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: "improving wireless physical layer security via exploiting co channel interference"
  Abstract: This paper considers a scenario in which a source–destination pair needs to establish a confidential connection against an external eavesdropper, aided by the interference generated by another source–destination pair that exchanges public messages. The goal is to compute the maximum achievable secrecy degrees of freedom (S.D.o.F) region of a MIMO two-user wiretap network. First, a cooperative secrecy transmission scheme is proposed, whose feasible set is shown to achieve all S.D.o.F. pairs on the S.D.o.F. region boundary. In this way, the determination of the S.D.o.F. region is reduced to a problem of maximizing the S.D.o.F. pair over the proposed transmission scheme. The maximum achievable S.D.o.F. region boundary points are obtained in closed form, and the construction of the precoding matrices achieving the maximum S.D.o.F. region boundary is provided. The proposed expressions are functions of the number of antennas at each terminal, and apply to any number of antennas, thus constituting an advancement over prior works that have considered only fixed antenna configurations.

Connected through hyperedge HE-1 (induced by source paper "mimo secret communications against an active eavesdropper"):
  with members:
    - "secure degrees of freedom regions of multiple access and interference channels the polytope structure"
    - "linear precoding of data and artificial noise in secure massive mimo systems"
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "secure massive mimo transmission in the presence of an active eavesdropper"
    - "secure degrees of freedom of one hop wireless networks"
    - "improving physical layer secrecy using full duplex jamming receivers"
    - "secure degrees of freedom of k user gaussian interference channels a unified view"

Connected through hyperedge HE-2 (induced by source paper "linear precoder design for a mimo gaussian wiretap channel with full duplex source and destination nodes"):
  with members:
    - "joint power control in wiretap interference channels"
    - "secrecy transmit beamforming for heterogeneous networks"
    - "resource allocation in full duplex communications for future wireless networks"
    - "improving physical layer secrecy using full duplex jamming receivers"
    - "in band full duplex wireless challenges and opportunities"
    - "mimo interference alignment over correlated channels with imperfect csi"
    - "interference alignment for secrecy"
    - "solutions for the mimo gaussian wiretap channel with a cooperative jammer"

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)