Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: How to Guarantee Secrecy for Cryptographic Protocols   In this paper we propose a general definition of secrecy for cryptographic
protocols in the Dolev-Yao model. We give a sufficient condition ensuring
secrecy for protocols where rules have encryption depth at most two, that is
satisfied by almost all practical protocols. The only allowed primitives in the
class of protocols we consider are pairing and encryption with atomic keys.
Moreover, we describe an algorithm of practical interest which transforms a
cryptographic protocol into a secure one from the point of view of secrecy,
without changing its original goal with respect to secrecy of nonces and keys,
provided the protocol satisfies some conditions. These conditions are not very
restrictive and are satisfied for most practical protocols.

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The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
29
The categories of this paper are: funct-an
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: eess
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th