Acta Informatica

, Volume 17, Issue 3, pp 349–364 | Cite as

On some decidable properties of finite state translations

  • A. Demers
  • C. Keleman
  • B. Reusch


In this paper we present algorithms to decide: 1) single-valuedness of nondeterministic finite transducers, 2) equivalence of single-valued transducers, and 3) whether a given nondeterministic finite transduction can be realized by a deterministic transducer. When such a deterministic realization is possible our proof gives an effective construction of the deterministic transducer.

The decidability of single-valuedness and equivalence for a-transducers has been obtained independently by Blattner and Head [3]. Our results introduce different characterizations for decidability and use a different proof that is interesting on its own.

We began this research by generalizing the results about decoding automata presented in [5]. A report of these results with a heavy emphasis placed on applications to crytography appears in [6]. This paper presents results applicable in the more general area of finite state translations.


Information System Operating System Data Structure Communication Network Information Theory 


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Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • A. Demers
    • 1
  • C. Keleman
    • 1
  • B. Reusch
    • 1
  1. 1.Department of Computer ScienceCornell UniversityIthacaUSA

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