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: "convexity conditions for 802 11 wlans"
  Abstract: In this paper we characterise the maximal convex subsets of the (non-convex) rate region in 802.11 WLANs. In addition to being of intrinsic interest as a fundamental property of 802.11 WLANs, this characterisation can be exploited to allow the wealth of convex optimisation approaches to be applied to 802.11 WLANs.

Connected through hyperedge HE-1 (induced by source paper "fair coexistence of scheduled and random access wireless networks unlicensed lte wifi"):
  with members:
    - "srslte an open source platform for lte evolution and experimentation"
    - "small cell traffic balancing over licensed and unlicensed bands"
    - "unlicensed lte wifi coexistence is lbt inherently fairer than csat"
    - "rigorous and practical proportional fair allocation for multi rate wi fi"

Connected through hyperedge HE-2 (induced by source paper "proportional fair mu mimo in 802 11 wlans"):
  with members:
    - "on the performance of packet aggregation in ieee 802 11ac mu mimo wlans"
    - "max min fairness in 802 11 mesh networks"

Connected through hyperedge HE-3 (induced by source paper "thwarting selfish behavior in 802 11 wlans"):
  with members:
    - "a game theoretic approach to distributed opportunistic scheduling"
    - "mac design for wifi infrastructure networks a game theoretic approach"

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)