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: "on the performance of rf fso links with and without hybrid arq"
  Abstract: This paper studies the performance of hybrid radio-frequency (RF) and free-space optical (FSO) links assuming perfect channel state information (CSI) at the receiver. Considering the cases with and without hybrid automatic repeat request (HARQ), we derive closed-form expressions for the message decoding probabilities as well as the throughput and the outage probability of the RF-FSO setups. We also evaluate the effect of adaptive power allocation and different channel conditions on the throughput and the outage probability. The results show the efficiency of the RF-FSO links in different conditions.

Connected through hyperedge HE-1 (induced by source paper "on the performance of millimeter wave based rf fso multi hop and mesh networks"):
  with members:
    - "performance analysis of free space optical links over m a laga mathcal m turbulence channels with pointing errors"
    - "unified performance analysis of mixed radio frequency free space optical dual hop transmission systems"
    - "unified performance analysis of mixed line of sight rf fso fixed gain dual hop transmission systems"
    - "impact of pointing errors on the performance of mixed rf fso dual hop transmission systems"
    - "on the benefits of partial channel state information for repetition protocols in block fading channels"
    - "on the capacity of free space optical intensity channels"

Connected through hyperedge HE-2 (induced by source paper "performance analysis of rf fso multi hop networks"):
  with members:
    - "on the performance of millimeter wave based rf fso multi hop and mesh networks"
    - "unified performance analysis of mixed radio frequency free space optical dual hop transmission systems"
    - "impact of pointing errors on the performance of mixed rf fso dual hop transmission systems"

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.IT(Information Theory)