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: "new results on multiple input multiple output broadcast channels with confidential messages"
  Abstract: This paper presents two new results on multiple-input multiple-output (MIMO) Gaussian broadcast channels with confidential messages. First, the MIMO Gaussian wiretap channel is revisited. A matrix characterization of the capacity-equivocation region is provided, which extends the previous result on the secrecy capacity to the more general imperfect secrecy setting. Next, the MIMO Gaussian broadcast channel with two receivers and three independent messages: a common message intended for both receivers, and two confidential messages each intended for one of the receivers but needing to be kept asymptotically perfectly secret from the other, is considered. A precise characterization of the capacity region is provided, generalizing the previous results which considered only two out of three possible messages.

Connected through hyperedge HE-1 (induced by source paper "vector gaussian successive refinement with degraded side information"):
  with members:
    - "the sum rate of vector gaussian multiple description coding with tree structured covariance distortion constraints"
    - "vector gaussian rate distortion with variable side information"
    - "broadcasting correlated vector gaussians"
    - "private broadcasting over independent parallel channels"
    - "information theoretic proofs of entropy power inequalities"
    - "secure lossy transmission of vector gaussian sources"
    - "capacity equivocation region of the gaussian mimo wiretap channel"
    - "capacity region of gaussian mimo broadcast channels with common and confidential messages"

Connected through hyperedge HE-2 (induced by source paper "secure broadcasting using independent secret keys"):
  with members:
    - "secrecy results for compound wiretap channels"
    - "strong secrecy for multiple access channels"
    - "effective secrecy reliability confusion and stealth"
    - "capacity results for compound wiretap channels"
    - "strong secrecy from channel resolvability"
    - "capacity region of gaussian mimo broadcast channels with common and confidential messages"
    - "discrete memoryless interference and broadcast channels with confidential messages secrecy rate regions"
    - "secret communication with feedback"

Connected through hyperedge HE-3 (induced by source paper "physical layer service integration in 5g potentials and challenges"):
  with members:
    - "fundamental green tradeoffs progresses challenges and impacts on 5g networks"
    - "an overview of sustainable green 5g networks"
    - "gsvd based precoding in mimo systems with integrated services"
    - "robust artificial noise aided transmit design for multi user miso systems with integrated services"
    - "wireless powered communication opportunities and challenges"
    - "multi antenna relay aided wireless physical layer security"
    - "enhancing wireless information and power transfer by exploiting multi antenna techniques"
    - "simultaneous wireless information and power transfer in modern communication systems"

Connected through hyperedge HE-4 (induced by source paper "artificial noise aided biobjective transmitter optimization for service integration in multi user mimo broadcast channel"):
  with members:
    - "gsvd based precoding in mimo systems with integrated services"
    - "robust artificial noise aided transmit design for multi user miso systems with integrated services"
    - "what will 5g be"
    - "principles of physical layer security in multiuser wireless networks a survey"
    - "physical layer multicasting by stochastic transmit beamforming and alamouti space time coding"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"
    - "wireless physical layer security with imperfect channel state information a survey"
    - "precoder design for physical layer multicasting"

Connected through hyperedge HE-5 (induced by source paper "robust artificial noise aided transmit design for multi user miso systems with integrated services"):
  with members:
    - "safeguarding decentralized wireless networks using full duplex jamming receivers"
    - "principles of physical layer security in multiuser wireless networks a survey"
    - "physical layer multicasting by stochastic transmit beamforming and alamouti space time coding"
    - "wireless physical layer security with imperfect channel state information a survey"
    - "outage constrained robust secure transmission for miso wiretap channels"
    - "precoder design for physical layer multicasting"
    - "robust secure transmission in miso channels based on worst case optimization"
    - "optimal and robust transmit designs for miso channel secrecy by semidefinite programming"

Connected through hyperedge HE-6 (induced by source paper "individual secrecy for broadcast channels with receiver side information"):
  with members:
    - "secure multiplex coding with dependent and non uniform multiple messages"
    - "strong secrecy for cooperative broadcast channels"
    - "individual secrecy for the broadcast channel"
    - "secrecy capacity region of some classes of wiretap broadcast channels"
    - "capacity regions for broadcast channels with degraded message sets and message cognition under different secrecy constraints"
    - "on block security of regenerating codes at the mbr point for distributed storage systems"
    - "effective secrecy reliability confusion and stealth"
    - "reliability and secrecy functions of the wiretap channel under cost constraint"

Connected through hyperedge HE-7 (induced by source paper "secure degrees of freedom of multi user networks one time pads in the air via alignment"):
  with members:
    - "secure degrees of freedom of one hop wireless networks"
    - "real interference alignment exploiting the potential of single antenna systems"
    - "secure degrees of freedom of the gaussian wiretap channel with helpers and no eavesdropper csi blind cooperative jamming"
    - "interference alignment for secrecy"
    - "strongly secure communications over the two way wiretap channel"
    - "on the secure degrees of freedom of the multiple access channel"
    - "ergodic secret alignment"
    - "cooperation with an untrusted relay a secrecy perspective"

Connected through hyperedge HE-8 (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"
    - "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"
    - "secure communication over parallel relay channel"
    - "interference alignment for the mimo interference channel with delayed local csit"

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)