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: "chaotic iterations versus spread spectrum chaos and stego security"
  Abstract: A new framework for information hiding security, called chaos-security, has been proposed in a previous study. It is based on the evaluation of unpredictability of the scheme, whereas existing notions of security, as stego-security, are more linked to information leaks. It has been proven that spread-spectrum techniques, a well-known stego-secure scheme, are chaos-secure too. In this paper, the links between the two notions of security is deepened and the usability of chaos-security is clarified, by presenting a novel data hiding scheme that is twice stego and chaos-secure. This last scheme has better scores than spread-spectrum when evaluating qualitative and quantitative chaos-security properties. Incidentally, this result shows that the new framework for security tends to improve the ability to compare data hiding scheme.

Connected through hyperedge HE-1 (induced by source paper "a cryptographic approach for steganography"):
  with members:
    - "a new chaos based watermarking algorithm"
    - "lyapunov exponent evaluation of a digital watermarking scheme proven to be secure"
    - "steganography a class of algorithms having secure properties"

Connected through hyperedge HE-2 (induced by source paper "low cost monitoring and intruders detection using wireless video sensor networks"):
  with members:
    - "hash functions using chaotic iterations"
    - "topological chaos and chaotic iterations application to hash functions"
    - "a pseudo random numbers generator based on chaotic iterations application to watermarking"

Connected through hyperedge HE-3 (induced by source paper "a robust data hiding process contributing to the development of a semantic web"):
  with members:
    - "application of steganography for anonymity through the internet"
    - "steganography a class of secure and robust algorithms"

Connected through hyperedge HE-4 (induced by source paper "fpga design for pseudorandom number generator based on chaotic iteration used in information hiding application"):
  with members:
    - "hash functions using chaotic iterations"
    - "an optimization technique on pseudorandom generators based on chaotic iterations"
    - "a new chaos based watermarking algorithm"
    - "steganography a class of secure and robust algorithms"
    - "evaluating quality of chaotic pseudo random generators application to information hiding"
    - "topological chaos and chaotic iterations application to hash functions"

Connected through hyperedge HE-5 (induced by source paper "neural networks and chaos construction evaluation of chaotic networks and prediction of chaos with multilayer feedforward networks"):
  with members:
    - "hash functions using chaotic iterations"
    - "a new chaos based watermarking algorithm"

Connected through hyperedge HE-6 (induced by source paper "two security layers for hierarchical data aggregation in sensor networks"):
  with members:
    - "hash functions using chaotic iterations"

Connected through hyperedge HE-7 (induced by source paper "quality analysis of a chaotic proven keyed hash function"):
  with members:
    - "performance analysis of a keyed hash function based on discrete and chaotic proven iterations"

Connected through hyperedge HE-8 (induced by source paper "application of steganography for anonymity through the internet"):
  with members:
    - "steganography a class of secure and robust algorithms"
    - "class of trustworthy pseudo random number generators"
    - "a complexity approach for steganalysis"

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)