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: "the relay eavesdropper channel cooperation for secrecy"
  Abstract: This paper establishes the utility of user cooperation in facilitating secure wireless communications. In particular, the four-terminal relay-eavesdropper channel is introduced and an outer-bound on the optimal rate-equivocation region is derived. Several cooperation strategies are then devised and the corresponding achievable rate-equivocation region are characterized. Of particular interest is the novel Noise-Forwarding (NF) strategy, where the relay node sends codewords independent of the source message to confuse the eavesdropper. This strategy is used to illustrate the deaf helper phenomenon, where the relay is able to facilitate secure communications while being totally ignorant of the transmitted messages. Furthermore, NF is shown to increase the secrecy capacity in the reversely degraded scenario, where the relay node fails to offer performance gains in the classical setting. The gain offered by the proposed cooperation strategies is then proved theoretically and validated numerically in the additive White Gaussian Noise (AWGN) channel.

Connected through hyperedge HE-1 (induced by source paper "joint relay and jammer selection for secure two way relay networks"):
  with members:
    - "differential modulation for bi directional relaying with analog network coding"
    - "cooperative secret communication with artificial noise in symmetric interference channel"
    - "the role of feedback in two way secure communications"
    - "secrecy in cooperative relay broadcast channels"
    - "achievable rates for two way wire tap channels"
    - "achievable rates for the general gaussian multiple access wire tap channel with collective secrecy"

Connected through hyperedge HE-2 (induced by source paper "a secure communication game with a relay helping the eavesdropper"):
  with members:
    - "interference assisted secret communication"
    - "secrecy capacity of a class of orthogonal relay eavesdropper channels"
    - "mutual information games in multi user channels with correlated jamming"
    - "the gaussian multiple access wire tap channel"

Connected through hyperedge HE-3 (induced by source paper "improved rate equivocation regions for secure cooperative communication"):
  with members:
    - "interference assisted secret communication"
    - "the gaussian multiple access wire tap channel"

Connected through hyperedge HE-4 (induced by source paper "secrecy capacity of a class of orthogonal relay eavesdropper channels"):
  with members:
    - "secure transmission with multiple antennas ii the mimome wiretap channel"
    - "secure communication over fading channels"
    - "a note on the secrecy capacity of the multi antenna wiretap channel"
    - "the mimome channel"
    - "the secrecy capacity of the mimo wiretap channel"
    - "the general gaussian multiple access and two way wire tap channels achievable rates and cooperative jamming"
    - "relay channels with confidential messages"

Connected through hyperedge HE-5 (induced by source paper "cooperative jamming for wireless physical layer security"):
  with members:
    - "secrecy capacity of a class of orthogonal relay eavesdropper channels"
    - "the general gaussian multiple access and two way wire tap channels achievable rates and cooperative jamming"

Connected through hyperedge HE-6 (induced by source paper "on the secure degrees of freedom in the k user gaussian interference channel"):
  with members:
    - "secure transmission with multiple antennas ii the mimome wiretap channel"
    - "the wiretap channel with feedback encryption over the channel"
    - "discrete memoryless interference and broadcast channels with confidential messages secrecy rate regions"
    - "secure communication over fading channels"
    - "the mimome channel"
    - "the secrecy capacity of the mimo wiretap channel"
    - "cognitive interference channels with confidential messages"
    - "on the secrecy capacity of fading channels"

Connected through hyperedge HE-7 (induced by source paper "wireless secrecy in cellular systems with infrastructure aided cooperation"):
  with members:
    - "secure transmission with multiple antennas ii the mimome wiretap channel"
    - "discrete memoryless interference and broadcast channels with confidential messages secrecy rate regions"
    - "to decode the interference or to consider it as noise"
    - "the mimome channel"
    - "multiple antenna secure broadcast over wireless networks"
    - "the general gaussian multiple access and two way wire tap channels achievable rates and cooperative jamming"
    - "on the secrecy capacity of fading channels"

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)