Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Shor-Preskill Type Security-Proofs for Concatenated Bennett-Brassard
  1984 Quantum Key Distribution Protocol   We discuss long code problems in the Bennett-Brassard 1984 (BB84) quantum key
distribution protocol and describe how they can be overcome by concatenation of
the protocol. Observing that concatenated modified Lo-Chau protocol finally
reduces to the concatenated BB84 protocol, we give the unconditional security
of the concatenated BB84 protocol.

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The categories of this paper are: astro-ph
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: stat
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The categories of this paper are: hep-ex
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The categories of this paper are: funct-an
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The categories of this paper are: ao-sci
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The categories of this paper are: supr-con
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The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin