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: "on the security defects of an image encryption scheme"
  Abstract: This paper studies the security of a recently-proposed chaos-based image encryption scheme and points out the following problems: (1) there exist a number of invalid keys and weak keys, and some keys are partially equivalent for encryption/decryption; (2) given one chosen plain-image, a subkey K"1"0 can be guessed with a smaller computational complexity than that of the simple brute-force attack; (3) given at most 128 chosen plain-images, a chosen-plaintext attack can possibly break the following part of the secret key: K"imod128"i"="4^1^0, which works very well when K"1"0 is not too large; (4) when K"1"0 is relatively small, a known-plaintext attack can be carried out with only one known plain-image to recover some visual information of any other plain-images encrypted by the same key.

Connected through hyperedge HE-1 (induced by source paper "an optical image encryption scheme based on depth conversion integral imaging and chaotic maps"):
  with members:
    - "a general quantitative cryptanalysis of permutation only multimedia ciphers against plaintext attacks"
    - "cryptanalyzing an encryption scheme based on blind source separation"

Connected through hyperedge HE-2 (induced by source paper "cryptanalyzing image encryption using chaotic logistic map"):
  with members:
    - "breaking a chaotic image encryption algorithm based on perceptron model"
    - "breaking a modified substitution diffusion image cipher based on chaotic standard and logistic maps"
    - "cryptanalysis of an image encryption scheme based on a compound chaotic sequence"

Connected through hyperedge HE-3 (induced by source paper "cryptanalyzing a rgb image encryption algorithm based on dna encoding and chaos map"):
  with members:
    - "breaking a novel image encryption scheme based on improved hyperchaotic sequences"
    - "a rgb image encryption algorithm based on dna encoding and chaos map"
    - "breaking an image encryption algorithm based on chaos"

Connected through hyperedge HE-4 (induced by source paper "breaking a chaotic image encryption algorithm based on modulo addition and xor operation"):
  with members:
    - "breaking an image encryption algorithm based on chaos"
    - "breaking a chaotic cryptographic scheme based on composition maps"
    - "on the security of the yen guo s domino signal encryption algorithm dsea"
    - "chosen plaintext cryptanalysis of a clipped neural network based chaotic cipher"
    - "on the security of the yi tan siew chaotic cipher"

Connected through hyperedge HE-5 (induced by source paper "breaking a novel image encryption scheme based on improved hyperchaotic sequences"):
  with members:
    - "breaking a chaotic image encryption algorithm based on modulo addition and xor operation"
    - "breaking a chaotic image encryption algorithm based on perceptron model"
    - "on the security of the yi tan siew chaotic cipher"

Connected through hyperedge HE-6 (induced by source paper "breaking a novel colour image encryption algorithm based on chaos"):
  with members:
    - "cryptanalysis of an image encryption scheme based on a compound chaotic sequence"
    - "a general quantitative cryptanalysis of permutation only multimedia ciphers against plaintext attacks"

Connected through hyperedge HE-7 (induced by source paper "breaking an image encryption algorithm based on chaos"):
  with members:
    - "breaking a modified substitution diffusion image cipher based on chaotic standard and logistic maps"
    - "cryptanalysis of an image encryption scheme based on a compound chaotic sequence"
    - "a general quantitative cryptanalysis of permutation only multimedia ciphers against plaintext attacks"

Connected through hyperedge HE-8 (induced by source paper "cryptanalyzing a chaos based image encryption algorithm using alternate structure"):
  with members:
    - "a general quantitative cryptanalysis of permutation only multimedia ciphers against plaintext attacks"

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)