On ambiguity of DTOL systems

  • K. G. Subramanian
  • Do Van Long
  • Rani Siromoney
Session 1 Automata And Formal Languages
Part of the Lecture Notes in Computer Science book series (LNCS, volume 287)


A DTOL system is unambiguous if no two different sequences of morphisms yield the same word from an axiom. A subfamily of DTOL systems with decidable ambiguity problem is exhibited. Four different sufficient conditions for a DTOL system to be unambiguous are formulated. These DTOL systems are very much suitable for the construction of public key cryptosystems based on L systems. We also prove that for DOL systems over a binary alphabet, the ambiguity problem is effectively decidable. This result has useful applications in the construction of public key cryptosystems which encrypt plain-texts over a binary alphabet using a TOL system obtained from an underlying unambiguous DOL system.


Ambiguity Problem Prefix Code Binary Alphabet Uniform Code Madras Christian College 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • K. G. Subramanian
    • 1
  • Do Van Long
    • 1
  • Rani Siromoney
    • 1
  1. 1.Department of MathematicsMadras Christian College, TambaramMadras

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