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: "cloud storage forensic hubic as a case study"
  Abstract: In today's society where we live in a world of constant connectivity, many people are now looking to cloud services in order to store their files so they can have access to them wherever they are. By using cloud services, users can access files anywhere with an internet connection. However, while cloud storage is convenient, it also presents security risks. From a forensics perspective, the increasing popularity of cloud storage platforms, makes investigation into such exploits much more difficult, especially since many platforms such as mobile devices as well as computers are able to use these services. This paper presents investigation of hubiC as one of popular cloud platforms running on Microsoft Windows 8.1. Remaining artefacts pertaining different usage of hubiC namely upload, download, installation and uninstallation on Microsoft Windows 8.1 are presented.

Connected through hyperedge HE-1 (induced by source paper "greening cloud enabled big data storage forensics syncany as a case study"):
  with members:
    - "digital forensic investigation of cloud storage services"
    - "network traffic forensics on firefox mobile os facebook twitter and telegram as case studies"
    - "windows instant messaging app forensics facebook and skype as case studies"
    - "a forensically sound adversary model for mobile devices"
    - "leveraging decentralization to extend the digital evidence acquisition window case study on bittorrent sync"
    - "bittorrent sync first impressions and digital forensic implications"
    - "bittorrent sync network investigation methodology"

Connected through hyperedge HE-2 (induced by source paper "cloudme forensics a case of big data forensic investigation"):
  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"
    - "digital forensic investigation of cloud storage services"
    - "windows instant messaging app forensics facebook and skype as case studies"
    - "a forensically sound adversary model for mobile devices"
    - "leveraging decentralization to extend the digital evidence acquisition window case study on bittorrent sync"
    - "bittorrent sync first impressions and digital forensic implications"

Connected through hyperedge HE-3 (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"
    - "internet of things security and forensics challenges and opportunities"
    - "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"
    - "calm before the storm the challenges of cloud computing in digital forensics"

Connected through hyperedge HE-4 (induced by source paper "investigating storage as a service cloud platform pcloud as a case study"):
  with members:
    - "ubuntu one investigation detecting evidences on client machines"
    - "digital forensic investigation of cloud storage services"
    - "mobile cloud forensics an analysis of seven popular android apps"
    - "bittorrent sync first impressions and digital forensic implications"
    - "using smartphones as a proxy for forensic evidence contained in cloud storage services"

Connected through hyperedge HE-5 (induced by source paper "cloud storage forensics analysis of data remnants on spideroak justcloud and pcloud"):
  with members:
    - "ubuntu one investigation detecting evidences on client machines"
    - "digital forensic investigation of cloud storage services"
    - "mobile cloud forensics an analysis of seven popular android apps"
    - "using smartphones as a proxy for forensic evidence contained in cloud storage services"

Connected through hyperedge HE-6 (induced by source paper "network traffic forensics on firefox mobile os facebook twitter and telegram as case studies"):
  with members:
    - "windows instant messaging app forensics facebook and skype as case studies"
    - "bittorrent sync first impressions and digital forensic implications"

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)