Pub Date : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594875
D. Salyers, A. Striegel, C. Poellabauer
Wireless enabled devices are ubiquitous in todaypsilas computing environment. Businesses, universities, and home users alike are taking advantage of the easy deployment of wireless devices to provide network connectivity without the expense associated with wired connections. Unfortunately, the wireless medium is inherently unreliable resulting in significant work having been performed to better understand the characteristics of the wireless environment. Notably, many works attribute the primary source of wireless losses to errors in the physical medium. In contrast, our work shows that the wireless device itself plays a significant role in 802.11 packet loss. In our experiments, we found that the correlation of loss between multiple closely located (within one lambda) receivers is low with the majority of loss instances only occurring at one of the receivers. We conducted extensive experiments on the individual loss characteristics of five common wireless cards, showing that while the cards behave similarly on the macro-level (e.g. similar overall loss rates), the cards perform quite differently on the micro-level (e.g. burstiness, correlation, and consistency).
{"title":"Wireless reliability: Rethinking 802.11 packet loss","authors":"D. Salyers, A. Striegel, C. Poellabauer","doi":"10.1109/WOWMOM.2008.4594875","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594875","url":null,"abstract":"Wireless enabled devices are ubiquitous in todaypsilas computing environment. Businesses, universities, and home users alike are taking advantage of the easy deployment of wireless devices to provide network connectivity without the expense associated with wired connections. Unfortunately, the wireless medium is inherently unreliable resulting in significant work having been performed to better understand the characteristics of the wireless environment. Notably, many works attribute the primary source of wireless losses to errors in the physical medium. In contrast, our work shows that the wireless device itself plays a significant role in 802.11 packet loss. In our experiments, we found that the correlation of loss between multiple closely located (within one lambda) receivers is low with the majority of loss instances only occurring at one of the receivers. We conducted extensive experiments on the individual loss characteristics of five common wireless cards, showing that while the cards behave similarly on the macro-level (e.g. similar overall loss rates), the cards perform quite differently on the micro-level (e.g. burstiness, correlation, and consistency).","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115633014","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594880
Sungjun Kim, Doohyun Ko, Sunshin An
A large number of RFID system support location based service. This RFID Location System based on the general purposed geographic location code supports monitoring of the RFID tags in real time effectively. To identify the RFID tags, we allocate the general purposed geographic location code for each region. Throughout this system, the distribution and services related with RFID can easily manage the objects.
{"title":"Geographical location based RFID tracking system","authors":"Sungjun Kim, Doohyun Ko, Sunshin An","doi":"10.1109/WOWMOM.2008.4594880","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594880","url":null,"abstract":"A large number of RFID system support location based service. This RFID Location System based on the general purposed geographic location code supports monitoring of the RFID tags in real time effectively. To identify the RFID tags, we allocate the general purposed geographic location code for each region. Throughout this system, the distribution and services related with RFID can easily manage the objects.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123947264","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594868
Kyle O'Brien, D. Salyers, A. Striegel, C. Poellabauer
Even though their capacities are still orders of magnitude lower than those of hard disks, flash storage systems are rapidly gaining importance in energy-constrained systems. This paper focuses on USB flash drives, which can provide portable storage to mobile systems or storage to systems that otherwise do not have persistent storage opportunities (e.g., low-power sensor devices). The paper presents studies relating to power consumption, energy overheads and benefits, and performance impacts of USB flash drives. The key insights obtained from these experiments are that (i) read/write costs are not significantly greater than idle costs and (ii) the size of the flash itself has only limited bearing on energy consumption.
{"title":"Power and performance characteristics of USB flash drives","authors":"Kyle O'Brien, D. Salyers, A. Striegel, C. Poellabauer","doi":"10.1109/WOWMOM.2008.4594868","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594868","url":null,"abstract":"Even though their capacities are still orders of magnitude lower than those of hard disks, flash storage systems are rapidly gaining importance in energy-constrained systems. This paper focuses on USB flash drives, which can provide portable storage to mobile systems or storage to systems that otherwise do not have persistent storage opportunities (e.g., low-power sensor devices). The paper presents studies relating to power consumption, energy overheads and benefits, and performance impacts of USB flash drives. The key insights obtained from these experiments are that (i) read/write costs are not significantly greater than idle costs and (ii) the size of the flash itself has only limited bearing on energy consumption.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121195060","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594826
R. V. Prasad, Yonghua Li, M. Jacobsson, A. Lo, I. Niemegeers
With the advent of miniaturization and higher computing capabilities of wireless devices, there is an exponential rise in the number of devices such as personal digital assistants, etc. Application development for these devices is the main focus for many device manufacturers and software developers. The applications developed need to be tested and tried before releasing it to the market. There are cross-compilers to produce the binary files of the software applications that can run on these devices. However, it is rather difficult for developers to test it on the actual devices every time a change is made in the program. Further, a wireless network infrastructure should also be in place for testing. To expedite application development FEW-PNets - a Framework for Emulation of Wireless Personal Networks is proposed. It is a networked application to emulate a Personal Network (PN) owned by a person. It supports emulation of the most functions of PNs. We explain our model by emulating simple PN devices. In this article we elucidate the concepts, advantages, application domains and limitations of FEW-PNets.
{"title":"FEW-PNets - A framework for emulation of wireless personal networks","authors":"R. V. Prasad, Yonghua Li, M. Jacobsson, A. Lo, I. Niemegeers","doi":"10.1109/WOWMOM.2008.4594826","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594826","url":null,"abstract":"With the advent of miniaturization and higher computing capabilities of wireless devices, there is an exponential rise in the number of devices such as personal digital assistants, etc. Application development for these devices is the main focus for many device manufacturers and software developers. The applications developed need to be tested and tried before releasing it to the market. There are cross-compilers to produce the binary files of the software applications that can run on these devices. However, it is rather difficult for developers to test it on the actual devices every time a change is made in the program. Further, a wireless network infrastructure should also be in place for testing. To expedite application development FEW-PNets - a Framework for Emulation of Wireless Personal Networks is proposed. It is a networked application to emulate a Personal Network (PN) owned by a person. It supports emulation of the most functions of PNs. We explain our model by emulating simple PN devices. In this article we elucidate the concepts, advantages, application domains and limitations of FEW-PNets.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123466680","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594876
M. Soltan, Inkwon Hwang, Massoud Pedram
With power efficiency and lifetime awareness becoming critical design concerns in wireless sensor networks (WSN), it has become essential to exploit the physical layer characteristics at the system deployment stage. This paper focuses on how certain physical layer attributes can affect both the lifetime and the end-to-end delay in a hierarchical WSN. We present a heterogeneous modulation scheme and report its impact on the spatial distribution of energy dissipation and the resulting network lifetime. Moreover, we study how this heterogeneous modulation scheme affects the end-to-end delay due to inherent trade-offs in power efficiency and bandwidth efficiency of the different modulation schemes.
{"title":"Heterogeneous modulation for trading-off energy balancing with bandwidth efficiency in hierarchical sensor networks","authors":"M. Soltan, Inkwon Hwang, Massoud Pedram","doi":"10.1109/WOWMOM.2008.4594876","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594876","url":null,"abstract":"With power efficiency and lifetime awareness becoming critical design concerns in wireless sensor networks (WSN), it has become essential to exploit the physical layer characteristics at the system deployment stage. This paper focuses on how certain physical layer attributes can affect both the lifetime and the end-to-end delay in a hierarchical WSN. We present a heterogeneous modulation scheme and report its impact on the spatial distribution of energy dissipation and the resulting network lifetime. Moreover, we study how this heterogeneous modulation scheme affects the end-to-end delay due to inherent trade-offs in power efficiency and bandwidth efficiency of the different modulation schemes.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125085372","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594925
Luis E. Palafox, J. A. García-Macías
Monitoring the environment is one of the main applications of wireless sensor networks. Given that these networks are densely populated and that local variations in the environmental variables are small, a large amount of redundant data is generated by sensor nodes. In this paper we present a protocol for data dissemination in hierarchical sensor networks that integrates security and reduces communication overhead by removing data redundancy from the network. Furthermore, we show that by using our protocol we can provide security to the network without spending additional energy resources, particularly when we are dealing with high levels of redundancy.
{"title":"Secure data recollection for redundantly deployed wireless sensor networks","authors":"Luis E. Palafox, J. A. García-Macías","doi":"10.1109/WOWMOM.2008.4594925","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594925","url":null,"abstract":"Monitoring the environment is one of the main applications of wireless sensor networks. Given that these networks are densely populated and that local variations in the environmental variables are small, a large amount of redundant data is generated by sensor nodes. In this paper we present a protocol for data dissemination in hierarchical sensor networks that integrates security and reduces communication overhead by removing data redundancy from the network. Furthermore, we show that by using our protocol we can provide security to the network without spending additional energy resources, particularly when we are dealing with high levels of redundancy.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"40 7 Suppl 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126176399","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594920
Lei Tang, X. Hong, Susan V. Vrbsky
The privacy of wireless communications is becoming an important issue due to the open nature of wireless medium. Much research work has been proposed to address the anonymity of communicating parties, the location privacy of the message source and destination, and the privacy of the network routing paths. However, with the advent of new radio identification and localization techniques, more advanced privacy attacks are possible. We describe a new privacy attack in which the adversary tries to infer the itineraries of the nodes in the network. To protect itinerary privacy, we design an algorithm, called the Delta-mobility camouflaging algorithm, which can be applied upon any mobility model by changing the original motion segments into Delta-shaped camouflaging paths. Our analysis results show that the Delta-mobility camouflaging algorithm is cost-effective, which in most cases decreases the itinerary exposure probability more than 80% at a cost of less than 3% extra travel distance.
{"title":"Camouflaging mobility for itinerary privacy in mobile ad-hoc networks","authors":"Lei Tang, X. Hong, Susan V. Vrbsky","doi":"10.1109/WOWMOM.2008.4594920","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594920","url":null,"abstract":"The privacy of wireless communications is becoming an important issue due to the open nature of wireless medium. Much research work has been proposed to address the anonymity of communicating parties, the location privacy of the message source and destination, and the privacy of the network routing paths. However, with the advent of new radio identification and localization techniques, more advanced privacy attacks are possible. We describe a new privacy attack in which the adversary tries to infer the itineraries of the nodes in the network. To protect itinerary privacy, we design an algorithm, called the Delta-mobility camouflaging algorithm, which can be applied upon any mobility model by changing the original motion segments into Delta-shaped camouflaging paths. Our analysis results show that the Delta-mobility camouflaging algorithm is cost-effective, which in most cases decreases the itinerary exposure probability more than 80% at a cost of less than 3% extra travel distance.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"164 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127348352","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594817
Dongmyoung Kim, Hua Cai, Minsoo Na, Sunghyun Choi
WiBro (Wireless Broadband) is a Korean version of Mobile WiMAX/IEEE 802.16e system, which is designed for mobile broadband wireless access. Being a subset of IEEE 802.16e, WiBro employs orthogonal frequency division multiple access (OFDMA) and time division duplexing (TDD) schemes operating at 2.3 GHz bands. In mid 2006, the world first commercial Mobile WiMAX service, based on WiBro specification, started in Seoul, Korea. In this paper, we analyze the performance of commercial WiBro networks through traffic measurements. Many experiments are conducted in the various environments. We analyze the link capacity when the user datagram protocol (UDP) packets from multiple users fully utilize wireless links. We also analyze goodput performance with transmission control protocol (TCP) as well as round trip time performance. The measured performances are compared with those of HSDPA (High-Speed Downlink Packet Access) which is a competing system of Mobile WiMAX. We found that the RTTs of WiBro and HSDPA are very large compared with conventional data networks, e.g., Ethernet or Wireless LANs. Furthermore, it is shown that the user-perceived performance is limited by such long round trip times when TCP is utilized. It motivates us to improve round trip time performance of WiBro system. Finally, we analyze the VoIP performance and the performance when the user moves around the whole city.
{"title":"Performance measurement over Mobile WiMAX/IEEE 802.16e network","authors":"Dongmyoung Kim, Hua Cai, Minsoo Na, Sunghyun Choi","doi":"10.1109/WOWMOM.2008.4594817","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594817","url":null,"abstract":"WiBro (Wireless Broadband) is a Korean version of Mobile WiMAX/IEEE 802.16e system, which is designed for mobile broadband wireless access. Being a subset of IEEE 802.16e, WiBro employs orthogonal frequency division multiple access (OFDMA) and time division duplexing (TDD) schemes operating at 2.3 GHz bands. In mid 2006, the world first commercial Mobile WiMAX service, based on WiBro specification, started in Seoul, Korea. In this paper, we analyze the performance of commercial WiBro networks through traffic measurements. Many experiments are conducted in the various environments. We analyze the link capacity when the user datagram protocol (UDP) packets from multiple users fully utilize wireless links. We also analyze goodput performance with transmission control protocol (TCP) as well as round trip time performance. The measured performances are compared with those of HSDPA (High-Speed Downlink Packet Access) which is a competing system of Mobile WiMAX. We found that the RTTs of WiBro and HSDPA are very large compared with conventional data networks, e.g., Ethernet or Wireless LANs. Furthermore, it is shown that the user-perceived performance is limited by such long round trip times when TCP is utilized. It motivates us to improve round trip time performance of WiBro system. Finally, we analyze the VoIP performance and the performance when the user moves around the whole city.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127456801","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594915
Kai Kamphenkel, M. Blank, Jens Bauer, G. Carle
This paper presents an analysis of the potential of adaptive encryption of streaming video data over 3G networks. The results obtained promote the design of a network component (the so called ldquointelligent networkrdquo) that facilitates the secure real-time transmission of video data. Case studies involving the sensitive area of telemedicine can be implemented by means of this component. The transport layer protocol SCTP is the basis for technical realization, which has interesting features and extensions. The combination of these features and the management of the intelligent network allows the implementation of sensitive applications.
{"title":"Adaptive encryption for the realization of real-time transmission of sensitive medical video streams","authors":"Kai Kamphenkel, M. Blank, Jens Bauer, G. Carle","doi":"10.1109/WOWMOM.2008.4594915","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594915","url":null,"abstract":"This paper presents an analysis of the potential of adaptive encryption of streaming video data over 3G networks. The results obtained promote the design of a network component (the so called ldquointelligent networkrdquo) that facilitates the secure real-time transmission of video data. Case studies involving the sensitive area of telemedicine can be implemented by means of this component. The transport layer protocol SCTP is the basis for technical realization, which has interesting features and extensions. The combination of these features and the management of the intelligent network allows the implementation of sensitive applications.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131643474","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 : 2008-06-23DOI: 10.1109/WOWMOM.2008.4594822
F. Shaikh, Abdelmajid Khelil, N. Suri
Several proposals describing transport layer protocols for sensor networks appear in the literature. As each proposal is typically evaluated in the context of carefully selected parameters and scenarios, the benefits can be subjective. Also, given the limited details available of different proposals, it is difficult for developers of sensor network applications to select from the range of alternative transport protocols. This paper develops a common basis for evaluation of varied proposals. We first classify and review the existing protocols and evaluate them by measuring their performance in terms of responsiveness and efficiency in a conformal simulation environment and for a wide range of operational conditions. Common sources of poor performance are identified. Based on this experience, a set of design principles for the designers of applications and future transport protocols is presented.
{"title":"A comparative study of data transport protocols in wireless sensor networks","authors":"F. Shaikh, Abdelmajid Khelil, N. Suri","doi":"10.1109/WOWMOM.2008.4594822","DOIUrl":"https://doi.org/10.1109/WOWMOM.2008.4594822","url":null,"abstract":"Several proposals describing transport layer protocols for sensor networks appear in the literature. As each proposal is typically evaluated in the context of carefully selected parameters and scenarios, the benefits can be subjective. Also, given the limited details available of different proposals, it is difficult for developers of sensor network applications to select from the range of alternative transport protocols. This paper develops a common basis for evaluation of varied proposals. We first classify and review the existing protocols and evaluate them by measuring their performance in terms of responsiveness and efficiency in a conformal simulation environment and for a wide range of operational conditions. Common sources of poor performance are identified. Based on this experience, a set of design principles for the designers of applications and future transport protocols is presented.","PeriodicalId":346269,"journal":{"name":"2008 International Symposium on a World of Wireless, Mobile and Multimedia Networks","volume":"22 28","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132545474","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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