmission of real-time video, which is already delay-sensitive. The real impacts of this overhead on Quality of user Experience are not well-understood. This paper describes experimental methods for measuring the network-level impacts of virtual private network (VPN) encryption on real-time video in wired and wireless networks. It also presents experimental results using these methods. This paper concludes that VPN-based encryption introduces significant latency to real-time video and that further analysis is warranted to characterize the transitive impacts of such latency on the quality of user experience","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130443951","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}
E. Fgee, Abdoelbari Elalo, W. Phillips, A. Elhounie
This paper deals with the routing optimization in IPV6networks. It's the key processes of traffic engineering andnetwork planning.Routing optimization provides a means to balance thetraffic load in the network with the goal to improve thequality of service. The main objective of our routingoptimization procedures is the minimization of the end-to-end delay, which is the total time of an individual packetto transfer from source to destination node. By optimizedone of router's functions, this function is the packetclassification. This work is done modify the packetclassification operation in the router architecture bymaking it based on two tuples (source address and flowlabel)instead of the regular five tuples to classify thecoming packets.Finally, to test and compare the performance ofour algorithm, we used the network simulator NS-2,version 2.29. The simulation results indicate that theproposed algorithm indeed helps to minimize the end-toenddelay as a result of router optimization.
{"title":"Using Routing Optimization in Next Generation Network to Achieve High QoS","authors":"E. Fgee, Abdoelbari Elalo, W. Phillips, A. Elhounie","doi":"10.1109/CNSR.2010.41","DOIUrl":"https://doi.org/10.1109/CNSR.2010.41","url":null,"abstract":"This paper deals with the routing optimization in IPV6networks. It's the key processes of traffic engineering andnetwork planning.Routing optimization provides a means to balance thetraffic load in the network with the goal to improve thequality of service. The main objective of our routingoptimization procedures is the minimization of the end-to-end delay, which is the total time of an individual packetto transfer from source to destination node. By optimizedone of router's functions, this function is the packetclassification. This work is done modify the packetclassification operation in the router architecture bymaking it based on two tuples (source address and flowlabel)instead of the regular five tuples to classify thecoming packets.Finally, to test and compare the performance ofour algorithm, we used the network simulator NS-2,version 2.29. The simulation results indicate that theproposed algorithm indeed helps to minimize the end-toenddelay as a result of router optimization.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"295 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115826142","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}
N. Ababneh, Anastasios Viglas, S. Selvadurai, N. Boukhatem
The main design challenge for wireless sensor network solutions is energy efficiency to prolong the network operable lifetime. Since most energy is spent for radio communications, an effective approach for energy conservation is scheduling sleep intervals for extraneous nodes, while the remaining nodes stay active to provide continuous service. Assuming node position information is unavailable we propose an algorithm to construct a sparse spanner network topology for these networks. It uses two-hop neighborhood information to select a subset of nodes to be active among all nodes in the neighborhood. Each node in the network selects its own set of active neighbors from among its one-hop neighbors. This set is determined such that it covers all two-hop neighbors. Our proposed algorithm is proved to achieve several desirable properties on both Euclidean and general weighted graphs: (1) the resulting graph is symmetric and connected; (2) the resulting graph also exhibits good spanner properties for both distance/energy and hops; (3) it is constructed locally in a fully distributed fashion; (4) we prove that on the average-case unit disk graphs, the resulting topology features the bounded degree property; (5) finally, the computation cost of our algorithm is at most O(n^3 ), and the communication cost is bounded by O(n^2 ).
{"title":"A Topology Control Algorithm with Good Spanner Properties for Wireless Sensor Networks","authors":"N. Ababneh, Anastasios Viglas, S. Selvadurai, N. Boukhatem","doi":"10.1109/CNSR.2010.37","DOIUrl":"https://doi.org/10.1109/CNSR.2010.37","url":null,"abstract":"The main design challenge for wireless sensor network solutions is energy efficiency to prolong the network operable lifetime. Since most energy is spent for radio communications, an effective approach for energy conservation is scheduling sleep intervals for extraneous nodes, while the remaining nodes stay active to provide continuous service. Assuming node position information is unavailable we propose an algorithm to construct a sparse spanner network topology for these networks. It uses two-hop neighborhood information to select a subset of nodes to be active among all nodes in the neighborhood. Each node in the network selects its own set of active neighbors from among its one-hop neighbors. This set is determined such that it covers all two-hop neighbors. Our proposed algorithm is proved to achieve several desirable properties on both Euclidean and general weighted graphs: (1) the resulting graph is symmetric and connected; (2) the resulting graph also exhibits good spanner properties for both distance/energy and hops; (3) it is constructed locally in a fully distributed fashion; (4) we prove that on the average-case unit disk graphs, the resulting topology features the bounded degree property; (5) finally, the computation cost of our algorithm is at most O(n^3 ), and the communication cost is bounded by O(n^2 ).","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128393730","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}
Future envisions universal and uninterrupted access to information owing to the widespread use of heterogeneous wireless technologies. The integration of heterogeneous wireless technologies and existence of multi-mode terminals enable users get associated to the best available networks according to user preferences over different application specific requirements, prices and network technologies. In this paper we present the user-centric network selection decision mechanism, where negotiation between users and network operators is carried out using game-theoretic approach. We model the utility functions of users and network operators in terms of offered prices and service quality. The proposed approach builds on IEEE 802.21standard. Session Initiation Protocol(SIP) and Mobile Internet Protocol (MIPv6) based flow management solutions are given, the later approach is implemented using OPNET modeller simulator. The performance of our approachis compared with Long-term contractual approach in termsof users throughput, users’ cost, operators’ revenue and call blocking probability.
{"title":"Game-Theory Based User Centric Network Selection with Media Independent Handover Services and Flow Management","authors":"M. A. Khan, U. Toseef, Stefan Marx, C. Görg","doi":"10.1109/CNSR.2010.40","DOIUrl":"https://doi.org/10.1109/CNSR.2010.40","url":null,"abstract":"Future envisions universal and uninterrupted access to information owing to the widespread use of heterogeneous wireless technologies. The integration of heterogeneous wireless technologies and existence of multi-mode terminals enable users get associated to the best available networks according to user preferences over different application specific requirements, prices and network technologies. In this paper we present the user-centric network selection decision mechanism, where negotiation between users and network operators is carried out using game-theoretic approach. We model the utility functions of users and network operators in terms of offered prices and service quality. The proposed approach builds on IEEE 802.21standard. Session Initiation Protocol(SIP) and Mobile Internet Protocol (MIPv6) based flow management solutions are given, the later approach is implemented using OPNET modeller simulator. The performance of our approachis compared with Long-term contractual approach in termsof users throughput, users’ cost, operators’ revenue and call blocking probability.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130942494","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}
Mobile ad hoc network (MANET) can be the best option in developing seamless communication environment in various application scenarios where there is no any pre-defined infrastructure. A mobility model which represents movement behavior of considered application scenarios should incorporate important features that may change characteristics of mobile nodes. In most of the cases, mobile nodes used to move along predefined paths toward their destination. We propose a new mobility model which represents movement of mobile nodes in case of pre-defined structured area including attraction points to incorporate realistic behavior. We simulate performance of Ad hoc on-demand distance vector (AODV) routing protocol varying speed, load and node density. In terms of performances, average end-to-end delay is less in case of proposed mobility model. However, packet delivery ratio is found lower compare to random way point. The goal of our proposal is to model user’s realistic behavior in conventional routing protocols.
{"title":"Mobility Model for User's Realistic Behavior in Mobile Ad Hoc Network","authors":"Shiddhartha Raj Bhandari, G. Lee, N. Crespi","doi":"10.1109/CNSR.2010.27","DOIUrl":"https://doi.org/10.1109/CNSR.2010.27","url":null,"abstract":"Mobile ad hoc network (MANET) can be the best option in developing seamless communication environment in various application scenarios where there is no any pre-defined infrastructure. A mobility model which represents movement behavior of considered application scenarios should incorporate important features that may change characteristics of mobile nodes. In most of the cases, mobile nodes used to move along predefined paths toward their destination. We propose a new mobility model which represents movement of mobile nodes in case of pre-defined structured area including attraction points to incorporate realistic behavior. We simulate performance of Ad hoc on-demand distance vector (AODV) routing protocol varying speed, load and node density. In terms of performances, average end-to-end delay is less in case of proposed mobility model. However, packet delivery ratio is found lower compare to random way point. The goal of our proposal is to model user’s realistic behavior in conventional routing protocols.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125469067","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}
We focus on the interference between mobile stations as they attempt to gain access to an OFDMA-based WiMAX/IEEE 802.16 network. We propose a set of strategies that enable base stations to 1) reduce or eliminate the interference between emergency and non-emergency mobile stations and 2) provide prioritized access to emergency mobile stations. Our strategies include introducing a sliding contention window, redistribution of ranging codes and the abilityof base stations to delay the entry process of any mobile station. We give an analysis of our strategies and some simulated results.
{"title":"Prioritized Access for Emergency Stations in Next Generation Broadband Wireless Networks","authors":"Paul Boone, M. Barbeau, E. Kranakis","doi":"10.1109/CNSR.2010.35","DOIUrl":"https://doi.org/10.1109/CNSR.2010.35","url":null,"abstract":"We focus on the interference between mobile stations as they attempt to gain access to an OFDMA-based WiMAX/IEEE 802.16 network. We propose a set of strategies that enable base stations to 1) reduce or eliminate the interference between emergency and non-emergency mobile stations and 2) provide prioritized access to emergency mobile stations. Our strategies include introducing a sliding contention window, redistribution of ranging codes and the abilityof base stations to delay the entry process of any mobile station. We give an analysis of our strategies and some simulated results.","PeriodicalId":208564,"journal":{"name":"2010 8th Annual Communication Networks and Services Research Conference","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114805023","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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