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: "extracting and verifying cryptographic models from c protocol code by symbolic execution"
  Abstract: Consider the problem of verifying security properties of a cryptographic protocol coded in C. We propose an automatic solution that needs neither a pre-existing protocol description nor manual annotation of source code. First, symbolically execute the C program to obtain symbolic descriptions for the network messages sent by the protocol. Second, apply algebraic rewriting to obtain a process calculus description. Third, run an existing protocol analyser (ProVerif) to prove security properties or find attacks. We formalise our algorithm and appeal to existing results for ProVerif to establish computational soundness under suitable circumstances. We analyse only a single execution path, so our results are limited to protocols with no significant branching. The results in this paper provide the first computationally sound verification of weak secrecy and authentication for (single execution paths of) C code.

Connected through hyperedge HE-1 (induced by source paper "verifying software vulnerabilities in iot cryptographic protocols"):
  with members:
    - "v fuzz vulnerability oriented evolutionary fuzzing"
    - "improving function coverage with munch a hybrid fuzzing and directed symbolic execution approach"
    - "on the security of 2 key triple des"
    - "smt based bounded model checking for embedded ansi c software"

Connected through hyperedge HE-2 (induced by source paper "computational soundness for dalvik bytecode"):
  with members:
    - "computational soundness results for stateful applied pi calculus"
    - "the foundational cryptography framework"

Connected through hyperedge HE-3 (induced by source paper "verifying cryptographic security implementations in c using automated model extraction"):
  with members:
    - "guiding a general purpose c verifier to prove cryptographic protocols"
    - "a formally verified compiler back end"
    - "automatic verification of correspondences for security protocols"
    - "a static analyzer for large safety critical software"
    - "inductive analysis of the internet protocol tls"

Connected through hyperedge HE-4 (induced by source paper "a formal methodology for integral security design and verification of network protocols"):
  with members:
    - "formal security analysis of registration protocols for interactive systems a methodology and a case of study"

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)