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 blockchain based flight data recorder for cloud accountability"
  Abstract: Many companies rely on Cloud infrastructures for their computation, communication and data storage requirements. While Cloud services provide some benefits, e.g., replacing high upfront costs for an IT infrastructure with a pay-as-you-go model, they also introduce serious concerns that are notoriously difficult to address. In essence, Cloud customers are storing data and running computations on infrastructures that they can not control directly. Therefore, when problems arise -- violations of Service Level Agreements, data corruption, data leakage, security breaches -- both customers and Cloud providers face the challenge of agreeing on which party is to be held responsible. In this paper, we review the challenges and requirements for enforcing accountability in Cloud infrastructures, and argue that smart contracts and blockchain technologies might provide a key contribution towards accountable Clouds.

Connected through hyperedge HE-1 (induced by source paper "are distributed ledger technologies ready for smart transportation systems"):
  with members:
    - "likestarter a smart contract based social dao for crowdfunding"
    - "a distributed ledger based infrastructure for smart transportation system and social good"
    - "on the ethereum blockchain structure a complex networks theory perspective"
    - "orchestrating product provenance story when iota ecosystem meets the electronics supply chain space"
    - "iota feasibility and perspectives for enabling vehicular applications"
    - "blackchain scalability for resource constrained accountable vehicle to x communication"
    - "multi level simulation of internet of things on smart territories"
    - "simulation of the internet of things"

Connected through hyperedge HE-2 (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"
    - "a survey of distributed consensus protocols for blockchain networks"
    - "decentralization in bitcoin and ethereum networks"
    - "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-3 (induced by source paper "on the ethereum blockchain structure a complex networks theory perspective"):
  with members:
    - "likestarter a smart contract based social dao for crowdfunding"
    - "towards blockchain enabled wireless mesh networks"
    - "towards blockchain based auditable storage and sharing of iot data"
    - "smart contract slas for dense small cell as a service"
    - "a blockchain based approach for data accountability and provenance tracking"
    - "highly intensive data dissemination in complex networks"
    - "simulation of the internet of things"

Connected through hyperedge HE-4 (induced by source paper "a distributed ledger based infrastructure for smart transportation system and social good"):
  with members:
    - "likestarter a smart contract based social dao for crowdfunding"
    - "on the ethereum blockchain structure a complex networks theory perspective"
    - "idmob iot data marketplace on blockchain"
    - "towards blockchain based auditable storage and sharing of iot data"
    - "ipfs content addressed versioned p2p file system"

Connected through hyperedge HE-5 (induced by source paper "likestarter a smart contract based social dao for crowdfunding"):
  with members:
    - "the ico phenomenon and its relationships with ethereum smart contract environment"
    - "decentralized applications the blockchain empowered software system"
    - "highly intensive data dissemination in complex networks"

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.DC(Distributed, Parallel, and Cluster Computing)