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: "current injection attack against the kljn secure key exchange"
  Abstract: The Kirchhoff-law-Johnson-noise (KLJN) scheme is a statistical/physical secure key exchange system based on the laws of classical statistical physics to provide unconditional security. We used the LTSPICE industrial cable and circuit simulator to emulate one of the major active (invasive) attacks, the current injection attack, against the ideal and a practical KLJN system, respectively. We show that two security enhancement techniques, namely, the instantaneous voltage/current comparison method, and a simple privacy amplification scheme, independently and effectively eliminate the information leak and successfully preserve the system's unconditional security.

Connected through hyperedge HE-1 (induced by source paper "generalized dc loop current attack against the kljn secure key exchange scheme"):
  with members:
    - "random resistor random temperature kirchhoff law johnson noise rrrt kljn key exchange"
    - "unconditionally secure credit debit card chip scheme and physical unclonable function"
    - "comments on a new transient attack on the kish key distribution system"
    - "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"
    - "on the security of the kirchhoff law johnson noise kljn communicator"

Connected through hyperedge HE-2 (induced by source paper "a static loop current attack against the kljn secure key exchange system"):
  with members:
    - "random resistor random temperature kirchhoff law johnson noise rrrt kljn key exchange"
    - "unconditionally secure credit debit card chip scheme and physical unclonable function"
    - "comments on a new transient attack on the kish key distribution system"
    - "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"
    - "securing vehicle communication systems by the kljn key exchange protocol"
    - "elimination of a second law attack and all cable resistance based attacks in the kirchhoff law johnson noise kljn secure key exchange system"

Connected through hyperedge HE-3 (induced by source paper "comments on a new transient attack on the kish key distribution system"):
  with members:
    - "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"
    - "enhanced secure key exchange systems based on the johnson noise scheme"

Connected through hyperedge HE-4 (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"
    - "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"
    - "effective privacy amplification for secure classical communications"

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)