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: "vvote a verifiable voting system"
  Abstract: The Pret a Voter cryptographic voting system was designed to be flexible and to offer voters a familiar and easy voting experience. In this paper we present a case study of our efforts to adapt Pret a Voter to the idiosyncrasies of elections in the Australian state of Victoria. This technical report includes general background, user experience and details of the cryptographic protocols and human processes. We explain the problems, present solutions, then analyse their security properties and explain how they tie in to other design decisions. We hope this will be an interesting case study on the application of end-to-end verifiable voting protocols to real elections. #R##N#A preliminary version of this paper appeared as the 10th February 2014 version of "Draft Technical Report for VEC vVote System". #R##N#The team involved in developing the vVote design described in this report were: Craig Burton, Chris Culnane, James Heather, Rui Joaquim, Peter Y. A. Ryan, Steve Schneider and Vanessa Teague.

Connected through hyperedge HE-1 (induced by source paper "public evidence from secret ballots"):
  with members:
    - "auditing australian senate ballots"
    - "efficient computation of exact irv margins"
    - "diffsum a simple post election risk limiting audit"
    - "end to end verifiability"
    - "the new south wales ivote system security failures and verification flaws in a live online election"

Connected through hyperedge HE-2 (induced by source paper "distributed end to end verifiable and privacy preserving internet voting systems"):
  with members:
    - "d demos a distributed end to end verifiable internet voting system"
    - "a peered bulletin board for robust use in verifiable voting systems"
    - "interactive consistency in practical mostly asynchronous systems"

Connected through hyperedge HE-3 (induced by source paper "an overview of end to end verifiable voting systems"):
  with members:
    - "a peered bulletin board for robust use in verifiable voting 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.CR(Cryptography and Security)