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: "mosquito covert ultrasonic transmissions between two air gapped computers using speaker to speaker communication"
  Abstract: In this paper we show how two (or more) airgapped computers in the same room, equipped with passive speakers, headphones, or earphones can covertly exchange data via ultrasonic waves. Microphones are not required. Our method is based on the capability of a malware to exploit a specific audio chip feature in order to reverse the connected speakers from output devices into input devices - unobtrusively rendering them microphones. We discuss the attack model and provide technical background and implementation details. We show that although the reversed speakers/headphones/earphones were not originally designed to perform as microphones, they still respond well to the near-ultrasonic range (18kHz to 24kHz). We evaluate the communication channel with different equipment, and at various distances and transmission speeds, and also discuss some practical considerations. Our results show that the speaker-to-speaker communication can be used to covertly transmit data between two air-gapped computers positioned a maximum of nine meters away from one another. Moreover, we show that two (microphone-less) headphones can exchange data from a distance of three meters apart. This enables 'headphones-to-headphones' covert communication, which is discussed for the first time in this paper.

Connected through hyperedge HE-1 (induced by source paper "powerhammer exfiltrating data from air gapped computers through power lines"):
  with members:
    - "data exfiltration via multipurpose rfid cards and countermeasures"
    - "optical exfiltration of data via keyboard led status indicators to ip cameras"
    - "optical tempest"
    - "odini escaping sensitive data from faraday caged air gapped computers via magnetic fields"
    - "magneto covert channel between air gapped systems and nearby smartphones via cpu generated magnetic fields"
    - "air jumper covert air gap exfiltration infiltration via security cameras infrared ir"
    - "xled covert data exfiltration from air gapped networks via router leds"
    - "usbee air gap covert channel via electromagnetic emission from usb"

Connected through hyperedge HE-2 (induced by source paper "beatcoin leaking private keys from air gapped cryptocurrency wallets"):
  with members:
    - "spectre attacks exploiting speculative execution"
    - "powerhammer exfiltrating data from air gapped computers through power lines"
    - "odini escaping sensitive data from faraday caged air gapped computers via magnetic fields"
    - "magneto covert channel between air gapped systems and nearby smartphones via cpu generated magnetic fields"
    - "air jumper covert air gap exfiltration infiltration via security cameras infrared ir"
    - "xled covert data exfiltration from air gapped networks via router leds"
    - "usbee air gap covert channel via electromagnetic emission from usb"
    - "fansmitter acoustic data exfiltration from speakerless air gapped computers"

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.CR(Cryptography and Security)