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: "certificate transparency with privacy"
  Abstract: Certificate transparency (CT) is an elegant mechanism designed to detect when a certificate authority (CA) has issued a certificate incorrectly. Many CAs now support CT and it is being actively deployed in browsers. However, a number of privacy-related challenges remain. In this paper we propose practical solutions to two issues. First, we develop a mechanism that enables web browsers to audit a CT log without violating user privacy. Second, we extend CT to support non-public subdomains.

Connected through hyperedge HE-1 (induced by source paper "improving pki bgp and dns using blockchain a systematic review"):
  with members:
    - "lightchain a dht based blockchain for resource constrained environments"
    - "certledger a new pki model with certificate transparency based on blockchain"
    - "hyperledger fabric a distributed operating system for permissioned blockchains"
    - "certificate transparency with privacy"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-2 (induced by source paper "characterizing the root landscape of certificate transparency logs"):
  with members:
    - "the rise of certificate transparency and its implications on the internet ecosystem"
    - "certificate transparency with privacy"

Connected through hyperedge HE-3 (induced by source paper "contour a practical system for binary transparency"):
  with members:
    - "an analysis of bitcoin op_return metadata"
    - "certificate transparency with privacy"
    - "enhancing bitcoin security and performance with strong consistency via collective signing"
    - "keeping authorities honest or bust with decentralized witness cosigning"
    - "efficient gossip protocols for verifying the consistency of certificate logs"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-4 (induced by source paper "multiparty routing secure routing for mixnets"):
  with members:
    - "certificate transparency with privacy"
    - "atom horizontally scaling strong anonymity"
    - "anonymous card shuffling and its applications to parallel mixnets"

Connected through hyperedge HE-5 (induced by source paper "hiding in plain sight a longitudinal study of combosquatting abuse"):
  with members:
    - "dial one for scam a large scale analysis of technical support scams"
    - "certificate transparency with privacy"

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)