Pub Date : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844095
Kita Nozomi, Fujun He, E. Oki
Middleboxes work as software which runs on a general-purpose server by adopting a network function virtualization. The unavailability of middlebox is a key metric. The previous study considers allocating backup servers to middleboxes to reduce the unavailability. While it adopts shared protection to save backup capacity, resource sharing has not been sufficiently explored as each middlebox can only use one backup server. This paper presents a backup allocation model in which a function can be protected by two backup servers and a backup server can protect multiple functions under a shared protection strategy to minimize the maximum unavailability among functions. We use Markov chains to analyze the state transitions and make equilibrium-state equations. By solving them, we obtain the probability of each state of the allocation and compute an unavailability of function. We introduce two algorithms to examine the proposed model; one of them uses the performance bound of the maximum unavailability which is analyzed in this paper. Numerical results show that the proposed model reduces the maximum unavailability by 13.9-51.2% compared to a baseline model that allocates one backup server for each middlebox in our examined cases.
{"title":"Unavailability-Aware Backup Allocation Model for Middleboxes with Two-Stage Shared Protection","authors":"Kita Nozomi, Fujun He, E. Oki","doi":"10.1109/NetSoft54395.2022.9844095","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844095","url":null,"abstract":"Middleboxes work as software which runs on a general-purpose server by adopting a network function virtualization. The unavailability of middlebox is a key metric. The previous study considers allocating backup servers to middleboxes to reduce the unavailability. While it adopts shared protection to save backup capacity, resource sharing has not been sufficiently explored as each middlebox can only use one backup server. This paper presents a backup allocation model in which a function can be protected by two backup servers and a backup server can protect multiple functions under a shared protection strategy to minimize the maximum unavailability among functions. We use Markov chains to analyze the state transitions and make equilibrium-state equations. By solving them, we obtain the probability of each state of the allocation and compute an unavailability of function. We introduce two algorithms to examine the proposed model; one of them uses the performance bound of the maximum unavailability which is analyzed in this paper. Numerical results show that the proposed model reduces the maximum unavailability by 13.9-51.2% compared to a baseline model that allocates one backup server for each middlebox in our examined cases.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123608247","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844075
Fetia Bannour, Stefania Dumbrava, Alex Danduran-Lembezat
The Software-Defined Networking (SDN) paradigm relies on decoupling the control and data planes, and logically centralizing SDN control to enable direct network programming via open interfaces. New abstractions are thus needed in a bid to rethink the traditional networking approach and create new opportunities for management and automation. We demonstrate the GOX controller, proposing a novel graph abstraction of the network topology in real time using the scalable Neo4j graph database. Our proof-of-concept was evaluated for a forwarding application designed for GOX. Compared to POX’s model, GOX shows better performance and scalability on synthetic topologies and real-world topologies from the Internet Topology Zoo.
{"title":"GOX: Towards a Scalable Graph Database-Driven SDN Controller","authors":"Fetia Bannour, Stefania Dumbrava, Alex Danduran-Lembezat","doi":"10.1109/NetSoft54395.2022.9844075","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844075","url":null,"abstract":"The Software-Defined Networking (SDN) paradigm relies on decoupling the control and data planes, and logically centralizing SDN control to enable direct network programming via open interfaces. New abstractions are thus needed in a bid to rethink the traditional networking approach and create new opportunities for management and automation. We demonstrate the GOX controller, proposing a novel graph abstraction of the network topology in real time using the scalable Neo4j graph database. Our proof-of-concept was evaluated for a forwarding application designed for GOX. Compared to POX’s model, GOX shows better performance and scalability on synthetic topologies and real-world topologies from the Internet Topology Zoo.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126284921","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844037
Rafael Direito, D. Gomes, Rui L. Aguiar
5G technologies provide several advancements regarding low latency and high bandwidth network scenarios, thus enabling new vertical use cases. Nonetheless, the lack of testing and validation mechanisms for NFV-based services poses a severe challenge in reducing their time to market. In this work we showcase a service to automate the validation of 5G NetApps, thus striving towards reducing the time to market of these applications, and introducing a new layer of trust in their reliability and availability.
{"title":"Towards a Fully Automated System for Testing and Validating NetApps","authors":"Rafael Direito, D. Gomes, Rui L. Aguiar","doi":"10.1109/NetSoft54395.2022.9844037","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844037","url":null,"abstract":"5G technologies provide several advancements regarding low latency and high bandwidth network scenarios, thus enabling new vertical use cases. Nonetheless, the lack of testing and validation mechanisms for NFV-based services poses a severe challenge in reducing their time to market. In this work we showcase a service to automate the validation of 5G NetApps, thus striving towards reducing the time to market of these applications, and introducing a new layer of trust in their reliability and availability.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127749180","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844023
R. D. Corin, Silvio Cretti, T. Catena, Simone Magnani, D. Siracusa
In network security, Network Function Virtualization can be exploited to implement flexible security services tailored to specific user needs. However, in practice this is hard to achieve due to the limitations of reference software platforms, such as Kubernetes, which are designed to orchestrate cloud-native services. In this work, we complement Kubernetes with a state-of-the-art algorithm for application-aware provisioning of security services. We demonstrate that the proposed solution improves basic provisioning mechanisms, such as the default Kubernetes scheduler, in terms of Quality of Service and security guarantees for the users.
{"title":"Towards Application-Aware Provisioning of Security Services with Kubernetes","authors":"R. D. Corin, Silvio Cretti, T. Catena, Simone Magnani, D. Siracusa","doi":"10.1109/NetSoft54395.2022.9844023","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844023","url":null,"abstract":"In network security, Network Function Virtualization can be exploited to implement flexible security services tailored to specific user needs. However, in practice this is hard to achieve due to the limitations of reference software platforms, such as Kubernetes, which are designed to orchestrate cloud-native services. In this work, we complement Kubernetes with a state-of-the-art algorithm for application-aware provisioning of security services. We demonstrate that the proposed solution improves basic provisioning mechanisms, such as the default Kubernetes scheduler, in terms of Quality of Service and security guarantees for the users.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128193380","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844063
George Papathanail, Ioannis Dimolitsas, Ioakeim Fotoglou, Dimitrios Dechouniotis, S. Papavassiliou, Panagiotis Papadimitriou
Network slicing has been at the forefront of 5G network research, with various slicing orchestration architectures seeking to reap the benefits of slicing for the enhanced performance and reliability of 5G (and beyond) network services. In this context, cross-slice communication (CSC) has drawn significant attention, since CSC can foster interactions among services deployed in co-located slices, lowering the barrier for the consumption of services.To capitalize the benefits of CSC (e.g., reduced latency and cost), CSC should be established with the highest degree of co-location and also in a secure and policy-compliant manner. To this end, we present an orchestration framework that fulfills all main technical requirements for CSC instantiation. In this respect, we elaborate on the CSC instantiation workflows and shed light into the cross-layer interactions that span our proposed CSC orchestrator, the Network Function Virtualization Orchestrator (NFVO) and the Virtualized Infrastructure Manager (VIM). Our experimental results indicate that our proposed CSC orchestration framework introduces a negligible performance overhead and also incurs a minimal latency inflation compared to a direct form of inter-slice communication without any provision for security and resource isolation.
{"title":"Towards Secure and Optimized Cross-Slice Communication Establishment","authors":"George Papathanail, Ioannis Dimolitsas, Ioakeim Fotoglou, Dimitrios Dechouniotis, S. Papavassiliou, Panagiotis Papadimitriou","doi":"10.1109/NetSoft54395.2022.9844063","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844063","url":null,"abstract":"Network slicing has been at the forefront of 5G network research, with various slicing orchestration architectures seeking to reap the benefits of slicing for the enhanced performance and reliability of 5G (and beyond) network services. In this context, cross-slice communication (CSC) has drawn significant attention, since CSC can foster interactions among services deployed in co-located slices, lowering the barrier for the consumption of services.To capitalize the benefits of CSC (e.g., reduced latency and cost), CSC should be established with the highest degree of co-location and also in a secure and policy-compliant manner. To this end, we present an orchestration framework that fulfills all main technical requirements for CSC instantiation. In this respect, we elaborate on the CSC instantiation workflows and shed light into the cross-layer interactions that span our proposed CSC orchestrator, the Network Function Virtualization Orchestrator (NFVO) and the Virtualized Infrastructure Manager (VIM). Our experimental results indicate that our proposed CSC orchestration framework introduces a negligible performance overhead and also incurs a minimal latency inflation compared to a direct form of inter-slice communication without any provision for security and resource isolation.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129979828","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844093
D. Harris, D. Raz
The ongoing transition into 5G networks is enabled in part by the combination of NFV (Network Function Virtualization) and MEC (Multi-access Edge Computing), two promising paradigms that allow executing ultra-low-latency network services on edge nodes, physically closer to the clients. However, orchestrating this complex distributed environment and especially provisioning services in a timely manner, in order to address the dynamic workload, remained a big challenge. In this paper we address this challenge and study ways to dynamically place network functions at edge nodes, across the network, in a way that maximizes client satisfaction, we measure this satisfaction by the number of clients that received their desired services in a manner that holds these required services low-latency demands. In order to balance between the dynamic workload and the non-negligible cost of replacing the functions at the edge, we partition the time into epochs and reassign VNFs (Virtual Network Functions) only at the beginning of each epoch. Our theoretical analysis, based on studying a simple variant of the online problem, shows that the data from the last epoch can provide guarantees on the expected performance. We then evaluate the actual performance of our algorithm based on extensive simulations over real data. The results indicate that our new algorithm can be deployed in a realistic 5G setting, generating an overall dynamic solution that outperforms currently used methods.
{"title":"Dynamic VNF Placement in 5G Edge Nodes","authors":"D. Harris, D. Raz","doi":"10.1109/NetSoft54395.2022.9844093","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844093","url":null,"abstract":"The ongoing transition into 5G networks is enabled in part by the combination of NFV (Network Function Virtualization) and MEC (Multi-access Edge Computing), two promising paradigms that allow executing ultra-low-latency network services on edge nodes, physically closer to the clients. However, orchestrating this complex distributed environment and especially provisioning services in a timely manner, in order to address the dynamic workload, remained a big challenge. In this paper we address this challenge and study ways to dynamically place network functions at edge nodes, across the network, in a way that maximizes client satisfaction, we measure this satisfaction by the number of clients that received their desired services in a manner that holds these required services low-latency demands. In order to balance between the dynamic workload and the non-negligible cost of replacing the functions at the edge, we partition the time into epochs and reassign VNFs (Virtual Network Functions) only at the beginning of each epoch. Our theoretical analysis, based on studying a simple variant of the online problem, shows that the data from the last epoch can provide guarantees on the expected performance. We then evaluate the actual performance of our algorithm based on extensive simulations over real data. The results indicate that our new algorithm can be deployed in a realistic 5G setting, generating an overall dynamic solution that outperforms currently used methods.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134172917","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844020
A. Clemm, C. Westphal
Reducing mankind’s carbon footprint and becoming more sustainable is rapidly becoming one of the main challenges of our age. The networking industry needs to respond to those challenges not only by enabling applications that allow users to save energy (such as, replacing travel with teleconferencing), but also by making networking technology itself significantly more energy-efficient. As a result, the aspect of minimizing network power consumption is rapidly increasing in importance. This position paper aims to articulate opportunities where energy efficiency of networks can be improved, to point out the associated technical challenges, and to identify corresponding research challenges.
{"title":"Challenges and Opportunities in Green Networking","authors":"A. Clemm, C. Westphal","doi":"10.1109/NetSoft54395.2022.9844020","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844020","url":null,"abstract":"Reducing mankind’s carbon footprint and becoming more sustainable is rapidly becoming one of the main challenges of our age. The networking industry needs to respond to those challenges not only by enabling applications that allow users to save energy (such as, replacing travel with teleconferencing), but also by making networking technology itself significantly more energy-efficient. As a result, the aspect of minimizing network power consumption is rapidly increasing in importance. This position paper aims to articulate opportunities where energy efficiency of networks can be improved, to point out the associated technical challenges, and to identify corresponding research challenges.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134530461","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844035
Antonino Angi, Alessio Sacco, Flavio Esposito, G. Marchetto, A. Clemm
Translating high-level policies to lower-level network rules is one of the main goals of control or data plane network programmability. To further abstract requirements and propel automation in networking, several industries have proposed the paradigm of “network intent”. However, the translation from intents to low-level policies is considered critical to program data planes and other network elements, especially when dealing with P4-enabled switches. In this paper, we present NLP4, an architecture that helps translate intents, in the form of human language, into data-plane programs, in the form of P4 rules. In particular, NLP4 uses Natural Language Processing (NLP) techniques to translate high-level human-language intents, a MultiLayer Perceptron (MLP) model for processing the NLP output and converting it into mid-level policy. An API then uses this information, which separates the intent from the network to generate commands readable by P4-enabled switches. Our initial prototype on a network emulator validates our architecture for a specific case: load profiling, demonstrating how even users with limited P4 expertise may customize their networks by merely specifying intents.
{"title":"NLP4: An Architecture for Intent-Driven Data Plane Programmability","authors":"Antonino Angi, Alessio Sacco, Flavio Esposito, G. Marchetto, A. Clemm","doi":"10.1109/NetSoft54395.2022.9844035","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844035","url":null,"abstract":"Translating high-level policies to lower-level network rules is one of the main goals of control or data plane network programmability. To further abstract requirements and propel automation in networking, several industries have proposed the paradigm of “network intent”. However, the translation from intents to low-level policies is considered critical to program data planes and other network elements, especially when dealing with P4-enabled switches. In this paper, we present NLP4, an architecture that helps translate intents, in the form of human language, into data-plane programs, in the form of P4 rules. In particular, NLP4 uses Natural Language Processing (NLP) techniques to translate high-level human-language intents, a MultiLayer Perceptron (MLP) model for processing the NLP output and converting it into mid-level policy. An API then uses this information, which separates the intent from the network to generate commands readable by P4-enabled switches. Our initial prototype on a network emulator validates our architecture for a specific case: load profiling, demonstrating how even users with limited P4 expertise may customize their networks by merely specifying intents.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114285173","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 : 2022-06-27DOI: 10.1109/NetSoft54395.2022.9844124
Elia Battiston, Daniele Moro, G. Verticale, A. Capone
Network Function Virtualization has dramatically increased the flexibility in the deployment of network services, however the execution of virtual functions on compute nodes equipped with general purpose hardware can result in worse performance compared to the middleboxes they aim to replace. The use of programmable network hardware to perform part of the processing at line rate can drastically increase the throughput while retaining the flexibility.This work presents a new framework, called CHIMA, which extends the capabilities of other frameworks proposed in the literature for the deployment of heterogeneous Service Function Chains (SFCs). Heterogeneous SFCs comprise a combination of virtual functions meant to be executed in containers running on general purpose hardware and of functions for programmable switches written using the P4 language. CHIMA exploits programmable data planes to perform real time monitoring of the services through In-band Network Telemetry and uses the collected information to guarantee the requested levels of performance by redeploying and rerouting sections that are affected by adverse conditions, allowing applications with critical requirements to be deployed as SFCs.The solution has been tested by emulating various topologies and services on the FOP4 platform with bmv2 switches. The analysis shows that the system is capable of detecting faults in the order of hundreds of milliseconds, and the overhead it causes in the process of redeployment is negligible compared to the startup time of functions. Measurements also reveal that the current bottleneck for the runtime relocation of heterogeneous functions is the redeployment and reconfiguration of P4 programs.
{"title":"CHIMA: a Framework for Network Services Deployment and Performance Assurance","authors":"Elia Battiston, Daniele Moro, G. Verticale, A. Capone","doi":"10.1109/NetSoft54395.2022.9844124","DOIUrl":"https://doi.org/10.1109/NetSoft54395.2022.9844124","url":null,"abstract":"Network Function Virtualization has dramatically increased the flexibility in the deployment of network services, however the execution of virtual functions on compute nodes equipped with general purpose hardware can result in worse performance compared to the middleboxes they aim to replace. The use of programmable network hardware to perform part of the processing at line rate can drastically increase the throughput while retaining the flexibility.This work presents a new framework, called CHIMA, which extends the capabilities of other frameworks proposed in the literature for the deployment of heterogeneous Service Function Chains (SFCs). Heterogeneous SFCs comprise a combination of virtual functions meant to be executed in containers running on general purpose hardware and of functions for programmable switches written using the P4 language. CHIMA exploits programmable data planes to perform real time monitoring of the services through In-band Network Telemetry and uses the collected information to guarantee the requested levels of performance by redeploying and rerouting sections that are affected by adverse conditions, allowing applications with critical requirements to be deployed as SFCs.The solution has been tested by emulating various topologies and services on the FOP4 platform with bmv2 switches. The analysis shows that the system is capable of detecting faults in the order of hundreds of milliseconds, and the overhead it causes in the process of redeployment is negligible compared to the startup time of functions. Measurements also reveal that the current bottleneck for the runtime relocation of heterogeneous functions is the redeployment and reconfiguration of P4 programs.","PeriodicalId":125799,"journal":{"name":"2022 IEEE 8th International Conference on Network Softwarization (NetSoft)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114336604","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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