human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "an extended stochastic model for quantitative security analysis of networked systems"
  Abstract: Quantitative security analysis of networked computer systems is one of the decades-long open problems in computer security. Recently, a promising approach was proposed in \cite{XuTDSC11}, which however made some strong assumptions including the exponential distribution of, and the independence between, the relevant random variables. In this paper, we substantially weaken these assumptions while offering, in addition to the same types of analytical results as in \cite{XuTDSC11}, methods for obtaining the desired security quantities in practice. Moreover, we investigate the problem from a higher-level abstraction, which also leads to both analytical results and practical methods for obtaining the desired security quantities. These would represent a significant step toward ultimately solving the problem of quantitative security analysis of networked computer systems.

Connected through hyperedge HE-1 (induced by source paper "metrics towards measuring cyber agility"):
  with members:
    - "characterizing honeypot captured cyber attacks statistical framework and case study"
    - "a stochastic model of active cyber defense dynamics"
    - "push and pull based epidemic spreading in networks thresholds and deeper insights"
    - "optimizing active cyber defense"
    - "predicting cyber attack rates with extreme values"
    - "cyber epidemic models with dependences"
    - "a new approach to modeling and analyzing security of networked systems"
    - "active cyber defense dynamics exhibiting rich phenomena"

Connected through hyperedge HE-2 (induced by source paper "a survey on security metrics"):
  with members:
    - "characterizing honeypot captured cyber attacks statistical framework and case study"
    - "a stochastic model of active cyber defense dynamics"
    - "a characterization of cybersecurity posture from network telescope data"
    - "predicting cyber attack rates with extreme values"
    - "cyber epidemic models with dependences"
    - "a new approach to modeling and analyzing security of networked systems"
    - "active cyber defense dynamics exhibiting rich phenomena"
    - "characterizing the power of moving target defense via cyber epidemic dynamics"

Connected through hyperedge HE-3 (induced by source paper "preventive and reactive cyber defense dynamics is globally stable"):
  with members:
    - "a stochastic model of active cyber defense dynamics"
    - "a stochastic model for quantitative security analyses of networked systems"
    - "cyber epidemic models with dependences"
    - "a new approach to modeling and analyzing security of networked systems"
    - "active cyber defense dynamics exhibiting rich phenomena"
    - "characterizing the power of moving target defense via cyber epidemic dynamics"

Connected through hyperedge HE-4 (induced by source paper "active cyber defense dynamics exhibiting rich phenomena"):
  with members:
    - "a stochastic model of active cyber defense dynamics"
    - "push and pull based epidemic spreading in networks thresholds and deeper insights"
    - "optimizing active cyber defense"
    - "a new approach to modeling and analyzing security of networked systems"
    - "characterizing the power of moving target defense via cyber epidemic dynamics"

Connected through hyperedge HE-5 (induced by source paper "a new approach to modeling and analyzing security of networked systems"):
  with members:
    - "a stochastic model of active cyber defense dynamics"
    - "a stochastic model for quantitative security analyses of networked systems"
    - "push and pull based epidemic spreading in networks thresholds and deeper insights"
    - "cyber epidemic models with dependences"

Connected through hyperedge HE-6 (induced by source paper "cyber epidemic models with dependences"):
  with members:
    - "a stochastic model for quantitative security analyses of networked systems"
    - "push and pull based epidemic spreading in networks thresholds and deeper insights"
    - "a new approach to modeling and analyzing security of networked systems"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.CR(Cryptography and Security)