Security Protocols II: Syntax and Operational Semantics (Part 1)

The Dolev-Yao-Style IntruderDolev-Yao ClosureDefinitionGiven a set of terms M we define DY(M) as the least closure of Munder the following rules:Axiom (m ∈ M) sm ∈ DY(M)t 1 ∈ DY(M) . . . t n ∈ DY(M)f (t 1 , . . . , t n ) ∈ DY(M)〈m 1 , m 2 〉 ∈ DY(M)m i ∈ DY(M)∈ DY(M)t ∈ DY(M)Algebra (s ≈ t)Composition (f ∈ Σ p )Proj i{|m|} k ∈ DY(M) k ∈ DY(M)m ∈ DY(M){m} k ∈ DY(M) inv(k) ∈ DY(M)DecAsymm ∈ DY(M)DecSym{m} inv(k) ∈ DY(M)OpenSigm ∈ DY(M)Decidability/complexity: in module 5.Sebastian Mödersheim FMSEC Module 3, v.2 5.10.2009 26 of 36