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: "cobalt bft governance in open networks"
  Abstract: We present Cobalt, a novel atomic broadcast algorithm that works in networks with non-uniform trust and no global agreement on participants, and is probabilistically guaranteed to make forward progress even in the presence of maximal faults and arbitrary asynchrony. The exact properties that Cobalt satisfies makes it particularly applicable to designing an efficient decentralized "voting network" that allows a public, open-entry group of nodes to agree on changes to some shared set of rules in a fair and consistent manner while tolerating some trusted nodes and arbitrarily many untrusted nodes behaving maliciously. We also define a new set of properties which must be satisfied by any safe decentralized governance algorithm, and all of which Cobalt satisfies.

Connected through hyperedge HE-1 (induced by source paper "two more algorithms for randomized signature free asynchronous binary byzantine consensus with t n 3 and o n 2 messages and o 1 round expected termination"):
  with members:
    - "a simple and efficient binary byzantine consensus algorithm using cryptography and partial synchrony"
    - "a simple and efficient asynchronous randomized binary byzantine consensus algorithm"
    - "xft practical fault tolerance beyond crashes"
    - "randomized protocols for asynchronous consensus"

Connected through hyperedge HE-2 (induced by source paper "decentralization in open quorum systems"):
  with members:
    - "complexity of the quorum intersection property of the federated byzantine agreement system"
    - "is stellar as secure as you think"
    - "analysis of the xrp ledger consensus protocol"
    - "blockchains consensus protocols in the wild"
    - "a tutorial on modeling and analysis of dynamic social networks part i"
    - "majority is not enough bitcoin mining is vulnerable"

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)