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: "towards practical oblivious ram"
  Abstract: We take an important step forward in making Oblivious RAM (O-RAM) practical. We propose an O-RAM construction achieving an amortized overhead of 20X-35X (for an O-RAM roughly 1 terabyte in size), about 63 times faster than the best existing scheme. On the theoretic front, we propose a fundamentally novel technique for constructing Oblivious RAMs: specifically, we partition a bigger O-RAM into smaller O-RAMs, and employ a background eviction technique to obliviously evict blocks from the client-side cache into a randomly assigned server-side partition. This novel technique is the key to achieving the gains in practical performance.

Connected through hyperedge HE-1 (induced by source paper "dynamic skyline queries on encrypted data using result materialization"):
  with members:
    - "secure and efficient skyline queries on encrypted data"
    - "secure k nearest neighbor query over encrypted data in outsourced environments"

Connected through hyperedge HE-2 (induced by source paper "a double edged sword security threats and opportunities in one sided network communication"):
  with members:
    - "obladi oblivious serializable transactions in the cloud"
    - "the end of a myth distributed transactions can scale"
    - "rowhammer js a remote software induced fault attack in javascript"
    - "privacy preserving group data access via stateless oblivious ram simulation"
    - "privacy preserving access of outsourced data via oblivious ram simulation"

Connected through hyperedge HE-3 (induced by source paper "an algorithmic framework for differentially private data analysis on trusted processors"):
  with members:
    - "the privacy blanket of the shuffle model"
    - "amplification by shuffling from local to central differential privacy via anonymity"
    - "distributed differential privacy via shuffling"
    - "practical locally private heavy hitters"
    - "cachezoom how sgx amplifies the power of cache attacks"
    - "software grand exposure sgx cache attacks are practical"
    - "towards practical differential privacy for sql queries"
    - "prochlo strong privacy for analytics in the crowd"

Connected through hyperedge HE-4 (induced by source paper "location privacy in cognitive radio networks a survey"):
  with members:
    - "preserving the location privacy of secondary users in cooperative spectrum sensing"
    - "an efficient technique for protecting location privacy of cooperative spectrum sensing users"
    - "securefind secure and privacy preserving object finding via mobile crowdsourcing"
    - "lpos location privacy for optimal sensing in cognitive radio networks"
    - "geo indistinguishability differential privacy for location based systems"
    - "security of spectrum learning in cognitive radios"
    - "channel assignment with access contention resolution for cognitive radio networks"
    - "multi agent q learning of channel selection in multi user cognitive radio systems a two by two case"

Connected through hyperedge HE-5 (induced by source paper "mix oram using delegate shuffles"):
  with members:
    - "differentially private oblivious ram"
    - "zig zag sort a simple deterministic data oblivious sorting algorithm running in o n log n time"
    - "anonymous card shuffling and its applications to parallel mixnets"
    - "privacy preserving group data access via stateless oblivious ram simulation"
    - "randomized shellsort a simple oblivious sorting algorithm"

Connected through hyperedge HE-6 (induced by source paper "accessing data while preserving privacy"):
  with members:
    - "simultaneous private learning of multiple concepts"
    - "calibrating data to sensitivity in private data analysis"
    - "a learning theory approach to non interactive database privacy"

Connected through hyperedge HE-7 (induced by source paper "sope a spatial order preserving encryption model for multi dimensional data"):
  with members:
    - "a survey of skyline query processing"
    - "a survey on cloud security issues and techniques"
    - "privacy preserving access of outsourced data via oblivious ram simulation"

Connected through hyperedge HE-8 (induced by source paper "revisiting definitional foundations of oblivious ram for secure processor implementations"):
  with members:
    - "flat oram a simplified write only oblivious ram construction for secure processors"
    - "oblivious ram simulation with efficient worst case access overhead"
    - "privacy preserving group data access via stateless oblivious ram simulation"

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)