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: "intel sgx enabled key manager service with openstack barbican"
  Abstract: Protecting data in the cloud continues to gain in importance, with encryption being used to achieve the desired data protection. While there is desire to use encryption, various cloud components do not want to deal with key management, which points to a strong need for a separate key management system. OpenStack Barbican is a platform developed by the OpenStack community aimed at providing cryptographic functions useful for all environments, including large ephemeral clouds. Barbican exposes REST APIs designed for the secure storage, provisioning and management of secrets such as passwords, encryption keys, and X.509 certificates, and supports plugins for a variety of crypto solutions in the backend. Crypto plugins store secrets as encrypted blobs within the Barbican database. Software based crypto plugins offer a scalable solution, but are vulnerable to system software attacks. Hardware Security Module or HSM plugins offer strong security guarantees, but they are expensive and don't scale well. We propose to build an Intel Software Guard Extension or SGX based software crypto plugin that offers security similar to an HSM with the low cost and scalability of a software based solution. We extend OpenStack Barbican API to support attestation of an Intel SGX crypto plugin, to allow clients higher confidence in the software they are using for storing keys. In addition, the API provides support for mutual attestation for Intel SGX enabled clients, multi-user key distribution, and extensions for protecting the confidentiality and integrity of the backend database.

Connected through hyperedge HE-1 (induced by source paper "distributed systems and trusted execution environments trade offs and challenges"):
  with members:
    - "supply chain malware targets sgx take care of what you sign"
    - "anonymous and confidential file sharing over untrusted clouds"
    - "sgx lkl securing the host os interface for trusted execution"
    - "smotherspectre exploiting speculative execution through port contention"
    - "streambox tz secure stream analytics at the edge with trustzone"
    - "sgxpectre stealing intel secrets from sgx enclaves via speculative execution"
    - "cyclosa decentralizing private web search through sgx based browser extensions"
    - "ibbe sgx cryptographic group access control using trusted execution environments"

Connected through hyperedge HE-2 (induced by source paper "keys in the clouds auditable multi device access to cryptographic credentials"):
  with members:
    - "safekeeper protecting web passwords using trusted execution environments"
    - "the circle game scalable private membership test using trusted hardware"
    - "inferring fine grained control flow inside sgx enclaves with branch shadowing"

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)