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: "a survey of distributed consensus protocols for blockchain networks"
  Abstract: Since the inception of Bitcoin, cryptocurrencies and the underlying blockchain technology have attracted an increasing interest from both academia and industry. Among various core components, consensus protocol is the defining technology behind the security and performance of blockchain. From incremental modifications of Nakamoto consensus protocol to innovative alternative consensus mechanisms, many consensus protocols have been proposed to improve the performance of the blockchain network itself or to accommodate other specific application needs. #R##N#In this survey, we present a comprehensive review and analysis on the state-of-the-art blockchain consensus protocols. To facilitate the discussion of our analysis, we first introduce the key definitions and relevant results in the classic theory of fault tolerance which helps to lay the foundation for further discussion. We identify five core components in a blockchain, namely, block proposal, block validation, information propagation, block finalization, and incentive mechanism. A wide spectrum of blockchain consensus protocols are then carefully reviewed accompanied by algorithmic abstractions and vulnerability analyses. The surveyed consensus protocols are analyzed using the five-component framework and compared with respect to different performance metrics. These analyses and comparisons provide us new insights in the fundamental differences of various proposals in terms of their suitable application scenarios, key assumptions, expected fault tolerance, scalability, drawbacks and trade-offs. We believe this survey will provide blockchain developers and researchers a comprehensive view on the state-of-the-art consensus protocols and facilitate the process of designing future protocols.

Connected through hyperedge HE-1 (induced by source paper "modeling the impact of network connectivity on consensus security of proof of work blockchain"):
  with members:
    - "decentralization in bitcoin and ethereum networks"
    - "consensus in the age of blockchains"
    - "optimal selfish mining strategies in bitcoin"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-2 (induced by source paper "the security reference architecture for blockchains towards a standardized model for studying vulnerabilities threats and defenses"):
  with members:
    - "ekiden a platform for confidentiality preserving trustworthy and performant smart contracts"
    - "a survey on ethereum systems security vulnerabilities attacks and defenses"
    - "security and privacy on blockchain"
    - "deconstructing blockchains a comprehensive survey on consensus membership and structure"
    - "truffle tests for free replaying ethereum smart contracts for transparency"
    - "blockchain technologies for the internet of things research issues and challenges"
    - "exploring the attack surface of blockchain a systematic overview"
    - "strongchain transparent and collaborative proof of work consensus"

Connected through hyperedge HE-3 (induced by source paper "a survey on ethereum systems security vulnerabilities attacks and defenses"):
  with members:
    - "security and privacy on blockchain"
    - "exploring the attack surface of blockchain a systematic overview"
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "metrics towards measuring cyber agility"
    - "selfish mining in ethereum"
    - "finding the greedy prodigal and suicidal contracts at scale"
    - "ethir a framework for high level analysis of ethereum bytecode"
    - "online detection of effectively callback free objects with applications to smart contracts"

Connected through hyperedge HE-4 (induced by source paper "microchain a light hierarchical consensus protocol for iot system"):
  with members:
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "decentralized smart surveillance through microservices platform"
    - "a survey on applications of game theory in blockchain"
    - "blockchain methods for trusted avionics systems"
    - "blendmas a blockchain enabled decentralized microservices architecture for smart public safety"
    - "microchain a hybrid consensus mechanism for lightweight distributed ledger for iot"
    - "blendcac a blockchain enabled decentralized capability based access control for iots"
    - "a microservice enabled architecture for smart surveillance using blockchain technology"

Connected through hyperedge HE-5 (induced by source paper "agent based simulation of blockchains"):
  with members:
    - "simblock a blockchain network simulator"
    - "likestarter a smart contract based social dao for crowdfunding"
    - "decentralization in bitcoin and ethereum networks"
    - "a blockchain based flight data recorder for cloud accountability"
    - "highly intensive data dissemination in complex networks"
    - "the simulation model partitioning problem an adaptive solution based on self clustering"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-6 (induced by source paper "permissioned blockchain for efficient and secure resource sharing in vehicular edge computing"):
  with members:
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "hyperledger fabric a distributed operating system for permissioned blockchains"
    - "end to end performance analysis of relay cooperative communication based on parked cars"
    - "blockchain a distributed solution to automotive security and privacy"
    - "offloading in software defined network at edge with information asymmetry a contract theoretical approach"

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)