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: "encrypt flip flop a novel logic encryption technique for sequential circuits"
  Abstract: Logic Encryption is one of the most popular hardware security techniques which can prevent IP piracy and illegal IC overproduction. It introduces obfuscation by inserting some extra hardware into a design to hide its functionality from unauthorized users. Correct functionality of an encrypted design depends upon the application of correct keys, shared only with the authorized users. In the recent past, extensive efforts have been devoted in extracting the secret key of an encrypted design. At the same time, several countermeasures have also been proposed by the research community to thwart different state-of-the-art attacks on logic encryption. However, most of the proposed countermeasures fail to prevent the powerful SAT attack. Although a few researchers have proposed different solutions to withstand SAT attack, those solutions suffer from several drawbacks such as high design overheads, low output corruptibility, and vulnerability against removal attack. Almost all the known logic encryption strategies are vulnerable to scan based attack. In this paper, we propose a novel encryption technique called Encrypt Flip-Flop, which encrypts the outputs of selected flip-flops by inserting multiplexers (MUX). The proposed strategy can thwart all the known attacks including SAT and scan based attacks. The scheme has low design overhead and implementation complexity. Experimental results on several ISCAS'89 and ITC'99 benchmarks show that our proposed method can produce reasonable output corruption for wrong keys.

Connected through hyperedge HE-1 (induced by source paper "dfssd deep faults and shallow state duality a provably strong obfuscation solution for circuits with restricted access to scan chain"):
  with members:
    - "sat hard cyclic logic obfuscation for protecting the ip in the manufacturing supply chain"
    - "functional analysis attacks on logic locking"
    - "is robust design for security robust enough attack on locked circuits with restricted scan chain access"
    - "coma communication and obfuscation management architecture"
    - "threats on logic locking a decade later"
    - "benchmarking the capabilities and limitations of sat solvers in defeating obfuscation schemes"
    - "lut lock a novel lut based logic obfuscation for fpga bitstream and asic hardware protection"

Connected through hyperedge HE-2 (induced by source paper "is robust design for security robust enough attack on locked circuits with restricted scan chain access"):
  with members:
    - "functional analysis attacks on logic locking"

Connected through hyperedge HE-3 (induced by source paper "scansat unlocking static and dynamic scan obfuscation"):
  with members:
    - "functional analysis attacks on logic locking"

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)