Pub Date : 2005-04-18DOI: 10.1109/NGI.2005.1431660
Marcin Lubonski, V. Gay, A. Simmonds
Limitations in the contemporary best effort WAN combined with an increase in demand of the business users for multimedia are the main challenges for remote desktop solutions. Thin client remote desktop protocols are now mature enough to work efficiently over low bandwidth and low quality links for normal office applications. However, they face significant challenges when working with more demanding data flows such as multimedia streams. This paper introduces the server-side component of the architecture for remote desktop environment aiming at improving user perception of the more demanding and network sensitive multimedia applications and services. Our component maps of user-perceived quality of service (QoS) onto network-level performance parameters in order to improve overall end-to-end QoS. The set of perception rules defined for each application and type of user triggers the adaptation mechanisms to change the transmission parameters in order to meet end user expectations. The adaptation mechanisms can optimize the usage of the available network resources within a dedicated network link both for different flows within single client connection and for all clients connected to the same server module. The result of such an optimization is a new set of connection parameters adjusted to network state changes and user perception of remote desktop. In the paper we discuss requirements of such QoS control mechanisms and respective adaptation mechanisms, followed by the detailed description of the proposed component architecture.
{"title":"An adaptation architecture to improve QoS of multimedia services for enterprise remote desktop protocols","authors":"Marcin Lubonski, V. Gay, A. Simmonds","doi":"10.1109/NGI.2005.1431660","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431660","url":null,"abstract":"Limitations in the contemporary best effort WAN combined with an increase in demand of the business users for multimedia are the main challenges for remote desktop solutions. Thin client remote desktop protocols are now mature enough to work efficiently over low bandwidth and low quality links for normal office applications. However, they face significant challenges when working with more demanding data flows such as multimedia streams. This paper introduces the server-side component of the architecture for remote desktop environment aiming at improving user perception of the more demanding and network sensitive multimedia applications and services. Our component maps of user-perceived quality of service (QoS) onto network-level performance parameters in order to improve overall end-to-end QoS. The set of perception rules defined for each application and type of user triggers the adaptation mechanisms to change the transmission parameters in order to meet end user expectations. The adaptation mechanisms can optimize the usage of the available network resources within a dedicated network link both for different flows within single client connection and for all clients connected to the same server module. The result of such an optimization is a new set of connection parameters adjusted to network state changes and user perception of remote desktop. In the paper we discuss requirements of such QoS control mechanisms and respective adaptation mechanisms, followed by the detailed description of the proposed component architecture.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116736558","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431699
Mahnhoon Lee, Y. Yoon
As a result of the slow deployment of IPv6, many new proposals have been presented for the next generation Internet or to expand the IPv4 Internet. But none of them except NAT has been deployed successfully, mainly due to the requirement of modification of hosts and/or routers and the lack of scalable accessibility from the public IPv4 Internet to their realms. Recently UNA was presented to provide that scalable accessibility, with no modification of routers and hosts. It is still anticipated, however, that it would take a long time until IPv6 or other technology replaces IPv4 entirely. But it is urgent that the address space shortage problem be solved and that value-added services such as QoS and mobility be provided. In this paper, we discuss about the reorganization of the IPv4 Internet into a multi-tier architecture as a possible way of evolving the Internet, which can support a larger address space and deal with security, QoS, multicast, mobility and so on. As such an architecture, we present MTI (Multi-Tier Internet), in which UNA and MTAII are integrated, without forcing any modification of routers and hosts for easy deployment.
{"title":"MTI: integration of UNA and MTAII toward the next generation Internet","authors":"Mahnhoon Lee, Y. Yoon","doi":"10.1109/NGI.2005.1431699","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431699","url":null,"abstract":"As a result of the slow deployment of IPv6, many new proposals have been presented for the next generation Internet or to expand the IPv4 Internet. But none of them except NAT has been deployed successfully, mainly due to the requirement of modification of hosts and/or routers and the lack of scalable accessibility from the public IPv4 Internet to their realms. Recently UNA was presented to provide that scalable accessibility, with no modification of routers and hosts. It is still anticipated, however, that it would take a long time until IPv6 or other technology replaces IPv4 entirely. But it is urgent that the address space shortage problem be solved and that value-added services such as QoS and mobility be provided. In this paper, we discuss about the reorganization of the IPv4 Internet into a multi-tier architecture as a possible way of evolving the Internet, which can support a larger address space and deal with security, QoS, multicast, mobility and so on. As such an architecture, we present MTI (Multi-Tier Internet), in which UNA and MTAII are integrated, without forcing any modification of routers and hosts for easy deployment.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"282 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131521291","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431670
S. Oueslati, J. Roberts
In this paper we present the architectural implications of flow-aware networking, or FAN, a new approach for realizing QoS guarantees. FAN performs traffic control based on user-defined flows using implicit admission control and per-flow scheduling. This allows adequate performance guarantees for streaming and elastic flows without requiring class of service distinction or relying on signalled traffic specifications. We argue that FAN is a new direction for Internet quality of service that is arguably necessary as an alternative to flawed classical architectures and sufficient to meet user performance requirements in a cost-effective way.
{"title":"A new direction for quality of service: flow-aware networking","authors":"S. Oueslati, J. Roberts","doi":"10.1109/NGI.2005.1431670","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431670","url":null,"abstract":"In this paper we present the architectural implications of flow-aware networking, or FAN, a new approach for realizing QoS guarantees. FAN performs traffic control based on user-defined flows using implicit admission control and per-flow scheduling. This allows adequate performance guarantees for streaming and elastic flows without requiring class of service distinction or relying on signalled traffic specifications. We argue that FAN is a new direction for Internet quality of service that is arguably necessary as an alternative to flawed classical architectures and sufficient to meet user performance requirements in a cost-effective way.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115052446","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431657
J. Joutsensalo, Timo Hämäläinen, Jarmo Siltanen, K. Luostarinen
This paper presents a packet scheduling scheme for ensuring delay and bandwidth as a quality of service (QoS) requirement. For customers, rightful service is given while optimizing revenue of the network service provider. A gradient and fixed point type algorithms for updating the weights of a packet scheduler are derived from a revenue-based optimization problem. In the linear pricing scenario, algorithms are simple to implement. We compared algorithms with optimal brute-force method. Especially fixed point algorithm converges very fast to the optimal solution, typically in one iteration and about 40 operations, when number of classes is three. The weight updating procedures are independent on the assumption of the connections' statistical behavior, and therefore they are robust against erroneous estimates of statistics. Also, a call admission control (CAC) is implemented in context of our scenario.
{"title":"Delay guarantee and bandwidth allocation for network services","authors":"J. Joutsensalo, Timo Hämäläinen, Jarmo Siltanen, K. Luostarinen","doi":"10.1109/NGI.2005.1431657","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431657","url":null,"abstract":"This paper presents a packet scheduling scheme for ensuring delay and bandwidth as a quality of service (QoS) requirement. For customers, rightful service is given while optimizing revenue of the network service provider. A gradient and fixed point type algorithms for updating the weights of a packet scheduler are derived from a revenue-based optimization problem. In the linear pricing scenario, algorithms are simple to implement. We compared algorithms with optimal brute-force method. Especially fixed point algorithm converges very fast to the optimal solution, typically in one iteration and about 40 operations, when number of classes is three. The weight updating procedures are independent on the assumption of the connections' statistical behavior, and therefore they are robust against erroneous estimates of statistics. Also, a call admission control (CAC) is implemented in context of our scenario.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129641857","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431678
K. Tutschku, T. Hossfeld, H. Meer, Jens O. Oberender, Frank-Uwe Andersen
Peer-to-peer (P2P) file-sharing has become the killer application in the wired Internet and might also be highly attractive for mobile networks. In particular since UMTS operators are searching for new applications which do both: a) exploit the potential of the UMTS technology and b) motivate the user to adopt the new technology. In this work we are investigating the performance of an eDonkey-based mobile P2P file-sharing system by means of time-dynamic simulation. Mobile networks differ from wireline networks by the limited capacity of the radio link and the mobility of the users. P2P networks, in contrast, are overlays which consider the transport network in an abstract way. In a mobile environment, the question arises, whether the abstraction can be maintained and what will be the performance impact if there is any. We will show in detail how the mobile access technology (GPRS or UMTS), the churn behavior of mobile users, the file size of mobile specific content, and special infrastructure entities, such as a cache peer, influences the performance of the suggested mobile P2P file-sharing service.
{"title":"Simulative performance evaluation of a mobile peer-to-peer file-sharing system","authors":"K. Tutschku, T. Hossfeld, H. Meer, Jens O. Oberender, Frank-Uwe Andersen","doi":"10.1109/NGI.2005.1431678","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431678","url":null,"abstract":"Peer-to-peer (P2P) file-sharing has become the killer application in the wired Internet and might also be highly attractive for mobile networks. In particular since UMTS operators are searching for new applications which do both: a) exploit the potential of the UMTS technology and b) motivate the user to adopt the new technology. In this work we are investigating the performance of an eDonkey-based mobile P2P file-sharing system by means of time-dynamic simulation. Mobile networks differ from wireline networks by the limited capacity of the radio link and the mobility of the users. P2P networks, in contrast, are overlays which consider the transport network in an abstract way. In a mobile environment, the question arises, whether the abstraction can be maintained and what will be the performance impact if there is any. We will show in detail how the mobile access technology (GPRS or UMTS), the churn behavior of mobile users, the file size of mobile specific content, and special infrastructure entities, such as a cache peer, influences the performance of the suggested mobile P2P file-sharing service.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129884459","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431689
P. Chołda, A. Jajszczyk
Interesting and promising recovery techniques suited for the next generation Internet are studied: traditional protection rings and the novel, preconfigured protection cycles (p-cycles) technique. We show that although p-cycles are better than traditional protection rings in terms of cost-effectiveness (redundancy), the latter surpass the former when the reliability measures are taken into account. We suggest that this fact be considered during network planning.
{"title":"Reliability assessment of rings and p-cycles in DWDM networks","authors":"P. Chołda, A. Jajszczyk","doi":"10.1109/NGI.2005.1431689","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431689","url":null,"abstract":"Interesting and promising recovery techniques suited for the next generation Internet are studied: traditional protection rings and the novel, preconfigured protection cycles (p-cycles) technique. We show that although p-cycles are better than traditional protection rings in terms of cost-effectiveness (redundancy), the latter surpass the former when the reliability measures are taken into account. We suggest that this fact be considered during network planning.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125969017","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431643
Dominique Barth, Lélia Blin, L. Echabbi, S. Vial
In this paper we deal with inter-domain routing management from an economical point of view. We present a game theory based costing model that maps BGP peers (autonomous systems belonging to different operators) into a strategic (selfish) agents competing for transit traffic as a service provided and charged to their peers. Indeed, in our model each operator fixes a price to each neighbor for each transit traffic unit. Then, BGP routing choice is made based on a minimum cost criterion where the goal of each operator is to minimize its costs. We investigate some particular strategies of updating prices that operators can use locally in order to minimize their costs. We focus on BGP stabilization properties related to such strategies from a simulation point of view.
{"title":"Distributed cost management in a selfish multi-operators BGP network","authors":"Dominique Barth, Lélia Blin, L. Echabbi, S. Vial","doi":"10.1109/NGI.2005.1431643","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431643","url":null,"abstract":"In this paper we deal with inter-domain routing management from an economical point of view. We present a game theory based costing model that maps BGP peers (autonomous systems belonging to different operators) into a strategic (selfish) agents competing for transit traffic as a service provided and charged to their peers. Indeed, in our model each operator fixes a price to each neighbor for each transit traffic unit. Then, BGP routing choice is made based on a minimum cost criterion where the goal of each operator is to minimize its costs. We investigate some particular strategies of updating prices that operators can use locally in order to minimize their costs. We focus on BGP stabilization properties related to such strategies from a simulation point of view.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"192 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127650555","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431687
Igor Margasi, K. Szczypiorski, Krzysztof M. Brzezi
Intrusions into the privacy of Web users, launched on a massive scale mostly to get commercial advantage, are not only annoying, but also start to hinder the further development of the Web and its accepted commercial uses. In this paper we seek the efficient ways of implementing privacy by assuring anonymity understood as unlinkability-the impossibility to reliably correlate the visible communication with a particular user. We briefly survey the state of the art and identify the deficiencies of existing anonymity solutions. We then submit the original approach to anonymity assurance: the VAST system, which is based on a particular unlinkability notion-the impossibility to reliably correlate communication with the intentional behaviour of a particular user.
{"title":"Private wars in secret life","authors":"Igor Margasi, K. Szczypiorski, Krzysztof M. Brzezi","doi":"10.1109/NGI.2005.1431687","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431687","url":null,"abstract":"Intrusions into the privacy of Web users, launched on a massive scale mostly to get commercial advantage, are not only annoying, but also start to hinder the further development of the Web and its accepted commercial uses. In this paper we seek the efficient ways of implementing privacy by assuring anonymity understood as unlinkability-the impossibility to reliably correlate the visible communication with a particular user. We briefly survey the state of the art and identify the deficiencies of existing anonymity solutions. We then submit the original approach to anonymity assurance: the VAST system, which is based on a particular unlinkability notion-the impossibility to reliably correlate communication with the intentional behaviour of a particular user.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"228 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131418822","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431679
D. García-Roger, M. J. Doménech-Benlloch, J. Martínez-Bauset, V. Pla
We propose a novel adaptive scheme that operates in association with either of two admission control policies, the multiple guard channel (MGC) and the multiple fractional guard channel (MFGC) policies. We provide two different implementations of the scheme, which adapt the configuration parameters of the associated policy according to the perceived QoS. The numerical evaluation carried out shows that the QoS objective is met with an excellent precision and the convergence period is much shorter than in previous proposals (approximately in the range of a thousand seconds), confirming that our approach can satisfactorily deal with the nonstationarity of an operating network. Two other key features of our scheme are its simplicity and time independency.
{"title":"Adaptive admission control scheme for multiservice mobile cellular networks","authors":"D. García-Roger, M. J. Doménech-Benlloch, J. Martínez-Bauset, V. Pla","doi":"10.1109/NGI.2005.1431679","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431679","url":null,"abstract":"We propose a novel adaptive scheme that operates in association with either of two admission control policies, the multiple guard channel (MGC) and the multiple fractional guard channel (MFGC) policies. We provide two different implementations of the scheme, which adapt the configuration parameters of the associated policy according to the perceived QoS. The numerical evaluation carried out shows that the QoS objective is met with an excellent precision and the convergence period is much shorter than in previous proposals (approximately in the range of a thousand seconds), confirming that our approach can satisfactorily deal with the nonstationarity of an operating network. Two other key features of our scheme are its simplicity and time independency.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131456999","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431661
K. Lója, J. Szigeti, T. Cinkler
Multiprovider inter-domain routing can be modeled using game theory, since the domains (or the domain operators) act as players trying to maximize their revenues. Each domain decides what intra-domain connection alternatives it advertises for inter-domain traffic and what the key attributes are of these intra-domain connections (allocation cost, latency, bandwidth or confidence level of availability). The advertised parameters affect the routing algorithm, the selected inter-domain path as well as the payoff of all the operators. As the broadband communication networks become optical, our model assumes a two layer network consisting of autonomous domains, where the optical cross-connects have limited wavelength conversion capability. In this paper we study the dependency of the domain income and the advertised cost of connection alternatives, assuming "cheapest-path" routing. We examined basic scenarios of inter-domain routing and determined Nash and Pareto equilibrium for different network load levels, where provider tariffs and end-user satisfaction were taken into account simultaneously. Beside analytical results, we ran simulations which met our expectations.
{"title":"Inter-domain routing in multiprovider optical networks: game theory and simulations","authors":"K. Lója, J. Szigeti, T. Cinkler","doi":"10.1109/NGI.2005.1431661","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431661","url":null,"abstract":"Multiprovider inter-domain routing can be modeled using game theory, since the domains (or the domain operators) act as players trying to maximize their revenues. Each domain decides what intra-domain connection alternatives it advertises for inter-domain traffic and what the key attributes are of these intra-domain connections (allocation cost, latency, bandwidth or confidence level of availability). The advertised parameters affect the routing algorithm, the selected inter-domain path as well as the payoff of all the operators. As the broadband communication networks become optical, our model assumes a two layer network consisting of autonomous domains, where the optical cross-connects have limited wavelength conversion capability. In this paper we study the dependency of the domain income and the advertised cost of connection alternatives, assuming \"cheapest-path\" routing. We examined basic scenarios of inter-domain routing and determined Nash and Pareto equilibrium for different network load levels, where provider tariffs and end-user satisfaction were taken into account simultaneously. Beside analytical results, we ran simulations which met our expectations.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132187669","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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