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: "an energy efficient reconfigurable dtls cryptographic engine for securing internet of things applications"
  Abstract: This paper presents the first hardware implementation of the datagram transport layer security (DTLS) protocol to enable end-to-end security for the Internet of Things (IoT). A key component of this design is a reconfigurable prime field elliptic curve cryptography (ECC) accelerator that is 238   $\times $    and 9   $\times $    more energy-efficient compared to software and state-of-the-art hardware, respectively. Our full hardware implementation of the DTLS 1.3 protocol provides 438   $\times $    improvement in energy-efficiency over software, along with code size and data memory usage as low as 8 and 3 KB, respectively. The cryptographic accelerators are coupled with an on-chip low-power RISC-V processor to benchmark applications beyond DTLS with up to two orders of magnitude energy savings. The test chip, fabricated in 65-nm CMOS, demonstrates hardware-accelerated DTLS sessions while consuming 44.08    $\mu \text{J}$   /handshake and 0.89 nJ/byte of the encrypted data at 16 MHz and 0.8 V.

Connected through hyperedge HE-1 (induced by source paper "effective scaling of blockchain beyond consensus innovations and moore s law"):
  with members:
    - "concurrency and privacy with payment channel networks"
    - "scalable byzantine consensus via hardware assisted secret sharing"
    - "blockchain goes green an analysis of blockchain on low power nodes"
    - "morph an adaptive framework for efficient and byzantine fault tolerant sdn control plane"
    - "towards scaling blockchain systems via sharding"
    - "a scale out blockchain for value transfer with spontaneous sharding"
    - "scaling nakamoto consensus to thousands of transactions per second"
    - "blockbench a framework for analyzing private blockchains"

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)