Pub Date : 2003-03-23DOI: 10.1109/PERCOM.2003.1192740
Weichao Wang, Yi Lu, B. Bhargava
This paper compares the security properties of ad hoc on-demand distance vector (AODV) and destination sequence distance vector (DSDV) protocols, especially the difference caused by on-demand and proactive route queries. The on-demand route query enables the malicious host to conduct real time attacks on AODV. The communication overhead of attacks on DSDV is independent of the attack methods and the width of attack targets. A single false route propagates slower in AODV than in DSDV. The detection of false destination sequence in AODV heavily depends on the mobility of hosts. False distance vector and false destination sequence attacks are studied by simulation. The delivery ratio, communication overhead, and the propagation of false routes are measured by varying the traffic load and the maximum speed of host movement. The anomalous patterns of sequence numbers detected by destination hosts can be applied to detect the false destination sequence attacks.
{"title":"On security study of two distance vector routing protocols for mobile ad hoc networks","authors":"Weichao Wang, Yi Lu, B. Bhargava","doi":"10.1109/PERCOM.2003.1192740","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192740","url":null,"abstract":"This paper compares the security properties of ad hoc on-demand distance vector (AODV) and destination sequence distance vector (DSDV) protocols, especially the difference caused by on-demand and proactive route queries. The on-demand route query enables the malicious host to conduct real time attacks on AODV. The communication overhead of attacks on DSDV is independent of the attack methods and the width of attack targets. A single false route propagates slower in AODV than in DSDV. The detection of false destination sequence in AODV heavily depends on the mobility of hosts. False distance vector and false destination sequence attacks are studied by simulation. The delivery ratio, communication overhead, and the propagation of false routes are measured by varying the traffic load and the maximum speed of host movement. The anomalous patterns of sequence numbers detected by destination hosts can be applied to detect the false destination sequence attacks.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114563517","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192766
Sebastian Lühr, H. Bui, S. Venkatesh, G. West
Seeking to extend the functional capability of the elderly, we explore the use of probabilistic methods to learn and recognise human activity in order to provide monitoring support. We propose a novel approach to learning the hierarchical structure of sequences of human actions through the application of the hierarchical hidden Markov model (HHMM). Experimental results are presented for learning and recognising sequences of typical activities in a home.
{"title":"Recognition of human activity through hierarchical stochastic learning","authors":"Sebastian Lühr, H. Bui, S. Venkatesh, G. West","doi":"10.1109/PERCOM.2003.1192766","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192766","url":null,"abstract":"Seeking to extend the functional capability of the elderly, we explore the use of probabilistic methods to learn and recognise human activity in order to provide monitoring support. We propose a novel approach to learning the hierarchical structure of sequences of human actions through the application of the hierarchical hidden Markov model (HHMM). Experimental results are presented for learning and recognising sequences of typical activities in a home.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123987126","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192738
Jani Mäntyjärvi, J. Himberg, P. Huuskonen
Handheld communication devices equipped with sensing capabilities can recognize some aspects of their context to enable novel applications. We seek to improve the reliability of context recognition through an analogy to human behavior. Where multiple devices are around, they can jointly negotiate on a suitable context and behave accordingly. We have developed a method for this collaborative context recognition for handheld devices. The method determines the need to request and collaboratively recognize the current context of a group of handheld devices. It uses both local context time history information and spatial context information of handheld devices within a certain area. The method exploits dynamic weight parameters that describe content and reliability of context information. The performance of the method is analyzed using artificial and real context data. The results suggest that the method is capable of improving the reliability.
{"title":"Collaborative context recognition for handheld devices","authors":"Jani Mäntyjärvi, J. Himberg, P. Huuskonen","doi":"10.1109/PERCOM.2003.1192738","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192738","url":null,"abstract":"Handheld communication devices equipped with sensing capabilities can recognize some aspects of their context to enable novel applications. We seek to improve the reliability of context recognition through an analogy to human behavior. Where multiple devices are around, they can jointly negotiate on a suitable context and behave accordingly. We have developed a method for this collaborative context recognition for handheld devices. The method determines the need to request and collaboratively recognize the current context of a group of handheld devices. It uses both local context time history information and spatial context information of handheld devices within a certain area. The method exploits dynamic weight parameters that describe content and reliability of context information. The performance of the method is analyzed using artificial and real context data. The results suggest that the method is capable of improving the reliability.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125804456","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192754
S. B. Kodeswaran, Olga Ratsimor, A. Joshi, Timothy W. Finin, Y. Yesha
A mobile ad-hoc network is an autonomous system of mobile routers that are self-organizing and completely decentralized with no requirements for dedicated infrastructure support. Wireless infrastructure in terms of base stations is often available in many popular areas offering highspeed data connectivity to a wired network. In this paper we describe an approach where infrastructure components utilize passing by mobile nodes to route data to other devices that are out of range. In our scheme, base stations track user mobility and determine data usage patterns of users as they pass by. Based on this, base stations predict the future data needs for a passing mobile device. These base stations then collaborate (over the wired network) to identify other mobile devices with spare capacity whose routes intersect that of a needy device and use these carriers to transport the needed data. When such a carrier meets a needy device, they form ad hoc peer-to-peer communities to transfer this data. In this paper, we describe the motivation behind our approach and the different component interactions. We present the results of simulation work that we have done to validate the viability of our approach. We also describe, Numi, our framework for supporting collaborative infrastructure and ad hoc computing along with a sample application built on top of this highlighting the benefits of our proposed approach.
{"title":"Using peer-to-peer data routing for infrastructure-based wireless networks","authors":"S. B. Kodeswaran, Olga Ratsimor, A. Joshi, Timothy W. Finin, Y. Yesha","doi":"10.1109/PERCOM.2003.1192754","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192754","url":null,"abstract":"A mobile ad-hoc network is an autonomous system of mobile routers that are self-organizing and completely decentralized with no requirements for dedicated infrastructure support. Wireless infrastructure in terms of base stations is often available in many popular areas offering highspeed data connectivity to a wired network. In this paper we describe an approach where infrastructure components utilize passing by mobile nodes to route data to other devices that are out of range. In our scheme, base stations track user mobility and determine data usage patterns of users as they pass by. Based on this, base stations predict the future data needs for a passing mobile device. These base stations then collaborate (over the wired network) to identify other mobile devices with spare capacity whose routes intersect that of a needy device and use these carriers to transport the needed data. When such a carrier meets a needy device, they form ad hoc peer-to-peer communities to transfer this data. In this paper, we describe the motivation behind our approach and the different component interactions. We present the results of simulation work that we have done to validate the viability of our approach. We also describe, Numi, our framework for supporting collaborative infrastructure and ad hoc computing along with a sample application built on top of this highlighting the benefits of our proposed approach.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125819144","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 : 2003-03-23DOI: 10.1109/percom.2003.1192770
B. Sridharan, A. Mathur, K. Cai
A collection of one or more devices, each described by its digital device manual and reachable over a network, is a ConnectedSpace. A set of safety policies may be enforced on a ConnectedSpace to ensure the safety of the environment in which the ConnectedSpace is deployed. The enforcement of these safety policies by one or more safely controllers governs the behavior of the devices within the ConnectedSpace. We propose a policy-based partitioning scheme for synthesizing k distributed safety controllers such that: (a) each device is guaranteed to be controlled by no more than two controllers, and (b) each policy is guaranteed to be enforced by exactly one controller. We present an experimental evaluation of our scheme. The experimental results show that the scheme is scalable with respect to the number of devices and the number of policies. We also show how safety controllers that are correct with respect to the policies, are synthesized using the theory of supervisory control.
{"title":"Synthesizing distributed controllers for the safe operation of ConnectedSpaces","authors":"B. Sridharan, A. Mathur, K. Cai","doi":"10.1109/percom.2003.1192770","DOIUrl":"https://doi.org/10.1109/percom.2003.1192770","url":null,"abstract":"A collection of one or more devices, each described by its digital device manual and reachable over a network, is a ConnectedSpace. A set of safety policies may be enforced on a ConnectedSpace to ensure the safety of the environment in which the ConnectedSpace is deployed. The enforcement of these safety policies by one or more safely controllers governs the behavior of the devices within the ConnectedSpace. We propose a policy-based partitioning scheme for synthesizing k distributed safety controllers such that: (a) each device is guaranteed to be controlled by no more than two controllers, and (b) each policy is guaranteed to be enforced by exactly one controller. We present an experimental evaluation of our scheme. The experimental results show that the scheme is scalable with respect to the number of devices and the number of policies. We also show how safety controllers that are correct with respect to the policies, are synthesized using the theory of supervisory control.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131292753","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192782
S. Doumit, D. Agrawal
Today's wireless sensors act as information agents, our eyes and ears, for all types of applications, especially in inaccessible regions. But these sensors are resource-constrained devices; the key challenges remain in exploiting their limited time-life. A crucial factor to achieve this is to develop appropriate mobility models that would assure high information coverage of the desired deployed region within the area. We propose a biologically inspired mobility model to direct sensors' movement towards the target area. We show the benefits acquired in terms of data coverage and efficient resource-utilization.
{"title":"Bio-inspired mobility in environment aware wireless sensor networks","authors":"S. Doumit, D. Agrawal","doi":"10.1109/PERCOM.2003.1192782","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192782","url":null,"abstract":"Today's wireless sensors act as information agents, our eyes and ears, for all types of applications, especially in inaccessible regions. But these sensors are resource-constrained devices; the key challenges remain in exploiting their limited time-life. A crucial factor to achieve this is to develop appropriate mobility models that would assure high information coverage of the desired deployed region within the area. We propose a biologically inspired mobility model to direct sensors' movement towards the target area. We show the benefits acquired in terms of data coverage and efficient resource-utilization.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127794144","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192726
Mitali Singh, V. Prasanna
A large number of sensors networked together form selforganizing pervasive systems that provide the basis for implementation of several applications involving distributed, collaborative computations. Energy dissipation is a critical issue for these networks, as their life-time is limited by the battery power of the sensors. In this paper, we focus on design of an energy-balanced, energy-optimal algorithm for sorting in a single-hop sensor network. Energy optimality implies that the overall energy dissipation in the system is minimized. Energy-balancedness ensures that all the sensors spend asymptotically equivalent amount of energy in the system. Uniform energy dissipation is desirable as it enables the network to remain fully functional for the maximum time. We demonstrate that given a single-hop, singlechannel network of n randomly distributed sensors, sorting can be performed in O(n log n) time and energy, with no sensor being awake for more than O(log n) time steps. In a p-channel network, where p ∓ n1-ϵ for 0 < ϵ ∓ 1, sorting can be performed in O(n = p log n) time and O(n log n) energy with no node being awake for more than O(log n) time steps.
{"title":"Energy-optimal and energy-balanced sorting in a single-hop wireless sensor network","authors":"Mitali Singh, V. Prasanna","doi":"10.1109/PERCOM.2003.1192726","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192726","url":null,"abstract":"A large number of sensors networked together form selforganizing pervasive systems that provide the basis for implementation of several applications involving distributed, collaborative computations. Energy dissipation is a critical issue for these networks, as their life-time is limited by the battery power of the sensors. In this paper, we focus on design of an energy-balanced, energy-optimal algorithm for sorting in a single-hop sensor network. Energy optimality implies that the overall energy dissipation in the system is minimized. Energy-balancedness ensures that all the sensors spend asymptotically equivalent amount of energy in the system. Uniform energy dissipation is desirable as it enables the network to remain fully functional for the maximum time. We demonstrate that given a single-hop, singlechannel network of n randomly distributed sensors, sorting can be performed in O(n log n) time and energy, with no sensor being awake for more than O(log n) time steps. In a p-channel network, where p ∓ n1-ϵ for 0 < ϵ ∓ 1, sorting can be performed in O(n = p log n) time and O(n log n) energy with no node being awake for more than O(log n) time steps.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122406419","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192751
S. Ilarri, E. Mena, A. Illarramendi
Among mobile computing applications, location-based services are expected to be a big business for wireless operators. These services provide value added by considering the location of the user in order to give him/her more customized information. However, the processing of continuous location-dependent queries is still a subject of research. One of the key issues is how to update the answer presented to the user efficiently as it becomes obsolete very quickly. The goal of this paper is to analyze how to deal with situations where the answer cannot be updated with the desired frequency. We present several approaches to this problem and evaluate their performance.
{"title":"Dealing with continuous location-dependent queries: Just-in-time data refreshment","authors":"S. Ilarri, E. Mena, A. Illarramendi","doi":"10.1109/PERCOM.2003.1192751","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192751","url":null,"abstract":"Among mobile computing applications, location-based services are expected to be a big business for wireless operators. These services provide value added by considering the location of the user in order to give him/her more customized information. However, the processing of continuous location-dependent queries is still a subject of research. One of the key issues is how to update the answer presented to the user efficiently as it becomes obsolete very quickly. The goal of this paper is to analyze how to deal with situations where the answer cannot be updated with the desired frequency. We present several approaches to this problem and evaluate their performance.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129046064","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192735
Glenn Judd, P. Steenkiste
Pervasive computing applications are increasingly leveraging contextual information from several sources to provide users with behavior appropriate to the environment in which they reside. If these sources of contextual information are used and deployed in an ad hoc manner however they may provide overlapping functionality, fail to provide needed functionality, and require the use of inconsistent interfaces by applications. To overcome these problems, we introduce a contextual information service that provides applications with contextual information via a virtual database. Unlike previous efforts, our service provides applications a consistent, lightweight, and powerful mechanism for obtaining contextual information, and includes explicit support for the on demand computation of contextual information. We show, via example applications and a contextual information service prototype that we have implemented, how this approach can be used to allow proactive applications to adapt their behavior to match a user's current environment.
{"title":"Providing contextual information to pervasive computing applications","authors":"Glenn Judd, P. Steenkiste","doi":"10.1109/PERCOM.2003.1192735","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192735","url":null,"abstract":"Pervasive computing applications are increasingly leveraging contextual information from several sources to provide users with behavior appropriate to the environment in which they reside. If these sources of contextual information are used and deployed in an ad hoc manner however they may provide overlapping functionality, fail to provide needed functionality, and require the use of inconsistent interfaces by applications. To overcome these problems, we introduce a contextual information service that provides applications with contextual information via a virtual database. Unlike previous efforts, our service provides applications a consistent, lightweight, and powerful mechanism for obtaining contextual information, and includes explicit support for the on demand computation of contextual information. We show, via example applications and a contextual information service prototype that we have implemented, how this approach can be used to allow proactive applications to adapt their behavior to match a user's current environment.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116352064","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192745
A. C. Viana, M. Amorim, S. Fdida, J. Rezende
This paper proposes the Tribe protocol, an indirect routing strategy for wireless self-organizing networks. The protocol is intended to be applied in environments with large number of users, where mobility is taken into account, and the correct operation of the system does not require the support of a fixed (wired or wireless) infrastructure. In Tribe, nodes build a network infrastructure which describes the node's relative location according to the current node's neighborhood. Furthermore, routing is unique and completely independent of any global connectivity ensured by a network-level routing protocol. The architecture is generic, self-organizing, and independent of IP-like addressing limitations.
{"title":"Indirect routing using distributed location information","authors":"A. C. Viana, M. Amorim, S. Fdida, J. Rezende","doi":"10.1109/PERCOM.2003.1192745","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192745","url":null,"abstract":"This paper proposes the Tribe protocol, an indirect routing strategy for wireless self-organizing networks. The protocol is intended to be applied in environments with large number of users, where mobility is taken into account, and the correct operation of the system does not require the support of a fixed (wired or wireless) infrastructure. In Tribe, nodes build a network infrastructure which describes the node's relative location according to the current node's neighborhood. Furthermore, routing is unique and completely independent of any global connectivity ensured by a network-level routing protocol. The architecture is generic, self-organizing, and independent of IP-like addressing limitations.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126730371","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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