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: "an introduction to cyber peacekeeping"
  Abstract: Peacekeeping is a noble and essential activity, helping to bring peace to conflict torn areas and providing security to millions of people around the world. Peacekeepers operate in all domains of war: buffer zones on land, no fly zones in the air and ensuring free passage at sea. With the emergence of cyberspace as a domain of war, questions on the role of peacekeeping in this domain naturally arise. There is extensive research around the topic of cyber warfare, but surprisingly little on how to restore and maintain peace in its aftermath. This is a significant gap which needs addressing. We begin by providing an overview of peacekeeping, describing its overarching goals and principles, using the United Nations model as a reference. We then review existing literature on cyber peacekeeping. The paper progresses to discuss the question of whether cyber peacekeeping is needed, and if so, if it is a plausible concept. We explore some ideas on how cyber peacekeeping could be performed and the challenges cyber peacekeepers will face, before making suggestions on where future work should be focused.

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.CY(Computers and Society)