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: "standards for enabling heterogeneous iaas cloud federations"
  Abstract: Technology market is continuing a rapid growth phase where different resource providers and Cloud Management Frameworks are positioning to provide ad-hoc solutions-as management interfaces, information discovery or billing-trying to differentiate from competitors resulting in incompatibilites between them when addressing more complex scenarios like federated clouds.Therefore, grasping interoperability problems present in current infrastructures by studying how existing and emerging standards could enhance the cloud user experience.In this paper we will review the current open challenges in Infrastructure as a Service cloud interoperability and federation, as well as point to the potential standards that should alleviate these problems. We will describe the main challenges regarding cloud federation and in-teroperability.We will showcase and review the existing and emerging standards that can be use to tackle the gaps in cloud federations.

Connected through hyperedge HE-1 (induced by source paper "orchestrating complex application architectures in heterogeneous clouds"):
  with members:
    - "improved cloud resource allocation how indigo datacloud is overcoming the current limitations in cloud schedulers"
    - "indigo datacloud foundations and architectural description of a platform as a service oriented to scientific computing"
    - "analysis of scientific cloud computing requirements"
    - "phenomenology tools on cloud infrastructures using openstack"

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.NI(Networking and Internet Architecture)