We present an automatic, terminating method for verifying confidentiality properties, and to a lesser extent freshness properties of cryptographic protocols. It is based on a safe abstract interpretation of cryptographic protocols using a specific extension of tree automata, _-parameterized tree automata, which mix automata-theoretic techniques with deductive features. Contrary to most model-ch...

Numerous computer systems use dynamic control and data structures of unbounded size. These data structures have often the character of trees or they can be encoded as trees with some additional pointers. This is exploited by some currently intensively studied techniques of formal verification that represent an infinite number of states using a finite tree automaton. However, currently there is ...

We show that the inclusion problem is decidable for rational languages of words indexed by scattered countable linear orderings. The method leans on a reduction to the decidability of the monadic second order theory of the infinite binary tree [9]. Mathematics Subject Classification. 68Q45, 03D05.

We develop a verification method based on a novel use of tree automata to represent heap configurations to allow verification of important properties—such as no nullpointer dereferences, absence of memory leaks, etc.—for programs manipulating complex dynamically linked data structures. In our approach, a heap is split into several “separated” parts such that each of them can be represented by a...

Determinisation is an important concept in the theory of finite tree automata. However the complexity of the textbook procedure for determinisation is such that it is not viewed as a being a practical procedure for manipulating tree automata, even fairly small ones. The computational problems are exacerbated when an automaton has to be both determinised and completed, for instance to compute th...

Determinisation is an important concept in the theory of finite tree automata. However the complexity of the textbook procedure for determinisation is such that it is not viewed as a being a practical procedure for manipulating tree automata, even fairly small ones. The computational problems are exacerbated when an automaton has to be both determinised and completed, for instance to compute th...

Using the concept of progress measure, we give a new proof of Rabin’s fundamental result that the languages defined by tree automata are closed under complementation. To do this we show that for certain infinite games based on tree automata, an immediate determinacy property holds for the player who is trying to win according to a Rabin acceptance condition. Immediate determinancy is stronger t...

We show how the tree-automata techniques proposed by Lugiez and Schnoebelen apply to the reachability analysis of RPPS systems. Using these techniques requires that we express the states of RPPS systems in a tailor-made process rewrite system where reachability is a relation recognizable by nite tree-automata.

We consider weighted tree automata with discounting over commutative semirings. For their behaviors we establish a Kleene theorem and an MSOlogic characterization. We introduce also weighted Muller tree automata with discounting over the max-plus and the min-plus semirings, and we show their expressive equivalence with two fragments of weighted MSO-sentences.

We consider tree-walking automata using k pebbles. The pebbles are either strong (can be lifted from anywhere) or weak (can be lifted only when the automaton is on it). For each k, we give the precise complexities of the problems of emptiness and inclusion of tree-walking automata using k pebbles.