human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "securing massive mimo at the physical layer"):
  Abstract: We consider a single-cell downlink massive MIMO system in the presence of attackers capable of jamming and eavesdropping. We show that, classical attacks of data jamming and eavesdropping can be simultaneously rendered useless. Specifically, we show that, without the need to use wiretap encoding, users achieve secure and reliable communication rate of which increases at the same speed as the rate achieved under no attack as the number of antennas grow. However, we introduce a new attack strategy that involves jamming pilot signals and eavesdropping in succession and show significant reductions in the achievable secrecy rate, even in the asymptotic regime in number of antennas. We develop counter strategies for this new attack in which we use secret key to encrypt the pilot sequence, rather than the data. We show that hiding the training signal assignments from the attacker enables the mobiles to achieve a secure degrees of freedom, identical to the one achieved under no attack.

Includes members:
  Member "blind pilot decontamination":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "on the pilot contamination attack in multi cell multiuser massive mimo networks")
  Member "energy and spectral efficiency of very large multiuser mimo systems":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "downlink secrecy rate of one bit massive mimo system with active eavesdropping")
  Member "secure transmission with multiple antennas ii the mimome wiretap channel":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "multi antenna jamming in covert communication")
  Member "pilot contamination and precoding in multi cell tdd systems":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "downlink secrecy rate of one bit massive mimo system with active eavesdropping")
  Member "the secrecy capacity of the mimo wiretap channel":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "angle aware user cooperation for secure massive mimo in rician fading channel")

Question: Please tell me which class the source paper 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)