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: "tripod of requirements in horizontal heterogeneous mobile cloud computing"
  Abstract: Recent trend of mobile computing is emerging toward executing resource-intensive applications in mobile devices regardless of underlying resource restrictions (e.g. limited processor and energy) that necessitate imminent technologies. Prosperity of cloud computing in stationary computers breeds Mobile Cloud Computing (MCC) technology that aims to augment computing and storage capabilities of mobile devices besides conserving energy. However, MCC is more heterogeneous and unreliable (due to wireless connectivity) compare to cloud computing. Problems like variations in OS, data fragmentation, and security and privacy discourage and decelerate implementation and pervasiveness of MCC. In this paper, we describe MCC as a horizontal heterogeneous ecosystem and identify thirteen critical metrics and approaches that influence on mobile-cloud solutions and success of MCC. We divide them into three major classes, namely ubiquity, trust, and energy efficiency and devise a tripod of requirements in MCC. Our proposed tripod shows that success of MCC is achievable by reducing mobility challenges (e.g. seamless connectivity, fragmentation), increasing trust, and enhancing energy efficiency.

Connected through hyperedge HE-1 (induced by source paper "cloud based augmentation for mobile devices motivation taxonomies and open challenges"):
  with members:
    - "mobile cloud computing a review on smartphone augmentation approaches"
    - "sami service based arbitrated multi tier infrastructure for mobile cloud computing"
    - "momcc market oriented architecture for mobile cloud computing based on service oriented architecture"
    - "cloudmonitor profiling power usage"
    - "a survey of green networking research"
    - "the anatomy of the grid enabling scalable virtual organizations"

Connected through hyperedge HE-2 (induced by source paper "sami service based arbitrated multi tier infrastructure for mobile cloud computing"):
  with members:
    - "mobile cloud computing a review on smartphone augmentation approaches"

Connected through hyperedge HE-3 (induced by source paper "momcc market oriented architecture for mobile cloud computing based on service oriented architecture"):
  with members:
    - "mobile cloud computing a review on smartphone augmentation approaches"

Connected through hyperedge HE-4 (induced by source paper "virtual machine migration a resource intensive outsourcing mechanism for mobile cloud computing"):
  with members:
    - "mobile cloud computing a review on smartphone augmentation approaches"

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.DC(Distributed, Parallel, and Cluster Computing)