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: "network and security analysis of anonymous communication networks"
  Abstract: Anonymous communication networks are popular for providing a means of covert communication and secure exchange of data. Analysis of such networks is challenging due to the high degree of anonymity and unconventional ways to access these networks. In this paper, we use network analysis as a tool to analyze the structure of these networks and assess the privacy and security provided by these networks. We study two popular anonymous communication networks, TOR and Freenet, by analyzing a large number of nodes and compare them on the basis of different network metrics. We differentiate between Mixnet and Peer-to-Peer(P2P) anonymous networks based on the results of the structural analysis. Our study confirms power law assumptions and displays the small world characteristics of anonymous communication networks. Our study suggests that TOR has a sparse structure with a well-connected core while Freenet is a compact and a highly connected network. We look at the security and privacy implications of our results and note the differences and similarities between the two networks. Based on random network attacks on both the networks we conclude that Freenet(P2P) is more robust and secure to network attacks than TOR(Mixnet).

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)