In this paper, we propose a cross-layer optimization framework to jointly design the spectrum sharing and flow routing with the interference considerations in cognitive radio networks. Given multiple traffic demands from different source nodes to destination nodes, we formulate an optimization problem in the form of mixed integer linear programming (MILP) to provide a fair routing. Different from the existing work, we consider bi-directional links because we believe the link level acknowledgements in an ad-hoc network are a must. For traffic routing we allow multi-path for each traffic demand. Numerical results show that the spectrum sharing among the secondary users is interference-free and a fair routing is guaranteed for different traffic demands.
{"title":"Joint Spectrum Sharing and Fair Routing in Cognitive Radio Networks","authors":"M. Ma, D. Tsang","doi":"10.1109/CCNC08.2007.225","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.225","url":null,"abstract":"In this paper, we propose a cross-layer optimization framework to jointly design the spectrum sharing and flow routing with the interference considerations in cognitive radio networks. Given multiple traffic demands from different source nodes to destination nodes, we formulate an optimization problem in the form of mixed integer linear programming (MILP) to provide a fair routing. Different from the existing work, we consider bi-directional links because we believe the link level acknowledgements in an ad-hoc network are a must. For traffic routing we allow multi-path for each traffic demand. Numerical results show that the spectrum sharing among the secondary users is interference-free and a fair routing is guaranteed for different traffic demands.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117014507","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 a part of the GREAT project (Galileo receiver for the mass market) research and development activities focused on GNSS mass market receivers for handset terminals have been carried out. In this context, ACORDE is developing a RF subsystem, able to operate with Galileo and GPS satellite signals in the presence of the major 2 G/3 G cellular signals or other assistance technology, and investigating the multiband approach. The key focus is on a highly integrated radio front-end (FE) suitable for use within the mobile phone environment for location based services, satisfying the basic requirements for a mass market receiver such as low cost, low footprint, good accuracy, low power consumption and high sensitivity. The target is a Galileo E1/E5A and GPS L1/L5 dual-system dual band GNSS receiver. This paper will discuss the RF system level design issues for such type of receiver and the preliminary results obtained for the first prototypes of a custom MMIC chipset developed in the frame of the project.
{"title":"Dual-Band RF Front-End Solution for Hybrid Galileo/GPS Mass Market Receivers","authors":"M. Detratti, E. López, E. Pérez, R. Palacio","doi":"10.1109/CCNC08.2007.140","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.140","url":null,"abstract":"As a part of the GREAT project (Galileo receiver for the mass market) research and development activities focused on GNSS mass market receivers for handset terminals have been carried out. In this context, ACORDE is developing a RF subsystem, able to operate with Galileo and GPS satellite signals in the presence of the major 2 G/3 G cellular signals or other assistance technology, and investigating the multiband approach. The key focus is on a highly integrated radio front-end (FE) suitable for use within the mobile phone environment for location based services, satisfying the basic requirements for a mass market receiver such as low cost, low footprint, good accuracy, low power consumption and high sensitivity. The target is a Galileo E1/E5A and GPS L1/L5 dual-system dual band GNSS receiver. This paper will discuss the RF system level design issues for such type of receiver and the preliminary results obtained for the first prototypes of a custom MMIC chipset developed in the frame of the project.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116381871","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}
Youngju Do, S. Yoon, Taekyu Kim, K. Pyun, Sin-Chong Park
This paper proposes a software based parallel CRC (Cyclic Redundancy Check) algorithm called 'N-byte RCC (Repetition of Computation and Combination)''. This algorithm is the iterative process of message computation by the 'slicing-by-4' and combination through the 'zero block lookup tables'. This algorithm can parallelize the CRC calculation with any number of processors. In order to verify the performance of our algorithm, we employ two different communication architectures; the single bus architecture and the 1-star topology NoC (Network on Chip) architecture. With respect to those architectures, we explore our parallel algorithm by using TLM (Transaction Level Model). From the simulation results, we present that the proposed parallel CRC algorithm with BUS and NoC architectures reduces the processing time by 28 percent and 38 percent, respectively, compared to the 'slicing-by-8' which is the fastest algorithms among other software based algorithms. Furthermore, the 1-star NoC architecture of the parallel CRC shows higher performance than the single bus architecture regardless of the number of processors.
{"title":"High-Speed Parallel Architecture for Software-Based CRC","authors":"Youngju Do, S. Yoon, Taekyu Kim, K. Pyun, Sin-Chong Park","doi":"10.1109/CCNC08.2007.23","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.23","url":null,"abstract":"This paper proposes a software based parallel CRC (Cyclic Redundancy Check) algorithm called 'N-byte RCC (Repetition of Computation and Combination)''. This algorithm is the iterative process of message computation by the 'slicing-by-4' and combination through the 'zero block lookup tables'. This algorithm can parallelize the CRC calculation with any number of processors. In order to verify the performance of our algorithm, we employ two different communication architectures; the single bus architecture and the 1-star topology NoC (Network on Chip) architecture. With respect to those architectures, we explore our parallel algorithm by using TLM (Transaction Level Model). From the simulation results, we present that the proposed parallel CRC algorithm with BUS and NoC architectures reduces the processing time by 28 percent and 38 percent, respectively, compared to the 'slicing-by-8' which is the fastest algorithms among other software based algorithms. Furthermore, the 1-star NoC architecture of the parallel CRC shows higher performance than the single bus architecture regardless of the number of processors.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123489853","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 presents the experimental results and analysis of a link variability study for an indoor, stationary 802.11g network in a small office environment. Variability over time of throughput, jitter, and signal-to-noise ratio (SNR) is investigated. The network performance at different indoor locations is analyzed and the relationships of throughput and jitter to the SNR are obtained. The throughput prediction model is compared to other empirical models, showing the similarity between these models. A statistical distribution function of the SNR in this environment is determined, resulting in an SNR higher than 29.83 dB in 90% of the locations, corresponding with a throughput of about 18.25 Mbps and a jitter lower than 1.10 ms.
{"title":"Evaluation of Link Performance of an Indoor 802.11g Network","authors":"J. D. Bruyne, W. Joseph, L. Verloock, L. Martens","doi":"10.1109/CCNC08.2007.101","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.101","url":null,"abstract":"This paper presents the experimental results and analysis of a link variability study for an indoor, stationary 802.11g network in a small office environment. Variability over time of throughput, jitter, and signal-to-noise ratio (SNR) is investigated. The network performance at different indoor locations is analyzed and the relationships of throughput and jitter to the SNR are obtained. The throughput prediction model is compared to other empirical models, showing the similarity between these models. A statistical distribution function of the SNR in this environment is determined, resulting in an SNR higher than 29.83 dB in 90% of the locations, corresponding with a throughput of about 18.25 Mbps and a jitter lower than 1.10 ms.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125850604","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}
With the growing deployments of UMTS/HSDPA and recently WiMAX, the integration of these two broadband radio networks becomes an important challenge. However, the convergence of UTRAN and IEEE 802.16 as a radio access network is still limited. In this paper we propose a simple adaptation in WiMAX to enhance voice over IP support for end to end telephonic applications between UMTS and WiMAX. Our goal is to allow an operator to propose UMTS service via an 802.16 radio access network or UTRAN as well. First, we super-framed the 802.16 frame to enhance AMR codec compatibility. In addition, we use ON/OFF periods detection of voice sources to decrease the bandwidth allocated for the same number of calls. We then take advantage from the WiMAX uplink frame structure and from the loss tolerance of voice. Performance evaluation (analytical and simulation) is given to illustrate the benefits of our proposal.
{"title":"Enhancing MAC IEEE 802.16 Voice Support with Statistical Multiple Access for UMTS Integration","authors":"M. Abdennebi, M. Ibrahim, S. Tohmé","doi":"10.1109/CCNC08.2007.13","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.13","url":null,"abstract":"With the growing deployments of UMTS/HSDPA and recently WiMAX, the integration of these two broadband radio networks becomes an important challenge. However, the convergence of UTRAN and IEEE 802.16 as a radio access network is still limited. In this paper we propose a simple adaptation in WiMAX to enhance voice over IP support for end to end telephonic applications between UMTS and WiMAX. Our goal is to allow an operator to propose UMTS service via an 802.16 radio access network or UTRAN as well. First, we super-framed the 802.16 frame to enhance AMR codec compatibility. In addition, we use ON/OFF periods detection of voice sources to decrease the bandwidth allocated for the same number of calls. We then take advantage from the WiMAX uplink frame structure and from the loss tolerance of voice. Performance evaluation (analytical and simulation) is given to illustrate the benefits of our proposal.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124765701","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}
Conserving power in mobile ad-hoc and sensor networks is a big challenge. Most of the nodes in these networks, in general, are battery powered therefore, an efficient power saving protocol is required to extend the lifetime of such networks. A lot of work has been done and several protocols have been proposed to address this problem. Gossip based protocols, which are based on the results of percolation theory, significantly reduce power consumption with very little implementation overhead. However, not much work has been done to make gossiping battery aware. In this paper we introduce a simple gossip based battery aware sleep protocol. The protocol allows low battery nodes to sleep more, therefore, improves overall network lifetime.
{"title":"A Simple Battery Aware Gossip Based Sleep Protocol for Densely Deployed Ad-Hoc and Sensor Networks","authors":"A. Shukla","doi":"10.1109/ccnc08.2007.169","DOIUrl":"https://doi.org/10.1109/ccnc08.2007.169","url":null,"abstract":"Conserving power in mobile ad-hoc and sensor networks is a big challenge. Most of the nodes in these networks, in general, are battery powered therefore, an efficient power saving protocol is required to extend the lifetime of such networks. A lot of work has been done and several protocols have been proposed to address this problem. Gossip based protocols, which are based on the results of percolation theory, significantly reduce power consumption with very little implementation overhead. However, not much work has been done to make gossiping battery aware. In this paper we introduce a simple gossip based battery aware sleep protocol. The protocol allows low battery nodes to sleep more, therefore, improves overall network lifetime.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129530551","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}
Woonsik Lee, Minh-Viet Nguyen, Jeong Han Jeong, Byungjik Keum, Hwang-Soo Lee
For the next generation wireless communication systems, inter-cell interference (ICI) is the main source of performance degradation in mobile stations, especially, cell-edge mobile stations. This paper presents a novel orthogonal resource allocation algorithm (ORAA) for our proposed system architecture, termed the OFDMA-based cellular wireless system architecture using relays (OCWSAR). By using relays to cover the cell-edge areas and a robust algorithm with priority resource allocation, the ICI of the system is significantly reduced, while the sector frequency reuse factor is maintained at 1. A system-level simulator is developed in a multi-cell/multi-user environment, where the effect of the proposed ORAA can be evaluated precisely in the presence of inter-cell interference (ICI). Furthermore, the simulation results assure that the new system architecture with the associated algorithm yield higher SINR and data throughput for cell-edge users.
{"title":"An Orthogonal Resource Allocation Algorithm to Improve the Performance of OFDMA-Based Cellular Wireless Systems Using Relays","authors":"Woonsik Lee, Minh-Viet Nguyen, Jeong Han Jeong, Byungjik Keum, Hwang-Soo Lee","doi":"10.1109/CCNC08.2007.213","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.213","url":null,"abstract":"For the next generation wireless communication systems, inter-cell interference (ICI) is the main source of performance degradation in mobile stations, especially, cell-edge mobile stations. This paper presents a novel orthogonal resource allocation algorithm (ORAA) for our proposed system architecture, termed the OFDMA-based cellular wireless system architecture using relays (OCWSAR). By using relays to cover the cell-edge areas and a robust algorithm with priority resource allocation, the ICI of the system is significantly reduced, while the sector frequency reuse factor is maintained at 1. A system-level simulator is developed in a multi-cell/multi-user environment, where the effect of the proposed ORAA can be evaluated precisely in the presence of inter-cell interference (ICI). Furthermore, the simulation results assure that the new system architecture with the associated algorithm yield higher SINR and data throughput for cell-edge users.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129750204","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}
Bomjun Kwon, Shane Cho, Sunghwan Min, Heejin Chung, Cheolhun Jo, Ji-Young Kim, Seok-Jae Lee
Shadow 3D is an extended version of Shadow, a GUI middleware for home digital media devices. In addition to Shadow's 2D GUI features, Shadow 3D supports a full range of 3D GUI features including OpenGL-based low-level 3D graphics, 3D object management, and high-level 3D widgets. It also provides a method for seamless integration with legacy 2D GUI applications. In this paper, we describe the Shadow 3D architecture and design, as well as several technical issues related with 3D GUI implementation.
{"title":"Shadow 3D: A 3D GUI Middleware for Home Digital Media Devices","authors":"Bomjun Kwon, Shane Cho, Sunghwan Min, Heejin Chung, Cheolhun Jo, Ji-Young Kim, Seok-Jae Lee","doi":"10.1109/CCNC08.2007.148","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.148","url":null,"abstract":"Shadow 3D is an extended version of Shadow, a GUI middleware for home digital media devices. In addition to Shadow's 2D GUI features, Shadow 3D supports a full range of 3D GUI features including OpenGL-based low-level 3D graphics, 3D object management, and high-level 3D widgets. It also provides a method for seamless integration with legacy 2D GUI applications. In this paper, we describe the Shadow 3D architecture and design, as well as several technical issues related with 3D GUI implementation.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129644781","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 spread of DLNA (digital living network alliance) certified consumer electronics has already started and there are some proposals for communication systems involving two home networks linked via virtual private network (VPN), that aim to use consumer electronics from the Internet. However, those systems have some problems. For example, against the user's wishes, the ITN connection makes all the contents available for other users as well. The user cannot access content because DLNA devices refuse access from outside the home network. In this paper, we propose a new system that expands the interconnection area from a home network to a mobile phone and consumer electronics in other home networks. Furthermore, we evaluate the proposed system by constructing a test bed that includes consumer electronics obtainable at stores.
DLNA (digital living network alliance，数字生活网络联盟)认证的消费电子产品的普及已经开始，并且有人提议通过虚拟专用网(VPN)连接两个家庭网络的通信系统，目的是利用互联网上的消费电子产品。然而，这些系统有一些问题。例如，与用户的意愿相反，ITN连接使所有内容也可供其他用户使用。用户无法访问内容，因为DLNA设备拒绝从家庭网络外部访问。在本文中，我们提出了一种新的系统，将互连区域从家庭网络扩展到其他家庭网络中的移动电话和消费电子产品。此外，我们通过构建一个包括可在商店获得的消费电子产品的试验台来评估所提出的系统。
{"title":"Proposal on Wide Area DLNA Communication System","authors":"S. Motegi, K. Tasaka, A. Idoue, H. Horiuchi","doi":"10.1109/CCNC08.2007.59","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.59","url":null,"abstract":"The spread of DLNA (digital living network alliance) certified consumer electronics has already started and there are some proposals for communication systems involving two home networks linked via virtual private network (VPN), that aim to use consumer electronics from the Internet. However, those systems have some problems. For example, against the user's wishes, the ITN connection makes all the contents available for other users as well. The user cannot access content because DLNA devices refuse access from outside the home network. In this paper, we propose a new system that expands the interconnection area from a home network to a mobile phone and consumer electronics in other home networks. Furthermore, we evaluate the proposed system by constructing a test bed that includes consumer electronics obtainable at stores.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127061779","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}
For the future we foresee each vehicle to feature wireless communication (to the Internet and/or other vehicles) over various technologies, e.g., UMTS/GPRS, and WLAN/WiFi. In this paper we show how access to such communication resources could be granted to individual components (CAN bus connected ECUs) in the car by allowing transparent data transport using the standardized Internet Protocol (IP). Our experiments show that a complete IP Over CAN implementation, providing both UDP and TCP transport over IP, running on an Atmel AT90CAN128 is capable of transfer speeds up to 200 kbits while using less than 2 kbytes of dynamic RAM.
在未来，我们预计每辆车都将通过各种技术(如UMTS/GPRS和WLAN/WiFi)实现无线通信(与互联网和/或其他车辆)。在本文中，我们展示了如何通过使用标准化互联网协议(IP)允许透明的数据传输，将此类通信资源的访问权限授予汽车中的各个组件(CAN总线连接的ecu)。我们的实验表明，一个完整的IP Over CAN实现，提供UDP和TCP的IP传输，在Atmel AT90CAN128上运行，能够在使用不到2 kb的动态RAM的情况下传输速度高达200 kb。
{"title":"IP over CAN, Transparent Vehicular to Infrastructure Access","authors":"P. Lindgren, Simon Aittamaa, Johan Eriksson","doi":"10.1109/CCNC08.2007.175","DOIUrl":"https://doi.org/10.1109/CCNC08.2007.175","url":null,"abstract":"For the future we foresee each vehicle to feature wireless communication (to the Internet and/or other vehicles) over various technologies, e.g., UMTS/GPRS, and WLAN/WiFi. In this paper we show how access to such communication resources could be granted to individual components (CAN bus connected ECUs) in the car by allowing transparent data transport using the standardized Internet Protocol (IP). Our experiments show that a complete IP Over CAN implementation, providing both UDP and TCP transport over IP, running on an Atmel AT90CAN128 is capable of transfer speeds up to 200 kbits while using less than 2 kbytes of dynamic RAM.","PeriodicalId":183858,"journal":{"name":"2008 5th IEEE Consumer Communications and Networking Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130711195","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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