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: "on subversive miner strategies and block withholding attack in bitcoin digital currency"
  Abstract: Bitcoin is a "crypto currency", a decentralized electronic payment scheme based on cryptography. Bitcoin economy grows at an incredibly fast rate and is now worth some 10 billions of dollars. Bitcoin mining is an activity which consists of creating (minting) the new coins which are later put into circulation. Miners spend electricity on solving cryptographic puzzles and they are also gatekeepers which validate bitcoin transactions of other people. Miners are expected to be honest and have some incentives to behave well. However. In this paper we look at the miner strategies with particular attention paid to subversive and dishonest strategies or those which could put bitcoin and its reputation in danger. We study in details several recent attacks in which dishonest miners obtain a higher reward than their relative contribution to the network. In particular we revisit the concept of block withholding attacks and propose a new concrete and practical block withholding attack which we show to maximize the advantage gained by rogue miners. #R##N#RECENT EVENTS: it seems that the attack was recently executed, see Section XI-A.

Connected through hyperedge HE-1 (induced by source paper "exploring the attack surface of blockchain a systematic overview"):
  with members:
    - "scalable byzantine consensus via hardware assisted secret sharing"
    - "security services using blockchains a state of the art survey"
    - "a survey on the security of blockchain systems"
    - "an empirical analysis of anonymity in zcash"
    - "towards blockchain driven secure and transparent audit logs"
    - "end to end analysis of in browser cryptojacking"
    - "linbft linear communication byzantine fault tolerance for public blockchains"
    - "a survey on security and privacy issues of bitcoin"

Connected through hyperedge HE-2 (induced by source paper "a survey on applications of game theory in blockchain"):
  with members:
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "security services using blockchains a state of the art survey"
    - "blockchain governance game"
    - "exchange of renewable energy among prosumers using blockchain with dynamic pricing"
    - "game of coins"
    - "delayed blockchain protocols"
    - "reward sharing schemes for stake pools"
    - "a survey on the security of blockchain systems"

Connected through hyperedge HE-3 (induced by source paper "strongchain transparent and collaborative proof of work consensus"):
  with members:
    - "decentralization in bitcoin and ethereum networks"
    - "short paper towards more reliable bitcoin timestamps"
    - "the impact of uncle rewards on selfish mining in ethereum"
    - "the gap game"
    - "enhancing bitcoin security and performance with strong consistency via collective signing"
    - "optimal selfish mining strategies in bitcoin"
    - "bitcoin ng a scalable blockchain protocol"
    - "the miner s dilemma"

Connected through hyperedge HE-4 (induced by source paper "a deep dive into bitcoin mining pools an empirical analysis of mining shares"):
  with members:
    - "decentralization in bitcoin and ethereum networks"
    - "estimation of miner hash rates and consensus on blockchains draft"
    - "bitcoin s security model revisited"
    - "the unreasonable effectiveness of address clustering"
    - "optimal selfish mining strategies in bitcoin"
    - "analysis of hashrate based double spending"
    - "the miner s dilemma"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-5 (induced by source paper "competing semi selfish miners in bitcoin"):
  with members:
    - "blockchain mining games with pay forward"
    - "a deep dive into blockchain selfish mining"
    - "be selfish and avoid dilemmas fork after withholding faw attacks on bitcoin"
    - "blockchain mining games"
    - "optimal selfish mining strategies in bitcoin"
    - "bitcoin ng a scalable blockchain protocol"
    - "the miner s dilemma"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-6 (induced by source paper "hopping proof and fee free pooled mining in blockchain"):
  with members:
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "diversification across mining pools optimal mining strategies under pow"
    - "countering selfish mining in blockchains"
    - "evolutionary game for mining pool selection in blockchain networks"
    - "optimal selfish mining strategies in bitcoin"
    - "the miner s dilemma"
    - "majority is not enough bitcoin mining is vulnerable"
    - "analysis of bitcoin pooled mining reward systems"

Connected through hyperedge HE-7 (induced by source paper "blockchain mining games with pay forward"):
  with members:
    - "blockchain mining games"
    - "optimal selfish mining strategies in bitcoin"
    - "bitcoin ng a scalable blockchain protocol"
    - "analysis of hashrate based double spending"
    - "the miner s dilemma"
    - "majority is not enough bitcoin mining is vulnerable"
    - "on bitcoin and red balloons"
    - "analysis of bitcoin pooled mining reward systems"

Connected through hyperedge HE-8 (induced by source paper "an eye for an eye economics of retaliation in mining pools"):
  with members:
    - "bitcoin vs bitcoin cash coexistence or downfall of bitcoin cash"
    - "the gap game"
    - "be selfish and avoid dilemmas fork after withholding faw attacks on bitcoin"
    - "optimal selfish mining strategies in bitcoin"
    - "the miner s dilemma"
    - "majority is not enough bitcoin mining is vulnerable"
    - "analysis of bitcoin pooled mining reward systems"

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)