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: "lnbot a covert hybrid botnet on bitcoin lightning network"
  Abstract: While various covert Botnets were proposed in the past, they still lack complete anonymization for their servers/botmasters or suffer from slower communications among the botmaster and bots. In this paper, we propose LNBot, a new generation hybrid botnet that covertly communicates over Bitcoin Lightning Network (LN) which was recently introduced for faster Bitcoin transactions without writing on the blockchain. LNBot is a scalable two-layer botnet designed to completely anonymize the identity of the botmaster and its communication with multiple command and control (C&C) servers which maintain their own mini botnets by exploiting the various anonymity features of LN. Specifically, LNBot allows any type of commands to be sent instantly by the botmaster to the C&C servers which are ASCII or Huffman-encoded direct payments and forwarded via the LN payment infrastructure. These commands can then be further relayed to bots recruited by each C&C server. We implemented a proof-of-concept on the actual Bitcoin network and analyzed the delay and cost performance of the proposed approaches.

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)