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: "vive la difference paxos vs viewstamped replication vs zab"
  Abstract: Paxos, Viewstamped Replication, and Zab are replication protocols that ensure high-availability in asynchronous environments with crash failures. Various claims have been made about similarities and differences between these protocols. But how does one determine whether two protocols are the same, and if not, how significant the differences are? #R##N#We propose to address these questions using refinement mappings, where protocols are expressed as succinct specifications that are progressively refined to executable implementations. Doing so enables a principled understanding of the correctness of the different design decisions that went into implementing the various protocols. Additionally, it allowed us to identify key differences that have a significant impact on performance.

Connected through hyperedge HE-1 (induced by source paper "what s live understanding distributed consensus"):
  with members:
    - "moderately complex paxos made simple high level executable specification of distributed algorithms"
    - "paxos consensus deconstructed and abstracted extended version"
    - "paxos made epr decidable reasoning about distributed protocols"
    - "from clarity to efficiency for distributed algorithms"

Connected through hyperedge HE-2 (induced by source paper "can 100 machines agree"):
  with members:
    - "the consensus number of a cryptocurrency"
    - "sbft a scalable and decentralized trust infrastructure"
    - "hyperledger fabric a distributed operating system for permissioned blockchains"
    - "sbft a scalable decentralized trust infrastructure for blockchains"
    - "a byzantine fault tolerant ordering service for the hyperledger fabric blockchain platform"
    - "revisiting fast practical byzantine fault tolerance"
    - "enhancing bitcoin security and performance with strong consistency via collective signing"
    - "incremental consistency guarantees for replicated objects"

Connected through hyperedge HE-3 (induced by source paper "moderately complex paxos made simple high level executable specification of distributed algorithms"):
  with members:
    - "simpler specifications and easier proofs of distributed algorithms using history variables"
    - "paxos made epr decidable reasoning about distributed protocols"
    - "formal verification of multi paxos for distributed consensus"
    - "from clarity to efficiency for distributed algorithms"

Connected through hyperedge HE-4 (induced by source paper "on the parallels between paxos and raft and how to port optimizations"):
  with members:
    - "wpaxos wide area network flexible consensus"
    - "solida a blockchain protocol based on reconfigurable byzantine consensus"
    - "ht paxos high throughput state machine replication protocol for large clustered data centers"

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)