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: "managing nymboxes for identity and tracking protection"
  Abstract: Despite the attempts of well-designed anonymous communication tools to protect users from tracking or identification, flaws in surrounding software (such as web browsers) and mistakes in configuration may leak the user's identity. We introduce Nymix, an anonymity-centric operating system architecture designed "top-to-bottom" to strengthen identity- and tracking-protection. Nymix's core contribution is OS support for nym-browsing: independent, parallel, and ephemeral web sessions. Each web session, or pseudonym, runs in a unique virtual machine (VM) instance evolving from a common base state with support for long-lived sessions which can be anonymously stored to the cloud, avoiding de-anonymization despite potential confiscation or theft. Nymix allows a user to safely browse the Web using various different transports simultaneously through a pluggable communication model that supports Tor, Dissent, and a private browsing mode. In evaluations, Nymix consumes 600 MB per nymbox and loads within 15 to 25 seconds.

Connected through hyperedge HE-1 (induced by source paper "seeking anonymity in an internet panopticon"):
  with members:
    - "hang with your buddies to resist intersection attacks"
    - "proactively accountable anonymous messaging in verdict"
    - "probabilistic analysis of onion routing in a black box model"

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.OS(Operating Systems)