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: "secure communication over parallel relay channel"
  Abstract: We investigate the problem of secure communication over parallel relay channel in the presence of a passive eavesdropper. We consider a four-terminal relay-eavesdropper channel which consists of multiple relay-eavesdropper channels as subchannels. For the discrete memoryless model, we establish outer and inner bounds on the rate-equivocation region. The inner bound allows mode selection at the relay. For each subchannel, secure transmission is obtained through one of two coding schemes at the relay: decoding-and-forwarding the source message or confusing the eavesdropper through noise injection. For the Gaussian memoryless channel, we establish lower and upper bounds on the perfect secrecy rate. Furthermore, we study a special case in which the relay does not hear the source and show that under certain conditions the lower and upper bounds coincide. The results established for the parallel Gaussian relay-eavesdropper channel are then applied to study the fading relay-eavesdropper channel. Analytical results are illustrated through some numerical examples.

Connected through hyperedge HE-1 (induced by source paper "the arbitrarily varying relay channel"):
  with members:
    - "the capacity of the relay channel solution to cover s problem in the gaussian case"
    - "arbitrarily varying wiretap channels with type constrained states"
    - "cut set bound is loose for gaussian relay networks"
    - "the arbitrarily varying wiretap channel secret randomness stability and super activation"
    - "on the continuity of the secrecy capacity of compound and arbitrarily varying wiretap channels"
    - "capacity approximations for gaussian relay networks"
    - "the arbitrarily varying multiple access channel with conferencing encoders"
    - "achieving the capacity of the n relay gaussian diamond network within log n bits"

Connected through hyperedge HE-2 (induced by source paper "pilot spoofing attack by multiple eavesdroppers"):
  with members:
    - "admm based fast algorithm for multi group multicast beamforming in large scale wireless systems"
    - "impact of artificial noise on cellular networks a stochastic geometry approach"
    - "an algorithm for global maximization of secrecy rates in gaussian mimo wiretap channels"
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security in massive mimo"
    - "secret key agreement with large antenna arrays under the pilot contamination attack"
    - "securing massive mimo at the physical layer"
    - "robust secure transmission in miso channels based on worst case optimization"

Connected through hyperedge HE-3 (induced by source paper "resource allocation for secure gaussian parallel relay channels with finite length coding and discrete constellations"):
  with members:
    - "enhancing physical layer security in af relay assisted multicarrier wireless transmission enhancing physical layer security in af relay assisted multicarrier wireless transmission"
    - "joint relay selection and power allocation in large scale mimo systems with untrusted relays and passive eavesdroppers"
    - "secrecy optimized resource allocation for device to device communication underlaying heterogeneous networks"
    - "optimal power allocation by imperfect hardware analysis in untrusted relaying networks"
    - "secure and reliable transmission with cooperative relays in two hop wireless networks"
    - "on secrecy rate analysis of mimo wiretap channels driven by finite alphabet input"
    - "on cooperative relaying schemes for wireless physical layer security"
    - "sum rate maximized resource allocation in multiple df relays aided ofdm transmission"

Connected through hyperedge HE-4 (induced by source paper "secure degrees of freedom of wireless x networks using artificial noise alignment"):
  with members:
    - "secure degrees of freedom of one hop wireless networks"
    - "multiaccess channel with partially cooperating encoders and security constraints"
    - "secure degrees of freedom of k user gaussian interference channels a unified view"
    - "secure degrees of freedom of mimo x channels with output feedback and delayed csit"
    - "on x channels with feedback and delayed csi"
    - "on achievable degrees of freedom for mimo x channels"
    - "interference alignment for secrecy"
    - "interference assisted secret communication"

Connected through hyperedge HE-5 (induced by source paper "on sdof of multi receiver wiretap channel with alternating csit"):
  with members:
    - "on miso broadcast channel with alternating csit and secrecy constraints"
    - "secure degrees of freedom region of the two user miso broadcast channel with alternating csit"
    - "multiaccess channel with partially cooperating encoders and security constraints"
    - "new results on multiple input multiple output broadcast channels with confidential messages"
    - "secure degrees of freedom of mimo x channels with output feedback and delayed csit"
    - "degrees of freedom of time correlated miso broadcast channel with delayed csit"
    - "optimal use of current and outdated channel state information degrees of freedom of the miso bc with mixed csit"
    - "interference alignment for the mimo interference channel with delayed local csit"

Connected through hyperedge HE-6 (induced by source paper "interplay between delayed csit and network topology for secure miso bc"):
  with members:
    - "topological interference management through index coding"
    - "new results on multiple input multiple output broadcast channels with confidential messages"
    - "secure degrees of freedom of mimo x channels with output feedback and delayed csit"
    - "interference alignment for secrecy"
    - "interference alignment for the mimo interference channel with delayed local csit"
    - "secrecy degrees of freedom of mimo broadcast channels with delayed csit"
    - "completely stale transmitter channel state information is still very useful"
    - "on secure transmission over parallel relay eavesdropper channel"

Connected through hyperedge HE-7 (induced by source paper "on miso broadcast channel with alternating csit and secrecy constraints"):
  with members:
    - "multiaccess channel with partially cooperating encoders and security constraints"
    - "new results on multiple input multiple output broadcast channels with confidential messages"
    - "secure degrees of freedom of mimo x channels with output feedback and delayed csit"
    - "degrees of freedom of time correlated miso broadcast channel with delayed csit"
    - "optimal use of current and outdated channel state information degrees of freedom of the miso bc with mixed csit"
    - "interference alignment for the mimo interference channel with delayed local csit"
    - "secrecy degrees of freedom of mimo broadcast channels with delayed csit"
    - "completely stale transmitter channel state information is still very useful"

Connected through hyperedge HE-8 (induced by source paper "secrecy analysis on network coding in bidirectional multibeam satellite communications"):
  with members:
    - "a secure communication game with a relay helping the eavesdropper"
    - "interference alignment for secrecy"
    - "joint relay and jammer selection for secure two way relay networks"
    - "secure satellite communication systems design with individual secrecy rate constraints"
    - "physical layer security combining error control coding and cryptography"

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)