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: "censors delay in blocking circumvention proxies"
  Abstract: Censors of the Internet must continually discover and block new circumvention proxy servers. We seek to understand this process; specifically, the length of the delay between when a proxy first becomes discoverable and when it is actually blocked. We measure this delay in the case of obfuscated Tor bridges, by testing their reachability before and after their introduction into Tor Browser. We test from sites in the U.S., China, and Iran, over a period of five months. China's national firewall blocked new bridges after a varying delay of between 2 and 36 days. Blocking occurred only after end-user software releases, despite bridges being potentially discoverable earlier through other channels. While the firewall eventually discovered the bridges of Tor Browser, those that appeared only in Orbot, a version of Tor for mobile devices, remained unblocked. Our findings highlight the fact that censors can behave in ways that defy intuition, presenting difficulties for threat modeling but also opportunities for evasion.

Connected through hyperedge HE-1 (induced by source paper "an empirical study of the i2p anonymity network and its censorship resistance"):
  with members:
    - "torbricks blocking resistant tor bridge distribution"
    - "raptor routing attacks on privacy in tor"
    - "content and popularity analysis of tor hidden services"

Connected through hyperedge HE-2 (induced by source paper "a churn for the better localizing censorship using network level path churn and network tomography"):
  with members:
    - "exploring the design space of longitudinal censorship measurement platforms"
    - "raptor routing attacks on privacy in tor"
    - "network capability in localizing node failures via end to end path measurements"
    - "the anatomy of web censorship in pakistan"

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)