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: "what type of distribution for packet delay in a global network should be used in the control theory"
  Abstract: In this paper correspondence between experimental data for packet delay and two theoretical types of distribution is investigated. Calculations have shown that the exponential distribution describes the data on network delay better, than truncated normal distribution. Precision experimental data to within microseconds are gathered by means of the RIPE Test Box. In addition to exact measurements the data gathered by means of the utility {\em ping} has been parsed that has not changed the main result. As a result, the equation for an exponential distribution, in the best way describing process of packet delay in a TCP/IP based network is written. The search algorithm for key parameters as for normal, and an exponential distribution is resulted.

Connected through hyperedge HE-1 (induced by source paper "packet pair technique for available bandwidth estimation in ipv6 network"):
  with members:
    - "simulation technique for available bandwidth estimation"
    - "estimation of available bandwidth and measurement infrastructure for russian segment of internet"

Connected through hyperedge HE-2 (induced by source paper "simulation technique for available bandwidth estimation"):
  with members:
    - "throughput metrics and packet delay in tcp ip networks"
    - "estimation of available bandwidth and measurement infrastructure for russian segment of internet"

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)