Resource-constrained IoT sensors deployed over NDN have to carry scalable and thus long names within length-limited packets for global use, which produces additional overhead in fragmentation and network traffic across layers. However, for a local IoT region, sensors normally offer relatively mono-service of sensing therefore the same prefix of names in a periodical manner. Based on this observation, we introduce a Local Naming Service (LNS) to convert name between specific long name and symbolic short one for support of both valid global communication and lightweight local transmission. LNS explores the potential of name conversion on the fly while preserving data authentication in NDN packets.
{"title":"Local naming service for named data networking of things","authors":"Yating Yang, Tian Song","doi":"10.1145/3125719.3132104","DOIUrl":"https://doi.org/10.1145/3125719.3132104","url":null,"abstract":"Resource-constrained IoT sensors deployed over NDN have to carry scalable and thus long names within length-limited packets for global use, which produces additional overhead in fragmentation and network traffic across layers. However, for a local IoT region, sensors normally offer relatively mono-service of sensing therefore the same prefix of names in a periodical manner. Based on this observation, we introduce a Local Naming Service (LNS) to convert name between specific long name and symbolic short one for support of both valid global communication and lightweight local transmission. LNS explores the potential of name conversion on the fly while preserving data authentication in NDN packets.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117140446","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}
Onur Ascigil, Vasilis Sourlas, I. Psaras, G. Pavlou
Recent research has considered various approaches for discovering content in the cache-enabled nodes of an Autonomous System (AS) to reduce the costly inter-AS traffic. Such approaches include i) searching content opportunistically (on-path) along the default intra-AS path towards the content origin for limited gain, and ii) actively coordinate nodes when caching content for significantly higher gains, but also higher overhead. In this paper, we try to combine the merits of both worlds by using traditional opportunistic caching mechanisms enhanced with a lightweight content discovery approach. Particularly, a content retrieved through an inter-AS link is cached only once along the intra-AS delivery path to maximize network storage utilization, and ephemeral forwarding state to locate temporarily stored content is established opportunistically at each node along that path during the processing of Data packets. The ephemeral forwarding state either points to the arriving or the destination face of the Data packet depending on whether the content has already been cached along the path or not. The challenge in such an approach is to appropriately use and maintain the ephemeral forwarding state to minimize inter-AS content retrieval, while keeping retrieval latency and overhead at acceptable levels. We propose several forwarding strategies to use and manage ephemeral state and evaluate our mechanism using an ISP topology for various system parameters. Our results indicate that our opportunistic content discovery mechanism can achieve near-optimal performance and significantly reduce inter-AS traffic.
{"title":"A native content discovery mechanism for the information-centric networks","authors":"Onur Ascigil, Vasilis Sourlas, I. Psaras, G. Pavlou","doi":"10.1145/3125719.3125734","DOIUrl":"https://doi.org/10.1145/3125719.3125734","url":null,"abstract":"Recent research has considered various approaches for discovering content in the cache-enabled nodes of an Autonomous System (AS) to reduce the costly inter-AS traffic. Such approaches include i) searching content opportunistically (on-path) along the default intra-AS path towards the content origin for limited gain, and ii) actively coordinate nodes when caching content for significantly higher gains, but also higher overhead. In this paper, we try to combine the merits of both worlds by using traditional opportunistic caching mechanisms enhanced with a lightweight content discovery approach. Particularly, a content retrieved through an inter-AS link is cached only once along the intra-AS delivery path to maximize network storage utilization, and ephemeral forwarding state to locate temporarily stored content is established opportunistically at each node along that path during the processing of Data packets. The ephemeral forwarding state either points to the arriving or the destination face of the Data packet depending on whether the content has already been cached along the path or not. The challenge in such an approach is to appropriately use and maintain the ephemeral forwarding state to minimize inter-AS content retrieval, while keeping retrieval latency and overhead at acceptable levels. We propose several forwarding strategies to use and manage ephemeral state and evaluate our mechanism using an ISP topology for various system parameters. Our results indicate that our opportunistic content discovery mechanism can achieve near-optimal performance and significantly reduce inter-AS traffic.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123514763","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}
Alberto Compagno, Xuan Zeng, L. Muscariello, G. Carofiglio, J. Augé
One of the fundamental requirements of the next generation 5G networks is to support seamless mobility over an heterogeneous access network by design. The shift from host-based to content-based location-independent communication makes Information-Centric Networking (ICN) an appealing technology to provide not only mobility, but also security and storage as native properties of the network architecture. Previous work in ICN literature focused on name-based mobility management solutions and particularly on the challenges of producer mobility, which involves an interaction between forwarding and control plane. In this paper, we consider the security implications of producer mobility in ICN and we highlight the importance of securing producer to network interactions. We focus on the problem of prefix hijacking: a class of attacks that can be exploited to threaten both the security of the ICN networks and the privacy of its users. To prevent this class of attacks, we propose a fully distributed and very low-overhead protocol for name prefix attestation based on hash-chaining. First results show order of magnitudes improvement in verification latency with respect to signature verification, the leading alternative approach to thwart prefix hijacking attacks.
{"title":"Secure producer mobility in information-centric network","authors":"Alberto Compagno, Xuan Zeng, L. Muscariello, G. Carofiglio, J. Augé","doi":"10.1145/3125719.3125725","DOIUrl":"https://doi.org/10.1145/3125719.3125725","url":null,"abstract":"One of the fundamental requirements of the next generation 5G networks is to support seamless mobility over an heterogeneous access network by design. The shift from host-based to content-based location-independent communication makes Information-Centric Networking (ICN) an appealing technology to provide not only mobility, but also security and storage as native properties of the network architecture. Previous work in ICN literature focused on name-based mobility management solutions and particularly on the challenges of producer mobility, which involves an interaction between forwarding and control plane. In this paper, we consider the security implications of producer mobility in ICN and we highlight the importance of securing producer to network interactions. We focus on the problem of prefix hijacking: a class of attacks that can be exploited to threaten both the security of the ICN networks and the privacy of its users. To prevent this class of attacks, we propose a fully distributed and very low-overhead protocol for name prefix attestation based on hash-chaining. First results show order of magnitudes improvement in verification latency with respect to signature verification, the leading alternative approach to thwart prefix hijacking attacks.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"166 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126747579","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}
Niels L. M. van Adrichem, Bastiaan Wissingh, D. Ravesteijn, L. D'Acunto
The end-to-end connection paradigm of TCP/IP does not work well in situations characterized by intermittent (or no) global internet connectivity, as often is the case in offshore Wireless Sensor Networks (WSNs), military networks, rural/remote areas and maritime transport. Delay/Disruption Tolerant Networking (DTN) investigates to address these use cases, often built as an overlay on top of existing network infrastructure. ICN is a new internet architecture aiming to replace TCP/IP, whose data-oriented paradigm seems a very good match with the requirements of applications where connectivity is intermittent or absent. Hence, potentially eliminating additional DTN overlays. In this demo, we will showcase how ICN can be used for data muling between two disconnected "islands". New data will be generated in real-time on each island, and participants will be given the possibility of muling interactively generated data between the islands via mobile phones and small single-board computers.
{"title":"Data muling in ICN","authors":"Niels L. M. van Adrichem, Bastiaan Wissingh, D. Ravesteijn, L. D'Acunto","doi":"10.1145/3125719.3132094","DOIUrl":"https://doi.org/10.1145/3125719.3132094","url":null,"abstract":"The end-to-end connection paradigm of TCP/IP does not work well in situations characterized by intermittent (or no) global internet connectivity, as often is the case in offshore Wireless Sensor Networks (WSNs), military networks, rural/remote areas and maritime transport. Delay/Disruption Tolerant Networking (DTN) investigates to address these use cases, often built as an overlay on top of existing network infrastructure. ICN is a new internet architecture aiming to replace TCP/IP, whose data-oriented paradigm seems a very good match with the requirements of applications where connectivity is intermittent or absent. Hence, potentially eliminating additional DTN overlays. In this demo, we will showcase how ICN can be used for data muling between two disconnected \"islands\". New data will be generated in real-time on each island, and participants will be given the possibility of muling interactively generated data between the islands via mobile phones and small single-board computers.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116883258","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 use of Named Data Networking (NDN) for distributed multi-user applications, e.g. group messaging and file sharing, requires NDN synchronization protocols to maintain the same shared dataset (and its updates) among all nodes. ChronoSync [1], RoundSync [2], and PartialSync [3] are some proposals to address this issue, see [4]. Here we focus on the state-of-the-art protocol RoundSync [2]: we study its core features, that permit participating nodes to detect, propagate, and reconcile all changes. Particular attention is given to the case of multiple changes per round. We then propose an improved variant, iRoundSync, that exchanges fewer messages in the multiple-change case and is more resilient to packet losses. We quantify the performance gain of iRoundSync on a simple topology.
{"title":"NDN synchronization: iRoundSync, an improved RoundSync","authors":"A. Hindi, M. Kieffer, C. Adjih, C. Weidmann","doi":"10.1145/3125719.3132108","DOIUrl":"https://doi.org/10.1145/3125719.3132108","url":null,"abstract":"The use of Named Data Networking (NDN) for distributed multi-user applications, e.g. group messaging and file sharing, requires NDN synchronization protocols to maintain the same shared dataset (and its updates) among all nodes. ChronoSync [1], RoundSync [2], and PartialSync [3] are some proposals to address this issue, see [4]. Here we focus on the state-of-the-art protocol RoundSync [2]: we study its core features, that permit participating nodes to detect, propagate, and reconcile all changes. Particular attention is given to the case of multiple changes per round. We then propose an improved variant, iRoundSync, that exchanges fewer messages in the multiple-change case and is more resilient to packet losses. We quantify the performance gain of iRoundSync on a simple topology.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128790587","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}
Onur Ascigil, Sergi Rene, G. Xylomenos, I. Psaras, G. Pavlou
Information-Centric Networking (ICN) has been proposed as a promising solution for the Internet of Things (IoT), due to its focus on naming data, rather than endpoints, which can greatly simplify applications. The hierarchical naming of the Named-Data Networking (NDN) architecture can be used to name groups of data values, for example, all temperature sensors in a building. However, the use of a single naming hierarchy for all kinds of different applications is inflexible. Moreover, IoT data are typically retrieved from multiple sources at the same time, allowing applications to aggregate similar information items, something not natively supported by NDN. To this end, in this paper we propose (a) locating IoT data using (unordered) keywords combined with NDN names and (b) processing multiple such items at the edge of the network with arbitrary functions. We describe and evaluate three different strategies for retrieving data and placing the calculations in the edge IoT network, thus combining connectivity, storage and computing.
{"title":"A keyword-based ICN-IoT platform","authors":"Onur Ascigil, Sergi Rene, G. Xylomenos, I. Psaras, G. Pavlou","doi":"10.1145/3125719.3125733","DOIUrl":"https://doi.org/10.1145/3125719.3125733","url":null,"abstract":"Information-Centric Networking (ICN) has been proposed as a promising solution for the Internet of Things (IoT), due to its focus on naming data, rather than endpoints, which can greatly simplify applications. The hierarchical naming of the Named-Data Networking (NDN) architecture can be used to name groups of data values, for example, all temperature sensors in a building. However, the use of a single naming hierarchy for all kinds of different applications is inflexible. Moreover, IoT data are typically retrieved from multiple sources at the same time, allowing applications to aggregate similar information items, something not natively supported by NDN. To this end, in this paper we propose (a) locating IoT data using (unordered) keywords combined with NDN names and (b) processing multiple such items at the edge of the network with arbitrary functions. We describe and evaluate three different strategies for retrieving data and placing the calculations in the edge IoT network, thus combining connectivity, storage and computing.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128128304","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}
Named Data Networks (NDN) is an emerging data centric networking paradigm that provides an efficient and resilient communication model. To facilitate experimentation and integration of NDN, we introduce a general purpose/extensible IP-to-NDN gateway. The gateway enables applications modeled after the IP client-server model to operate seamlessly through an NDN cloud. These applications can then gain the benefits of NDN without having to be recoded or redesigned. We focus our demonstration on applications operating in challenged network environments (e.g. military tactical networks). We integrate Cursor-on-Target (CoT) [1], a message router used for situational awareness, as well as XMPP Overlay (XOP) [3], a decentralized chat application, into an NDN cloud. We show the ease of integration and the benefits these applications gain from NDN under severely disrupted network conditions.
{"title":"Integrating IP and NDN through an extensible IP-NDN gateway","authors":"M. Refaei, Jamie Ma, Sean Ha, Sarah Liu","doi":"10.1145/3125719.3132112","DOIUrl":"https://doi.org/10.1145/3125719.3132112","url":null,"abstract":"Named Data Networks (NDN) is an emerging data centric networking paradigm that provides an efficient and resilient communication model. To facilitate experimentation and integration of NDN, we introduce a general purpose/extensible IP-to-NDN gateway. The gateway enables applications modeled after the IP client-server model to operate seamlessly through an NDN cloud. These applications can then gain the benefits of NDN without having to be recoded or redesigned. We focus our demonstration on applications operating in challenged network environments (e.g. military tactical networks). We integrate Cursor-on-Target (CoT) [1], a message router used for situational awareness, as well as XMPP Overlay (XOP) [3], a decentralized chat application, into an NDN cloud. We show the ease of integration and the benefits these applications gain from NDN under severely disrupted network conditions.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133471730","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}
Scientific domains such as Climate Science, High Energy Particle Physics (HEP) and others, routinely generate and manage petabytes of data, projected to rise into exabytes [26]. The sheer volume and long life of the data stress IP networking and traditional content distribution networks mechanisms. Thus, each scientific domain typically designs, develops, implements, deploys and maintains its own data management and distribution system, often duplicating functionality. Supporting various incarnations of similar software is wasteful, prone to bugs, and results in an ecosystem of one-off solutions. In this paper, we present the first trace-driven study that investigates NDN in the context of a scientific application domain. Our contribution is threefold. First, we analyze a three-year climate data server log and characterize data access patterns to expose important variables such as cache size. Second, using an approximated topology derived from the log, we replay log requests in real-time over an NDN simulator to evaluate how NDN improves traffic flows through aggregation and caching. Finally, we implement a simple, nearest-replica NDN forwarding strategy and evaluate how NDN can improve scientific content delivery.
{"title":"Request aggregation, caching, and forwarding strategies for improving large climate data distribution with NDN: a case study","authors":"Susmit Shannigrahi, Chengyu Fan, C. Papadopoulos","doi":"10.1145/3125719.3125722","DOIUrl":"https://doi.org/10.1145/3125719.3125722","url":null,"abstract":"Scientific domains such as Climate Science, High Energy Particle Physics (HEP) and others, routinely generate and manage petabytes of data, projected to rise into exabytes [26]. The sheer volume and long life of the data stress IP networking and traditional content distribution networks mechanisms. Thus, each scientific domain typically designs, develops, implements, deploys and maintains its own data management and distribution system, often duplicating functionality. Supporting various incarnations of similar software is wasteful, prone to bugs, and results in an ecosystem of one-off solutions. In this paper, we present the first trace-driven study that investigates NDN in the context of a scientific application domain. Our contribution is threefold. First, we analyze a three-year climate data server log and characterize data access patterns to expose important variables such as cache size. Second, using an approximated topology derived from the log, we replay log requests in real-time over an NDN simulator to evaluate how NDN improves traffic flows through aggregation and caching. Finally, we implement a simple, nearest-replica NDN forwarding strategy and evaluate how NDN can improve scientific content delivery.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126125111","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}
Kazuaki Ueda, Yuma Ishigaki, A. Tagami, T. Hasegawa
This demonstration shows an efficient panoramic streaming application with ICN functionalities. The camera device splits its field-of-view into multiple named tiles, and clients request minimum tiles for their field-of-view. These named tiles are cached at the intermediate routers and the camera device can reduce the amount of traffic on its access network. By utilizing the ICN's merits, this application can work with limited resources, like IoT environment.
{"title":"Demo: panoramic streaming using named tiles","authors":"Kazuaki Ueda, Yuma Ishigaki, A. Tagami, T. Hasegawa","doi":"10.1145/3125719.3132093","DOIUrl":"https://doi.org/10.1145/3125719.3132093","url":null,"abstract":"This demonstration shows an efficient panoramic streaming application with ICN functionalities. The camera device splits its field-of-view into multiple named tiles, and clients request minimum tiles for their field-of-view. These named tiles are cached at the intermediate routers and the camera device can reduce the amount of traffic on its access network. By utilizing the ICN's merits, this application can work with limited resources, like IoT environment.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124389625","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}
Persistent Interests (PIs) are a promising approach to introduce push-type traffic in Named Data Networking (NDN), in particular for conversational services such as voice and video calls. Forwarding decisions for PIs are crucial in NDN because they establish a long-lived path for the data flowing back toward the PI issuer. In the course of studying the use of PIs in NDN, we investigate adaptive PI forwarding and present a strategy combining regular NDN forwarding information and results from probing potential alternative paths through the network. Simulation results indicate that our adaptive PI forwarding approach is superior to the PI-adapted Best Route strategy when network conditions change due to link failures.
{"title":"Adaptive forwarding of persistent interests in named data networking","authors":"Philipp Moll, Julian Janda, H. Hellwagner","doi":"10.1145/3125719.3132091","DOIUrl":"https://doi.org/10.1145/3125719.3132091","url":null,"abstract":"Persistent Interests (PIs) are a promising approach to introduce push-type traffic in Named Data Networking (NDN), in particular for conversational services such as voice and video calls. Forwarding decisions for PIs are crucial in NDN because they establish a long-lived path for the data flowing back toward the PI issuer. In the course of studying the use of PIs in NDN, we investigate adaptive PI forwarding and present a strategy combining regular NDN forwarding information and results from probing potential alternative paths through the network. Simulation results indicate that our adaptive PI forwarding approach is superior to the PI-adapted Best Route strategy when network conditions change due to link failures.","PeriodicalId":394653,"journal":{"name":"Proceedings of the 4th ACM Conference on Information-Centric Networking","volume":"182 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116898268","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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