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: "steganography a class of secure and robust algorithms"
  Abstract: This research work presents a new class of non-blind information hiding algorithms that are stego-secure and robust. They are based on some finite domains iterations having the Devaney's topological chaos property. Thanks to a complete formalization of the approach we prove security against watermark-only attacks of a large class of steganographic algorithms. Finally a complete study of robustness is given in frequency DWT and DCT domains.

Connected through hyperedge HE-1 (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"
    - "chaotic iterations versus spread spectrum chaos and stego security"

Connected through hyperedge HE-2 (induced by source paper "on the usefulness of information hiding techniques for wireless sensor networks security"):
  with members:
    - "low cost monitoring and intruders detection using wireless video sensor networks"

Connected through hyperedge HE-3 (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"
    - "evaluating quality of chaotic pseudo random generators application to information hiding"
    - "topological chaos and chaotic iterations application to hash functions"
    - "chaotic iterations versus spread spectrum chaos and stego security"

Connected through hyperedge HE-4 (induced by source paper "application of steganography for anonymity through the internet"):
  with members:
    - "class of trustworthy pseudo random number generators"
    - "a complexity approach for steganalysis"
    - "chaotic iterations versus spread spectrum chaos and stego security"

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)