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: "effective privacy amplification for secure classical communications"
  Abstract: We study the practical effectiveness of privacy amplification for classical key distribution schemes. We find that in contrast to quantum key distribution schemes, the high fidelity of the raw key generated in classical systems allow the users to always sift a secure shorter key if they have an upper bound on the eavesdropper probability to correctly guess the exchanged key bits. The number of privacy amplification iterations needed to achieve information leak of 10−8 in existing classical communicators is 2 or 3 resulting in a corresponding slowdown 4 to 8. We analyze the inherent tradeoff between the number of iterations and the security of the raw key. This property which is unique to classical key distribution systems render them highly useful for practical, especially for noisy channels where sufficiently low quantum bit error ratios are difficult to achieve.

Connected through hyperedge HE-1 (induced by source paper "comments on a new transient attack on the kish key distribution system"):
  with members:
    - "current injection attack against the kljn secure key exchange"
    - "analysis of an attenuator artifact in an experimental attack by gunn allison abbott against the kirchhoff law johnson noise kljn secure key exchange system"
    - "generalized kirchhoff law johnson noise kljn secure key exchange system using arbitrary resistors"
    - "cable capacitance attack against the kljn secure key exchange"
    - "on the security of the kirchhoff law johnson noise kljn communicator"
    - "on the cracking scheme in the paper a directional coupler attack against the kish key distribution system by gunn allison and abbott"
    - "elimination of a second law attack and all cable resistance based attacks in the kirchhoff law johnson noise kljn secure key exchange system"
    - "errors and their mitigation at the kirchhoff law johnson noise secure key exchange"

Connected through hyperedge HE-2 (induced by source paper "unconditionally secure credit debit card chip scheme and physical unclonable function"):
  with members:
    - "random resistor random temperature kirchhoff law johnson noise rrrt kljn key exchange"
    - "current injection attack against the kljn secure key exchange"
    - "generalized kirchhoff law johnson noise kljn secure key exchange system using arbitrary resistors"
    - "on the security of the kirchhoff law johnson noise kljn communicator"
    - "enhanced secure key exchange systems based on the johnson noise scheme"

Connected through hyperedge HE-3 (induced by source paper "current injection attack against the kljn secure key exchange"):
  with members:
    - "random resistor random temperature kirchhoff law johnson noise rrrt kljn key exchange"
    - "comments on a new transient attack on the kish key distribution system"
    - "resource requirements and speed versus geometry of unconditionally secure physical key exchanges"
    - "key exchange trust evaluation in peer to peer sensor networks with unconditionally secure key exchange"
    - "analysis of an attenuator artifact in an experimental attack by gunn allison abbott against the kirchhoff law johnson noise kljn secure key exchange system"
    - "on kljn based secure key distribution in vehicular communication networks"
    - "generalized kirchhoff law johnson noise kljn secure key exchange system using arbitrary resistors"
    - "cable capacitance attack against the kljn secure key exchange"

Connected through hyperedge HE-4 (induced by source paper "cable capacitance attack against the kljn secure key exchange"):
  with members:
    - "random resistor random temperature kirchhoff law johnson noise rrrt kljn key exchange"
    - "resource requirements and speed versus geometry of unconditionally secure physical key exchanges"
    - "analysis of an attenuator artifact in an experimental attack by gunn allison abbott against the kirchhoff law johnson noise kljn secure key exchange system"
    - "generalized kirchhoff law johnson noise kljn secure key exchange system using arbitrary resistors"
    - "current and voltage based bit errors and their combined mitigation for the kirchhoff law johnson noise secure key exchange"
    - "on the security of the kirchhoff law johnson noise kljn communicator"
    - "securing vehicle communication systems by the kljn key exchange protocol"
    - "on the cracking scheme in the paper a directional coupler attack against the kish key distribution system by gunn allison and abbott"

Connected through hyperedge HE-5 (induced by source paper "analysis of an attenuator artifact in an experimental attack by gunn allison abbott against the kirchhoff law johnson noise kljn secure key exchange system"):
  with members:
    - "current and voltage based bit errors and their combined mitigation for the kirchhoff law johnson noise secure key exchange"
    - "what kind of noise guarantees security for the kirchhoff law johnson noise key exchange"
    - "on the security of the kirchhoff law johnson noise kljn communicator"
    - "noise properties in the ideal kirchhoff law johnson noise secure communication system"
    - "on the cracking scheme in the paper a directional coupler attack against the kish key distribution system by gunn allison and abbott"
    - "elimination of a second law attack and all cable resistance based attacks in the kirchhoff law johnson noise kljn secure key exchange system"
    - "do electromagnetic waves exist in a short cable at low frequencies what does physics say"
    - "critical analysis of the bennett riedel attack on secure cryptographic key distributions via the kirchhoff law johnson noise scheme"

Connected through hyperedge HE-6 (induced by source paper "enhanced usage of keys obtained by physical unconditionally secure distributions"):
  with members:
    - "on the security of the kirchhoff law johnson noise kljn communicator"
    - "errors and their mitigation at the kirchhoff law johnson noise secure key exchange"

Connected through hyperedge HE-7 (induced by source paper "elimination of a second law attack and all cable resistance based attacks in the kirchhoff law johnson noise kljn secure key exchange system"):
  with members:
    - "current and voltage based bit errors and their combined mitigation for the kirchhoff law johnson noise secure key exchange"
    - "what kind of noise guarantees security for the kirchhoff law johnson noise key exchange"
    - "on the security of the kirchhoff law johnson noise kljn communicator"
    - "noise properties in the ideal kirchhoff law johnson noise secure communication system"
    - "on the cracking scheme in the paper a directional coupler attack against the kish key distribution system by gunn allison and abbott"
    - "do electromagnetic waves exist in a short cable at low frequencies what does physics say"
    - "enhanced secure key exchange systems based on the johnson noise scheme"
    - "critical analysis of the bennett riedel attack on secure cryptographic key distributions via the kirchhoff law johnson noise scheme"

Connected through hyperedge HE-8 (induced by source paper "on the cracking scheme in the paper a directional coupler attack against the kish key distribution system by gunn allison and abbott"):
  with members:
    - "what kind of noise guarantees security for the kirchhoff law johnson noise key exchange"
    - "noise properties in the ideal kirchhoff law johnson noise secure communication system"
    - "do electromagnetic waves exist in a short cable at low frequencies what does physics say"
    - "a directional coupler attack against the kish key distribution system"
    - "enhanced secure key exchange systems based on the johnson noise scheme"
    - "critical analysis of the bennett riedel attack on secure cryptographic key distributions via the kirchhoff law johnson noise scheme"

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)