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: "vcache caching dynamic documents"
  Abstract: The traditional web caching is currently limited to static documents only. A page generated on the fly from a server side script may have different contents on different accesses and hence cannot be cached. A number of proposals for attacking the problem have emerged based on the observation that different instances of a dynamic document are usually quite similar in most cases, i.e. they have a lot of common HTML code. In this paper, we first review these related techniques and show their inadequacy for practical use. We then present a general and fully automatic technique called Vcache based on the decomposition of dynamic documents into a hierarchy of templates and bindings. The technique is designed keeping in mind languages like Perl and C etc that generate the documents using low-level print like statements. These languages together, account for the largest number of dynamic documents on the web.

Connected through hyperedge HE-1 (induced by source paper "increasing security in cloud environment"):
  with members:
    - "rism reputation based intrusion detection system for mobile ad hoc networks"
    - "detection and prevention of botnets and malware in an enterprise network"
    - "a paxos based state machine replication system for anomaly detection"
    - "a multi dimensional approach towards intrusion detection system"
    - "a hybrid approach towards intrusion detection based on artificial immune system and soft computing"
    - "a survey on security issues in cloud computing"
    - "a new trusted and collaborative agent based approach for ensuring cloud security"
    - "grid security and integration with minimal performance degradation"

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.CR(Cryptography and Security)