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: "security of cyber physical systems"
  Abstract: Traditional control environments connected to physical systems are being upgraded with novel information and communication technologies. The resulting systems need to be adequately protected. Experimental testbeds are crucial for the study and analysis of ongoing threats against those resulting cyber-physical systems. The research presented in this paper discusses some actions towards the development of a replicable and affordable cyber-physical testbed for training and research. The architecture of the testbed is based on real-world components, and emulates cyber-physical scenarios commanded by SCADA (Supervisory Control And Data Acquisition) technologies. We focus on two representative protocols, Modbus and DNP3. The paper reports as well the development of some adversarial scenarios, in order to evaluate the testbed under cyber-physical threat situations. Some detection strategies are evaluated using our proposed testbed.

Connected through hyperedge HE-1 (induced by source paper "the effect of iot new features on security and privacy new threats existing solutions and challenges yet to be solved"):
  with members:
    - "trustshadow secure execution of unmodified applications with arm trustzone"
    - "from physical to cyber escalating protection for personalized auto insurance"

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)