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: "internet of things security and forensics challenges and opportunities"
  Abstract: Abstract   The Internet of Things (IoT) envisions pervasive, connected, and smart nodes interacting autonomously while offering all sorts of services. Wide distribution, openness and relatively high processing power of IoT objects made them an ideal target for cyber attacks. Moreover, as many of IoT nodes are collecting and processing private information, they are becoming a goldmine of data for malicious actors. Therefore, security and specifically the ability to detect compromised nodes, together with collecting and preserving evidences of an attack or malicious activities emerge as a priority in successful deployment of IoT networks. In this paper, we first introduce existing major security and forensics challenges within IoT domain and then briefly discuss about papers published in this special issue targeting identified challenges.

Connected through hyperedge HE-1 (induced by source paper "architectural software patterns for the development of iot smart applications"):
  with members:
    - "advertising in the iot era vision and challenges"
    - "software platforms for smart cities concepts requirements challenges and a unified reference architecture"
    - "low power wide area networks an overview"
    - "internet of things iot a vision architectural elements and future directions"

Connected through hyperedge HE-2 (induced by source paper "a light weight authentication scheme for air force internet of things"):
  with members:
    - "usbee air gap covert channel via electromagnetic emission from usb"
    - "device fingerprinting in wireless networks challenges and opportunities"
    - "internet of things iot a vision architectural elements and future directions"
    - "using the physical layer for wireless authentication in time variant channels"

Connected through hyperedge HE-3 (induced by source paper "a reliable iot based embedded health care system for diabetic patients"):
  with members:
    - "iot based secure embedded scheme for insulin pump data acquisition and monitoring"

Connected through hyperedge HE-4 (induced by source paper "emerging from the cloud a bibliometric analysis of cloud forensics studies"):
  with members:
    - "greening cloud enabled big data storage forensics syncany as a case study"
    - "forensic investigation of p2p cloud storage bittorrent sync as a case study"
    - "cloud storage forensics analysis of data remnants on spideroak justcloud and pcloud"
    - "a cyber kill chain based taxonomy of banking trojans for evolutionary computational intelligence"
    - "investigating storage as a service cloud platform pcloud as a case study"
    - "know abnormal find evil frequent pattern mining for ransomware threat hunting and intelligence"
    - "cloud storage forensic hubic as a case study"
    - "calm before the storm the challenges of cloud computing in digital forensics"

Connected through hyperedge HE-5 (induced by source paper "a model for android and ios applications risk calculation cvss analysis and enhancement using case control studies"):
  with members:
    - "greening cloud enabled big data storage forensics syncany as a case study"
    - "mobile phone forensics an investigative framework based on user impulsivity and secure collaboration errors"
    - "a cyber kill chain based taxonomy of banking trojans for evolutionary computational intelligence"
    - "forensics analysis of android mobile voip apps"
    - "an android cloud storage apps forensic taxonomy"
    - "know abnormal find evil frequent pattern mining for ransomware threat hunting and intelligence"
    - "forensic investigation of social media and instant messaging services in firefox os facebook twitter google telegram openwapp and line as case studies"

Connected through hyperedge HE-6 (induced by source paper "empirical vulnerability analysis of automated smart contracts security testing on blockchains"):
  with members:
    - "tool demonstration fsolidm for designing secure ethereum smart contracts"
    - "a semantic framework for the security analysis of ethereum smart contracts"
    - "smart contract based access control for the internet of things"
    - "nonreciprocity compensation combined with turbo codes for secret key generation in vehicular ad hoc social iot networks"
    - "designing secure ethereum smart contracts a finite state machine based approach"
    - "statistical model checking an overview"

Connected through hyperedge HE-7 (induced by source paper "a novel iot architecture based on 5g iot and next generation technologies"):
  with members:
    - "mobile edge computing fog et al a survey and analysis of security threats and challenges"
    - "defining and surveying wireless link virtualization and wireless network virtualization"
    - "what will 5g be"

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)