human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "building scalable decentralized payment systems"):
  Abstract: Increasing the transactional throughput of decentralized blockchains in a secure manner has been the holy grail of blockchain research for most of the past decade. This paper introduces a scheme for scaling blockchains while retaining virtually identical security and decentralization, and discusses requirements for deploying such a solution in practice. We propose a layer-2 scaling technique using a permissionless side chain with merged block production similar to merged mining. The side chain only supports functionality to transact UTXOs and transfer funds to and from a parent chain in a practically trustless manner. Optimized implementation and engineering of client code, along with improvements to block propagation efficiency versus currently deployed systems, allow this side chain to scale well beyond the capacities exhibited by contemporary blockchains. Finally, a discussion on navigating the complex political landscape of the present-day blockchain space is explored in order to develop compelling steps towards deploying such a side chain in real-world conditions.

Includes members:
  Member "a scalable verification solution for blockchains":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "on the convergence of artificial intelligence and distributed ledger technology a scoping review and future research agenda")
  Member "incentives in ethereum s hybrid casper protocol":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "presto a systematic framework for blockchain consensus protocols")
  Member "atomic cross chain swaps":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "throughput optimal routing in blockchain based payment systems")
  Member "consensus in the age of blockchains":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "hushrelay a privacy preserving efficient and scalable routing algorithm for off chain payments")
  Member "casper the friendly finality gadget":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "surface a practical blockchain consensus algorithm for real world networks")
  Member "invertible bloom lookup tables":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "peeling close to the orientability threshold spatial coupling in hashing based data structures")

Question: Please tell me which class the source paper 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)