On ambiguity of DTOL systems
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.
KeywordsAmbiguity Problem Prefix Code Binary Alphabet Uniform Code Madras Christian College
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