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: "data hiding techniques using prime and natural numbers"
  Abstract: In this paper, a few novel data hiding techniques are proposed. These techniques are improvements over the classical LSB data hiding technique and the Fibonacci LSB data-hiding technique proposed by Battisti et al. \cite{r1}. The classical LSB technique is the simplest, but using this technique it is possible to embed only in first few bit-planes, since image quality becomes drastically distorted when embedding in higher bit-planes. Battisti et al. \cite{r1} proposed an improvement over this by using Fibonacci decomposition technique and generating a different set of virtual bit-planes all together, thereby increasing the number of bit-planes. In this paper, first we mathematically model and generalize this particular approach of virtual bit-plane generation. Then we propose two novel embedding techniques, both of which are special-cases of our generalized model. The first embedding scheme is based on decomposition of a number (pixel-value) in sum of prime numbers, while the second one is based on decomposition in sum of natural numbers. Each of these particular representations generates a different set of (virtual) bit-planes altogether, suitable for embedding purposes. They not only allow one to embed secret message in higher bit-planes but also do it without much distortion, with a much better stego-image quality, in a reliable and secured manner, guaranteeing efficient retrieval of secret message. A comparative performance study between the classical Least Significant Bit (LSB) method, the data hiding technique using Fibonacci -p-Sequence decomposition and our proposed schemes has been done. Theoretical analysis indicates that image quality of the stego-image hidden by the technique using Fibonacci decomposition improves against simple LSB substitution method, while the same using the prime decomposition method improves drastically against that using Fibonacci decomposition technique, and finally the natural number decomposition method is a further improvement against that using prime decomposition technique. Also, optimality for the last technique is proved. For both of our data-hiding techniques, the experimental results show that, the stego-image is visually indistinguishable from the original cover image.

Connected through hyperedge HE-1 (induced by source paper "application of multi factor authentication in internet of things domain"):
  with members:
    - "detection and prevention of botnets and malware in an enterprise network"
    - "a multi dimensional approach towards intrusion detection system"
    - "a multi factor security protocol for wireless payment secure web authentication using mobile devices"
    - "embedding secret data in html web page"
    - "voice recognition algorithms using mel frequency cepstral coefficient mfcc and dynamic time warping dtw techniques"
    - "a semi distributed reputation based intrusion detection system for mobile adhoc networks"

Connected through hyperedge HE-2 (induced by source paper "comparative analysis of cryptography library in iot"):
  with members:
    - "sleep deprivation attack detection in wireless sensor network"
    - "efficient implementation of elliptic curve cryptography using low power digital signal processor"
    - "embedding secret data in html web page"
    - "a semi distributed reputation based intrusion detection system for mobile adhoc networks"

Connected through hyperedge HE-3 (induced by source paper "multipath routing of fragmented data transfer in a smart grid environment"):
  with members:
    - "detection and prevention of botnets and malware in an enterprise network"
    - "ant colony based routing for mobile ad hoc networks towards improved quality of services"
    - "an lsb data hiding technique using natural number decomposition"

Connected through hyperedge HE-4 (induced by source paper "iot enabled insurance ecosystem possibilities challenges and risks"):
  with members:
    - "sleep deprivation attack detection in wireless sensor network"
    - "a novel multipath approach to security in mobile ad hoc networks manets"
    - "a semi distributed reputation based intrusion detection system for mobile adhoc networks"

Connected through hyperedge HE-5 (induced by source paper "synchronous relaying of sensor data"):
  with members:
    - "study of encryption and decryption of wave file in image formats"
    - "ant colony based routing for mobile ad hoc networks towards improved quality of services"
    - "sleep deprivation attack detection in wireless sensor network"
    - "grid security and integration with minimal performance degradation"
    - "a semi distributed reputation based intrusion detection system for mobile adhoc networks"
    - "steganography of voip streams"
    - "an lsb data hiding technique using natural number decomposition"

Connected through hyperedge HE-6 (induced by source paper "steganalysis detecting lsb steganographic techniques"):
  with members:
    - "reversible and irreversible data hiding technique"
    - "a survey on various data hiding techniques and their comparative analysis"
    - "steganography and steganalysis different approaches"
    - "an lsb data hiding technique using prime numbers"
    - "an lsb data hiding technique using natural number decomposition"

Connected through hyperedge HE-7 (induced by source paper "increasing security in cloud environment"):
  with members:
    - "rism reputation based intrusion detection system for mobile ad hoc networks"
    - "detection and prevention of botnets and malware in an enterprise network"
    - "a paxos based state machine replication system for anomaly detection"
    - "a multi dimensional approach towards intrusion detection system"
    - "a hybrid approach towards intrusion detection based on artificial immune system and soft computing"
    - "a survey on security issues in cloud computing"
    - "a new trusted and collaborative agent based approach for ensuring cloud security"
    - "grid security and integration with minimal performance degradation"

Connected through hyperedge HE-8 (induced by source paper "study of encryption and decryption of wave file in image formats"):
  with members:
    - "rism reputation based intrusion detection system for mobile ad hoc networks"
    - "ant colony based routing for mobile ad hoc networks towards improved quality of services"
    - "steganography and steganalysis different approaches"
    - "a new trusted and collaborative agent based approach for ensuring cloud security"
    - "a semi distributed reputation based intrusion detection system for mobile adhoc networks"
    - "an lsb data hiding technique using natural number decomposition"

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)