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: "secrecy capacity of a class of orthogonal relay eavesdropper channels"
  Abstract: The secrecy capacity of relay channels with orthogonal components is studied in the presence of an additional passive eavesdropper node. The relay and destination receive signals from the source on two orthogonal channels such that the destination also receives transmissions from the relay on its channel. The eavesdropper can overhear either one or both of the orthogonal channels. Inner and outer bounds on the secrecy capacity are developed for both the discrete memoryless and the Gaussian channel models. For the discrete memoryless case, the secrecy capacity is shown to be achieved by a partial decode-and-forward (PDF) scheme when the eavesdropper can overhear only one of the two orthogonal channels. Two new outer bounds are presented for the Gaussian model using recent capacity results for a Gaussian multiantenna point-to-point channel with a multiantenna eavesdropper. The outer bounds are shown to be tight for two subclasses of channels. The first subclass is one in which the source and relay are clustered, and the eavesdropper receives signals only on the channel from the source and the relay to the destination, for which the PDF strategy is optimal. The second is a subclass in which the source does not transmit to the relay, for which a noise-forwarding strategy is optimal.

Connected through hyperedge HE-1 (induced by source paper "secure communication with a wireless powered friendly jammer"):
  with members:
    - "secrecy wireless information and power transfer in fading wiretap channel"
    - "wireless powered communication opportunities and challenges"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "cutting last wires for mobile communication by microwave power transfer"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "principles of physical layer security in multiuser wireless networks a survey"

Connected through hyperedge HE-2 (induced by source paper "on the capacity of the 2 user interference channel with transmitter cooperation and secrecy constraints"):
  with members:
    - "secrecy in the 2 user symmetric deterministic interference channel with transmitter cooperation"
    - "multiaccess channel with partially cooperating encoders and security constraints"
    - "interference alignment for secrecy"
    - "secret writing on dirty paper a deterministic view"
    - "interference assisted secret communication"
    - "interference mitigation through limited transmitter cooperation"
    - "interference mitigation through limited receiver cooperation"
    - "secrecy in cooperative relay broadcast channels"

Connected through hyperedge HE-3 (induced by source paper "multiaccess channel with partially cooperating encoders and security constraints"):
  with members:
    - "secure communication over parallel relay channel"
    - "interference assisted secret communication"
    - "cooperation with an untrusted relay a secrecy perspective"
    - "providing secrecy with structured codes tools and applications to two user gaussian channels"
    - "discrete memoryless interference and broadcast channels with confidential messages secrecy rate regions"
    - "the gaussian mac with conferencing encoders"
    - "the secrecy capacity of the mimo wiretap channel"
    - "the gaussian multiple access wire tap channel"

Connected through hyperedge HE-4 (induced by source paper "truthful mechanisms for secure communication in wireless cooperative system"):
  with members:
    - "on cooperative relaying schemes for wireless physical layer security"
    - "joint relay and jammer selection for secure two way relay networks"
    - "cooperative jamming for secure communications in mimo relay networks"

Connected through hyperedge HE-5 (induced by source paper "secure communication over parallel relay channel"):
  with members:
    - "cooperation with an untrusted relay a secrecy perspective"
    - "secure transmission with multiple antennas ii the mimome wiretap channel"
    - "the secrecy capacity of the mimo wiretap channel"
    - "the gaussian multiple access wire tap channel"

Connected through hyperedge HE-6 (induced by source paper "on cooperative relaying schemes for wireless physical layer security"):
  with members:
    - "optimal and robust transmit designs for miso channel secrecy by semidefinite programming"
    - "secure transmission with multiple antennas ii the mimome wiretap channel"
    - "the ergodic capacity of the mimo wire tap channel"
    - "the mimome channel"
    - "the secrecy capacity of the mimo wiretap channel"

Connected through hyperedge HE-7 (induced by source paper "a secure communication game with a relay helping the eavesdropper"):
  with members:
    - "interference assisted secret communication"
    - "mutual information games in multi user channels with correlated jamming"
    - "the relay eavesdropper channel cooperation for secrecy"
    - "the gaussian multiple access wire tap channel"

Connected through hyperedge HE-8 (induced by source paper "collaborative relay beamforming for secrecy"):
  with members:
    - "achieving the secrecy capacity of wiretap channels using polar codes"
    - "secure communication in the low snr regime a characterization of the energy secrecy tradeoff"
    - "on the relationship between the multi antenna secrecy communications and cognitive radio communications"
    - "discrete memoryless interference and broadcast channels with confidential messages secrecy rate regions"
    - "network beamforming using relays with perfect channel information"
    - "secrecy capacity region of a multi antenna gaussian broadcast channel with confidential messages"
    - "on the secrecy capacity of fading channels"
    - "applications of ldpc codes to the wiretap channel"

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.IT(Information Theory)