  This paper introduces an imperative process algebra based on ACP (Algebra of
Communicating Processes). Like other imperative process algebras, this process
algebra deals with processes of the kind that arises from the execution of
imperative programs. It distinguishes itself from already existing imperative
process algebras among other things by supporting abstraction from actions that
are considered not to be visible. The support of abstraction of this kind opens
interesting application possibilities of the process algebra. This paper goes
briefly into the possibility of information-flow security analysis of the kind
that is concerned with the leakage of confidential data. For the presented
axiomatization, soundness and semi-completeness results with respect to a
notion of branching bisimulation equivalence are established.
