human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "a survey on security metrics"):
  Abstract: The importance of security metrics can hardly be overstated. Despite the attention that has been paid by the academia, government and industry in the past decades, this important problem stubbornly remains open. In this survey, we present a survey of knowledge on security metrics. The survey is centered on a novel taxonomy, which classifies security metrics into four categories: metrics for measuring the system vulnerabilities, metrics for measuring the defenses, metrics for measuring the threats, and metrics for measuring the situations. The insight underlying the taxonomy is that situations (or outcomes of cyber attack-defense interactions) are caused by certain threats (or attacks) against systems that have certain vulnerabilities (including human factors) and employ certain defenses. In addition to systematically reviewing the security metrics that have been proposed in the literature, we discuss the gaps between the state of the art and the ultimate goals.

Includes members:
  Member "characterizing honeypot captured cyber attacks statistical framework and case study":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "metrics towards measuring cyber agility")
  Member "a stochastic model of active cyber defense dynamics":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "preventive and reactive cyber defense dynamics with ergodic time dependent parameters is globally attractive")
  Member "a characterization of cybersecurity posture from network telescope data":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "predicting cyber attack rates with extreme values")
  Member "an extended stochastic model for quantitative security analysis of networked systems":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "metrics towards measuring cyber agility")
  Member "predicting cyber attack rates with extreme values":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "metrics towards measuring cyber agility")
  Member "cyber epidemic models with dependences":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "a survey on ethereum systems security vulnerabilities attacks and defenses")
  Member "a new approach to modeling and analyzing security of networked systems":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "preventive and reactive cyber defense dynamics with ergodic time dependent parameters is globally attractive")
  Member "active cyber defense dynamics exhibiting rich phenomena":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "preventive and reactive cyber defense dynamics with ergodic time dependent parameters is globally attractive")

Question: Please tell me which class the source paper 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)