PTnet
Definitions – Siphons and Traps
20/3/2014
CE-653 - PTnet Theory and some
Algorithms
12
}Definition [Siphons (Deadlocks)
and Traps]:
}Let N = (S, T, F) be a
net.
}D ≤ S is a siphon (deadlock) iff D ≠ Ø and •D
≤ D•
}Θ ≤ S is a trap iff Θ ≠ Ø and Θ• ≤ •Θ
}A siphon (deadlock) or
trap is minimal
iff
there exists no deadlock or trap D’ such that D’ ≤ D
there exists no deadlock or trap D’ such that D’ ≤ D
}A siphon (deadlock) or
trap is strongly-connected iff
the subnet generated by D U •D is strongly connected
the subnet generated by D U •D is strongly connected