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: "keystone an open framework for architecting tees"
  Abstract: Trusted execution environments (TEEs) are being used in all the devices from embedded sensors to cloud servers and encompass a range of cost, power constraints, and security threat model choices. On the other hand, each of the current vendor-specific TEEs makes a fixed set of trade-offs with little room for customization. We present Keystone -- the first open-source framework for building customized TEEs. Keystone uses simple abstractions provided by the hardware such as memory isolation and a programmable layer underneath untrusted components (e.g., OS). We build reusable TEE core primitives from these abstractions while allowing platform-specific modifications and application features. We showcase how Keystone-based TEEs run on unmodified RISC-V hardware and demonstrate the strengths of our design in terms of security, TCB size, execution of a range of benchmarks, applications, kernels, and deployment models.

Connected through hyperedge HE-1 (induced by source paper "on the convergence of artificial intelligence and distributed ledger technology a scoping review and future research agenda"):
  with members:
    - "ekiden a platform for confidentiality preserving trustworthy and performant smart contracts"
    - "energy recycling blockchain with proof of deep learning"
    - "decentralized and collaborative ai on blockchain"
    - "sok transparent dishonesty front running attacks on blockchain"
    - "reliable federated learning for mobile networks"
    - "tensorscone a secure tensorflow framework using intel sgx"
    - "coin ai a proof of useful work scheme for blockchain based distributed deep learning"
    - "mobile edge computing blockchain and reputation based crowdsourcing iot federated learning a secure decentralized and privacy preserving system"

Connected through hyperedge HE-2 (induced by source paper "sgx lkl securing the host os interface for trusted execution"):
  with members:
    - "dr sgx automated and adjustable side channel protection for sgx using data location randomization"
    - "zombieload cross privilege boundary data sampling"
    - "interface based side channel attack against intel sgx"
    - "obladi oblivious serializable transactions in the cloud"
    - "cachezoom how sgx amplifies the power of cache attacks"
    - "oblidb oblivious query processing for secure databases"
    - "software grand exposure sgx cache attacks are practical"
    - "prochlo strong privacy for analytics in the crowd"

Connected through hyperedge HE-3 (induced by source paper "an off chip attack on hardware enclaves via the memory bus"):
  with members:
    - "zombieload cross privilege boundary data sampling"
    - "cachezoom how sgx amplifies the power of cache attacks"
    - "software grand exposure sgx cache attacks are practical"
    - "rollback and forking detection for trusted execution environments using lightweight collective memory"
    - "malware guard extension using sgx to conceal cache attacks"
    - "inferring fine grained control flow inside sgx enclaves with branch shadowing"
    - "proof of luck an efficient blockchain consensus protocol"
    - "flush flush a fast and stealthy cache attack"

Connected through hyperedge HE-4 (induced by source paper "hyperservice interoperability and programmability across heterogeneous blockchains"):
  with members:
    - "ekiden a platform for confidentiality preserving trustworthy and performant smart contracts"
    - "concurrency and privacy with payment channel networks"
    - "atomic cross chain swaps"
    - "saql a stream based query system for real time abnormal system behavior detection"
    - "aiql enabling efficient attack investigation from system monitoring data"
    - "chainspace a sharded smart contracts platform"
    - "a concurrent perspective on smart contracts"
    - "enhancing bitcoin security and performance with strong consistency via collective signing"

Connected through hyperedge HE-5 (induced by source paper "substra a framework for privacy preserving traceable and collaborative machine learning"):
  with members:
    - "towards federated learning at scale system design"
    - "hyperledger fabric a distributed operating system for permissioned blockchains"
    - "sok security and privacy in machine learning"
    - "privacy risk in machine learning analyzing the connection to overfitting"
    - "stealing machine learning models via prediction apis"
    - "communication efficient learning of deep networks from decentralized data"
    - "deep residual learning for image recognition"

Connected through hyperedge HE-6 (induced by source paper "self expiring data capsule using trusted execution environment"):
  with members:
    - "autonomous membership service for enclave applications"
    - "towards scaling blockchain systems via sharding"
    - "rollback and forking detection for trusted execution environments using lightweight collective memory"

Connected through hyperedge HE-7 (induced by source paper "besfs a posix filesystem for enclaves with a mechanized safety proof"):
  with members:
    - "privado practical and secure dnn inference with enclaves"

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)