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: "a survey on hardware based security mechanisms for internet of things"
  Abstract: The vast areas of applications for IoTs in future smart cities, industrial automation, smart transportation systems, and smart health facilities represent a thriving surface for several security attacks with enormous economic, environmental and societal impacts. This survey paper presents a review of several security challenges of emerging IoT networks and discusses some of the attacks and their countermeasures based on different domains in IoT networks. Most conventional security solutions for IoT networks are adopted from communication networks while noting the particular characteristics of IoT networks such as the huge number of nodes, heterogeneity of the network, and the limited energy, communication, and computation of the nodes, these conventional security methods are not really adequate. One important challenge toward utilizing common secret key-based cryptographic methods in very large scale IoT networks is the problem of secret key generation, distribution, and storage in IoT devices and more importantly protecting these secret keys from physical attacks. Physically unclonable functions (PUFs) are recently utilized as a promising hardware security solution for identification and authentication in IoT networks. Since PUFs extract the unique hardware characteristics, they potentially offer an affordable and practical solution for secret key generation. However, several barriers limit the applications of different types of PUFs for key generation purposes. We discuss the advantages of PUF-based key generation methods, review the state-of-the-art techniques in this field and propose a reliable PUF-based solution for secret key generation using resistive random-access memories (RERAMs) embedded in IoTs.

Connected through hyperedge HE-1 (induced by source paper "an autonomous spectrum management scheme for unmanned aerial vehicle networks in disaster relief operations"):
  with members:
    - "a solution for dynamic spectrum management in mission critical uav networks"
    - "ring oscillator and its application as physical unclonable function puf for password management"
    - "overview of blakley s secret sharing scheme"
    - "a reputation based stackelberg game model to enhance secrecy rate in spectrum leasing to selfish iot devices"
    - "leader follower based coalition formation in large scale uav networks a quantum evolutionary approach"
    - "traffic light control using deep policy gradient and value function based reinforcement learning"
    - "waveform and spectrum management for unmanned aerial systems beyond 2025"
    - "spectrum sharing and cyclical multiple access in uav aided cellular offloading"

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)