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: "delivery secrecy tradeoff for cache enabled stochastic networks content placement optimization"
  Abstract: Wireless caching has been widely recognized as a promising technique for efficient content delivery. In this paper, by taking different file secrecy levels into consideration, physical-layer security oriented content placement is optimized in a stochastic cache-enabled cellular network. We propose an analytical framework to investigate the nontrivial file delivery-secrecy tradeoff. Specifically, we first derive the closed-form expressions for the file hit and secrecy probabilities. The global optimal probabilistic content placement policy is then analytically derived in terms of hit probability maximization under file secrecy constraints. Numerical results are demonstrated to verify our analytical findings and show that the targeted file secrecy levels are crucial in balancing the file delivery-secrecy tradeoff.

Connected through hyperedge HE-1 (induced by source paper "enhancing physical layer security of random caching in large scale multi antenna heterogeneous wireless networks"):
  with members:
    - "secure and energy efficient transmissions in cache enabled heterogeneous cellular networks performance analysis and optimization"
    - "enhancing performance of random caching in large scale wireless networks with multiple receive antennas"
    - "physical layer security in cache enabled cooperative small cell networks against randomly distributed eavesdroppers"
    - "a unified framework for the tractable analysis of multi antenna wireless networks"
    - "enhancing performance of random caching in large scale heterogeneous wireless networks with random discontinuous transmission"
    - "random caching based cooperative transmission in heterogeneous wireless networks"
    - "caching at the wireless edge design aspects challenges and future directions"
    - "optimal content placement for offloading in cache enabled heterogeneous wireless networks"

Connected through hyperedge HE-2 (induced by source paper "secrecy transmission in large scale uav enabled wireless networks"):
  with members:
    - "a survey of optimization approaches for wireless physical layer security"
    - "exploiting noma oma for multi uav communications in large scale networks"
    - "exploiting noma for uav communications in large scale cellular networks"
    - "capacity characterization of uav enabled two user broadcast channel"
    - "securing uav communications via joint trajectory and power control"
    - "cellular enabled uav communication a connectivity constrained trajectory optimization perspective"
    - "ultra reliable uav communication using altitude and cooperation diversity"
    - "physical layer security in cache enabled cooperative small cell networks against randomly distributed eavesdroppers"

Connected through hyperedge HE-3 (induced by source paper "the stochastic geometry analyses of cellular networks with alpha stable self similarity"):
  with members:
    - "system level modeling and optimization of the energy efficiency in cellular networks a stochastic geometry framework"
    - "self interference in full duplex multi user mimo channels"
    - "secrecy outage analysis for downlink transmissions in the presence of randomly located eavesdroppers"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "analytical modeling of interference aware power control for the uplink of heterogeneous cellular networks"
    - "analysis of massive mimo enabled downlink wireless backhauling for full duplex small cells"
    - "the learning and prediction of application level traffic data in cellular networks"
    - "opportunistic jamming for enhancing security stochastic geometry modeling and analysis"

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)