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 tractability aspects of optimal resource allocation in ofdma systems"
  Abstract: Joint channel and rate allocation with power minimization in orthogonal frequency-division multiple access (OFDMA) has attracted extensive attention. Most of the research has dealt with the development of sub-optimal but low-complexity algorithms. In this paper, the contributions comprise new insights from revisiting tractability aspects of computing optimum. Previous complexity analyses have been limited by assumptions of fixed power on each subcarrier, or power-rate functions that locally grow arbitrarily fast. The analysis under the former assumption does not generalize to problem tractability with variable power, whereas the latter assumption prohibits the result from being applicable to well-behaved power-rate functions. As the first contribution, we overcome the previous limitations by rigorously proving the problem's NP-hardness for the representative logarithmic rate function. Next, we extend the proof to reach a much stronger result, namely that the problem remains NP-hard, even if the channels allocated to each user is restricted to a consecutive block with given size. We also prove that, under these restrictions, there is a special case with polynomial-time tractability. Then, we treat the problem class where the channels can be partitioned into an arbitrarily large but constant number of groups, each having uniform gain for every individual user. For this problem class, we present a polynomial-time algorithm and prove optimality guarantee. In addition, we prove that the recognition of this class is polynomial-time solvable.

Connected through hyperedge HE-1 (induced by source paper "jammer assisted resource allocation in secure ofdma with untrusted users"):
  with members:
    - "principles of physical layer security in multiuser wireless networks a survey"
    - "secrecy sum rates for multi user mimo regularized channel inversion precoding"
    - "on the complexity of joint subcarrier and power allocation for multi user ofdma systems"
    - "interference assisted secret communication"
    - "power and subcarrier allocation for physical layer security in ofdma based broadband wireless networks"
    - "a quantitative measure of fairness and discrimination for resource allocation in shared computer systems"

Connected through hyperedge HE-2 (induced by source paper "resource optimization with flexible numerology and frame structure for heterogeneous services"):
  with members:
    - "an examination of the benefits of scalable tti for heterogeneous traffic management in 5g networks"
    - "joint scheduling of urllc and embb traffic in 5g wireless networks"
    - "resource scheduling for mixed traffic types with scalable tti in dynamic tdd systems"
    - "a performance study of energy minimization for interleaved and localized fdma"
    - "filtered ofdm enabler for flexible waveform in the 5th generation cellular networks"

Connected through hyperedge HE-3 (induced by source paper "compressive sensing based user clustering for downlink noma systems with decoding power"):
  with members:
    - "energy efficiency of downlink transmission strategies for cloud radio access networks"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"
    - "energy consumption of vlsi decoders"

Connected through hyperedge HE-4 (induced by source paper "power and channel allocation for non orthogonal multiple access in 5g systems tractability and computation"):
  with members:
    - "noma an information theoretic perspective"
    - "optimal joint power and subcarrier allocation for mc noma systems"
    - "fairness for non orthogonal multiple access in 5g systems"
    - "uplink non orthogonal multiple access for 5g wireless networks"
    - "what will 5g be"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"
    - "on the complexity of joint subcarrier and power allocation for multi user ofdma systems"
    - "gaussian interference channel capacity to within one bit"

Connected through hyperedge HE-5 (induced by source paper "content caching and distribution in smart grid enabled wireless networks"):
  with members:
    - "greendelivery proactive content caching and push with energy harvesting based small cells"
    - "green energy aware avatar migration strategy in green cloudlet networks"
    - "complexity analysis of joint subcarrier and power allocation for the cellular downlink ofdma system"
    - "joint spectrum and power allocation for multi node cooperative wireless systems"
    - "on green energy powered cognitive radio networks"
    - "the throughput outage tradeoff of wireless one hop caching networks"

Connected through hyperedge HE-6 (induced by source paper "complexity analysis of joint subcarrier and power allocation for the cellular downlink ofdma system"):
  with members:
    - "on the complexity of joint subcarrier and power allocation for multi user ofdma 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.NI(Networking and Internet Architecture)