Pub Date : 2007-07-09DOI: 10.1109/COMSWA.2007.382478
D. Manjunath, S. Gopalaiah, Vijay Dewangan
Since their emergence, wireless sensor networks (WSNs) have become increasingly popular in the pervasive computing industry. This is particularly true within the past five years, which has seen sensor networks being adapted for wide variety of applications. Most of these applications are restricted to ambience monitoring and military use, however, very few commercial sensor applications have been explored till date. For WSNs to be truly ubiquitous, many more commercial sensor applications are yet to be investigated. As an effort to probe for such an application, we explore the potential of using WSNs in the field of Organizational Network Analysis (ONA). In this short paper, we propose a WSN based framework for analyzing organizational networks. We describe the role of WSNs in learning relationships among the people of an organization and investigate the research challenges involved in realizing the proposed framework.
{"title":"Wireless Sensor Networks for Organizational Network Analysis","authors":"D. Manjunath, S. Gopalaiah, Vijay Dewangan","doi":"10.1109/COMSWA.2007.382478","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382478","url":null,"abstract":"Since their emergence, wireless sensor networks (WSNs) have become increasingly popular in the pervasive computing industry. This is particularly true within the past five years, which has seen sensor networks being adapted for wide variety of applications. Most of these applications are restricted to ambience monitoring and military use, however, very few commercial sensor applications have been explored till date. For WSNs to be truly ubiquitous, many more commercial sensor applications are yet to be investigated. As an effort to probe for such an application, we explore the potential of using WSNs in the field of Organizational Network Analysis (ONA). In this short paper, we propose a WSN based framework for analyzing organizational networks. We describe the role of WSNs in learning relationships among the people of an organization and investigate the research challenges involved in realizing the proposed framework.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124951622","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382471
Wolfgang Schröder-Preikschat, R. Kapitza, J. Kleinöder, M. Felser, Katja Karmeier, T. H. Labella, F. Dressler
Software deployment and updating of deployed code is a critical topic in the area of wireless sensor networks (WSN). Reasons are unreliable network connectivity, resource limitations of devices, and energy restrictions in general. Consequently, software deployment has to be performed with great care otherwise resources might be wasted or nodes become unavailable due to failed updates. The overall objective for software management in sensor networks is to enable a robust and efficient way to build deployable software images that take into account all the needs from application requirements to node-specific resource restrictions. In this article, we outline the current state-of-the-art for software management in WSN and (network-based) sensor network (re-)programming. We provide insights into three different approaches enabling a more comprehensive management of WSN while challenging the robustness and efficiency of software configurations and reprogramming. Additionally, we outline research challenges in the area of software management and sensor network operation.
{"title":"Robust and Efficient Software Management in Sensor Networks","authors":"Wolfgang Schröder-Preikschat, R. Kapitza, J. Kleinöder, M. Felser, Katja Karmeier, T. H. Labella, F. Dressler","doi":"10.1109/COMSWA.2007.382471","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382471","url":null,"abstract":"Software deployment and updating of deployed code is a critical topic in the area of wireless sensor networks (WSN). Reasons are unreliable network connectivity, resource limitations of devices, and energy restrictions in general. Consequently, software deployment has to be performed with great care otherwise resources might be wasted or nodes become unavailable due to failed updates. The overall objective for software management in sensor networks is to enable a robust and efficient way to build deployable software images that take into account all the needs from application requirements to node-specific resource restrictions. In this article, we outline the current state-of-the-art for software management in WSN and (network-based) sensor network (re-)programming. We provide insights into three different approaches enabling a more comprehensive management of WSN while challenging the robustness and efficiency of software configurations and reprogramming. Additionally, we outline research challenges in the area of software management and sensor network operation.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131252109","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382593
K. Okayama, N. Yamai, Hayato Ishibashi, K. Abe, T. Matsuura
VPN (virtual private network) is one of the most important technologies on the Internet. With VPN, we can securely access to resources in the organizational network via the Internet. In VPNs having hierarchical structure, since each VPN domain has different access policy (whether VPN gateway should perform authentication, data encryption, and so on or not), an administrator of a VPN domain may need to configure access policies which are different from every VPN sub-domain. However, in the existing VPN methods, since access policies are stored in a static configuration file of each VPN gateway, an administrator of a VPN domain has to cooperate with the other administrators of its sub-domains. Therefore, management cost of access policies becomes considerably large if the organization has large and complicated structure. In this paper, we propose an efficient management method of access policies for hierarchical VPNs. In order to reduce management cost, we introduce a database with hierarchical structure to represent access policies easily and policy servers to get access policies automatically. The effectiveness of our proposed method is confirmed by an experiment on an actual network using policy servers based on the proposed method.
{"title":"An Efficient Management Method of Access Policies for Hierarchical Virtual Private Networks","authors":"K. Okayama, N. Yamai, Hayato Ishibashi, K. Abe, T. Matsuura","doi":"10.1109/COMSWA.2007.382593","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382593","url":null,"abstract":"VPN (virtual private network) is one of the most important technologies on the Internet. With VPN, we can securely access to resources in the organizational network via the Internet. In VPNs having hierarchical structure, since each VPN domain has different access policy (whether VPN gateway should perform authentication, data encryption, and so on or not), an administrator of a VPN domain may need to configure access policies which are different from every VPN sub-domain. However, in the existing VPN methods, since access policies are stored in a static configuration file of each VPN gateway, an administrator of a VPN domain has to cooperate with the other administrators of its sub-domains. Therefore, management cost of access policies becomes considerably large if the organization has large and complicated structure. In this paper, we propose an efficient management method of access policies for hierarchical VPNs. In order to reduce management cost, we introduce a database with hierarchical structure to represent access policies easily and policy servers to get access policies automatically. The effectiveness of our proposed method is confirmed by an experiment on an actual network using policy servers based on the proposed method.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114235824","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382555
B. K. Shrivastava, G. Khataniar, D. Goswami
Increased popularity of decentralized peer-to-peer (P2P) architecture comes with several challenges, like how to handle efficient lookup and query routing, frequent joining and leaving of nodes and scalability problem. Several key based deterministic routing approaches in a structured P2P networks have been proposed to overcome with these problems. Still, problems become worse if nodes are heterogenous in processing speed, power, stability and storage capability. To bridge the heterogeneity, we propose a 2-tier hierarchical distributed hash table (DHT) in which nodes are classified into three categories: temporary, stable and fully stable nodes. We have achieved intra-group lookup and query routing in O(log(|Gj|)) steps, where |Gj| is the number of (super)peers in destination group Gj, while inter-group lookup in O(1) steps. We have also saved at least 66.67% messages in repairing the routing table due to frequent joining and leaving of nodes in average case.
{"title":"Performance Enhancement in Hierarchical Peer-to-Peer Systems","authors":"B. K. Shrivastava, G. Khataniar, D. Goswami","doi":"10.1109/COMSWA.2007.382555","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382555","url":null,"abstract":"Increased popularity of decentralized peer-to-peer (P2P) architecture comes with several challenges, like how to handle efficient lookup and query routing, frequent joining and leaving of nodes and scalability problem. Several key based deterministic routing approaches in a structured P2P networks have been proposed to overcome with these problems. Still, problems become worse if nodes are heterogenous in processing speed, power, stability and storage capability. To bridge the heterogeneity, we propose a 2-tier hierarchical distributed hash table (DHT) in which nodes are classified into three categories: temporary, stable and fully stable nodes. We have achieved intra-group lookup and query routing in O(log(|Gj|)) steps, where |Gj| is the number of (super)peers in destination group Gj, while inter-group lookup in O(1) steps. We have also saved at least 66.67% messages in repairing the routing table due to frequent joining and leaving of nodes in average case.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114696178","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382426
V. Phoha, S. Phoha
Sensor networks represent a new frontier in technology that holds the promise of unprecedented levels of autonomy in the execution of complex dynamic missions by harnessing the power of many inexpensive electromechanical devices. A sensor network operates on an infrastructure for sensing, computation, and communication, through which it perceives the time evolution of physical dynamic processes in its operational environment. Hence the communications and computation software that enables the distributed time critical interactions of individual devices is characteristically different from traditional software. In particular, the operational environment for its execution is not predetermined and operational specifications are dynamic and therefore difficult to pin down. Hence existing programming methods like structured programming are not applicable. The ad hoc build, test, scrap approach will not work. This paper presents a deliberate high assurance design and debugging methodology, akin to the spiral model for software development, for building and validating dynamic, interoperable, programmable applications of sensor networks that involve management, information gathering, querying and tasking of the nodes for resource-constrained time-critical missions. A middleware architecture has been developed for sensor networks that extends agent communication languages for designing specific behaviors of sensor networks. Building on this architecture, we develop a high assurance software design coordination network for designing and validating dynamic agents that maintain desired behaviors of sensor network software despite faults, failures, uncertainties and environmental perturbations.
{"title":"Situation-Aware Software Engineering for Sensor Networks","authors":"V. Phoha, S. Phoha","doi":"10.1109/COMSWA.2007.382426","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382426","url":null,"abstract":"Sensor networks represent a new frontier in technology that holds the promise of unprecedented levels of autonomy in the execution of complex dynamic missions by harnessing the power of many inexpensive electromechanical devices. A sensor network operates on an infrastructure for sensing, computation, and communication, through which it perceives the time evolution of physical dynamic processes in its operational environment. Hence the communications and computation software that enables the distributed time critical interactions of individual devices is characteristically different from traditional software. In particular, the operational environment for its execution is not predetermined and operational specifications are dynamic and therefore difficult to pin down. Hence existing programming methods like structured programming are not applicable. The ad hoc build, test, scrap approach will not work. This paper presents a deliberate high assurance design and debugging methodology, akin to the spiral model for software development, for building and validating dynamic, interoperable, programmable applications of sensor networks that involve management, information gathering, querying and tasking of the nodes for resource-constrained time-critical missions. A middleware architecture has been developed for sensor networks that extends agent communication languages for designing specific behaviors of sensor networks. Building on this architecture, we develop a high assurance software design coordination network for designing and validating dynamic agents that maintain desired behaviors of sensor network software despite faults, failures, uncertainties and environmental perturbations.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121796723","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382413
Karsten Loesing, Maximilian Röglinger, Christian Wilms, G. Wirtz
Instant messaging (IM) systems provide its users with the information of which of their contacts are currently online. This presence information supplements text communication of IM systems and is an additional value compared to other synchronous communication media. Unauthorized users could illegally generate online logs of users by exploiting their presence information. Public IM systems lack the reliable means to protect user presence and force the user to trust in the central registry server. In this paper, we propose an IM system, which is explicitly designed to protect user presence without the need of a trusted central registry. We present a Java implementation based on the anonymous communication network Tor [1], the cryptographic suite Bouncy Castle [2], and the distributed hash table OpenDHT [3].
{"title":"Implementation of an Instant Messaging System with Focus on Protection of User Presence","authors":"Karsten Loesing, Maximilian Röglinger, Christian Wilms, G. Wirtz","doi":"10.1109/COMSWA.2007.382413","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382413","url":null,"abstract":"Instant messaging (IM) systems provide its users with the information of which of their contacts are currently online. This presence information supplements text communication of IM systems and is an additional value compared to other synchronous communication media. Unauthorized users could illegally generate online logs of users by exploiting their presence information. Public IM systems lack the reliable means to protect user presence and force the user to trust in the central registry server. In this paper, we propose an IM system, which is explicitly designed to protect user presence without the need of a trusted central registry. We present a Java implementation based on the anonymous communication network Tor [1], the cryptographic suite Bouncy Castle [2], and the distributed hash table OpenDHT [3].","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121050960","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382578
H. Reddy, M. Chandra, P. Balamuralidhar, G. HariharaS., Kaushik Bhattacharya, E. Joseph
Local positioning, particularly in indoor environments, poses challenges that are not faced by global and terrestrial positioning systems. Many a times, it is cost effective to build these localization schemes on the existing wireless local area networks (WLANs). This paper presents a novel time-of-arrival estimation technique for IEEE 802.11a WLAN system, which provides better accuracy than the traditional correlation-based scheme.
{"title":"An Improved Time-of-Arrival Estimation for WLAN-Based Local Positioning","authors":"H. Reddy, M. Chandra, P. Balamuralidhar, G. HariharaS., Kaushik Bhattacharya, E. Joseph","doi":"10.1109/COMSWA.2007.382578","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382578","url":null,"abstract":"Local positioning, particularly in indoor environments, poses challenges that are not faced by global and terrestrial positioning systems. Many a times, it is cost effective to build these localization schemes on the existing wireless local area networks (WLANs). This paper presents a novel time-of-arrival estimation technique for IEEE 802.11a WLAN system, which provides better accuracy than the traditional correlation-based scheme.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122794941","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382427
E. Fleury, Jean-Loup Guillaume, C. Robardet, A. Scherrer
Recent studies on wireless sensor networks (WSN) have shown that the duration of contacts and inter-contacts are power law distributed. While this is a strong property of these networks, we will show that this is not sufficient to describe properly the dynamics of sensor networks. We will present some coupled arguments from data mining, random processes and graph theory to describe more accurately the dynamics with the use of a random model to show the limits of an approach limited to power law contact durations.
{"title":"Analysis of Dynamic Sensor Networks: Power Law Then What?","authors":"E. Fleury, Jean-Loup Guillaume, C. Robardet, A. Scherrer","doi":"10.1109/COMSWA.2007.382427","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382427","url":null,"abstract":"Recent studies on wireless sensor networks (WSN) have shown that the duration of contacts and inter-contacts are power law distributed. While this is a strong property of these networks, we will show that this is not sufficient to describe properly the dynamics of sensor networks. We will present some coupled arguments from data mining, random processes and graph theory to describe more accurately the dynamics with the use of a random model to show the limits of an approach limited to power law contact durations.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115934962","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382615
Anubala S. Varikat
We consider a virtual multiple-input-multiple-output (MIMO) system, where mobile user equipments (UE) in the vicinity of each other act as antennas for each other for communication with a multiple-antenna base station (BS). The UEs communicate with each other on an 'Interlink', and with the BS on an Up/Downlink. A 'Sample-and-Forward' strategy is proposed for the downlink. The capacity of the proposed scheme and of a conventional Decode-and-Forward scheme for the uplink are investigated. Rules for optimal partitioning of time and bandwidth resources between the Interlink and the Up/Downlink are obtained. Capacity outage curves are provided to compare the virtual MIMO schemes with conventional MIMO and single-input-single-output (SISO) schemes.
{"title":"On the capacity of certain virtual MIMO schemes for mobie communications","authors":"Anubala S. Varikat","doi":"10.1109/COMSWA.2007.382615","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382615","url":null,"abstract":"We consider a virtual multiple-input-multiple-output (MIMO) system, where mobile user equipments (UE) in the vicinity of each other act as antennas for each other for communication with a multiple-antenna base station (BS). The UEs communicate with each other on an 'Interlink', and with the BS on an Up/Downlink. A 'Sample-and-Forward' strategy is proposed for the downlink. The capacity of the proposed scheme and of a conventional Decode-and-Forward scheme for the uplink are investigated. Rules for optimal partitioning of time and bandwidth resources between the Interlink and the Up/Downlink are obtained. Capacity outage curves are provided to compare the virtual MIMO schemes with conventional MIMO and single-input-single-output (SISO) schemes.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127072636","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 : 2007-07-09DOI: 10.1109/COMSWA.2007.382598
A. Prasad
This paper analyzes the security concerns of IEEE 802.11 WLAN based mesh networking for the home scenario. The paper also provides a novel solution to setup the wireless home area network (WHAN) with minimal user intervention. The proposed solution makes use of the concept of resurrecting duckling. Once the network is setup the proposed solution takes care that not only data but also management and control/signaling are secured. The paper also presents a security analysis of the novel solution.
{"title":"Securing Mesh Networks: A Novel Solution for Home Scenario","authors":"A. Prasad","doi":"10.1109/COMSWA.2007.382598","DOIUrl":"https://doi.org/10.1109/COMSWA.2007.382598","url":null,"abstract":"This paper analyzes the security concerns of IEEE 802.11 WLAN based mesh networking for the home scenario. The paper also provides a novel solution to setup the wireless home area network (WHAN) with minimal user intervention. The proposed solution makes use of the concept of resurrecting duckling. Once the network is setup the proposed solution takes care that not only data but also management and control/signaling are secured. The paper also presents a security analysis of the novel solution.","PeriodicalId":191295,"journal":{"name":"2007 2nd International Conference on Communication Systems Software and Middleware","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127195757","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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