Secure Resource Access for Mobile Agents

. In open distributed systems of mobile agents, where code from remote sites may run locally, protection of sensitive data and system resources is of paramount importance. We present a capability-based typing system that provides such protection, using a mix of static and runtime typing. We formalize security violations as runtime errors and prove that, using our semantics, runtime errors cannot occur at "good" sites, i.e. sites under control of a particular administrative domain. KEYWORDS. Security, Type theory and type systems, Mobile agents, Open systems, Concurrency, Semantics. 1 Introduction Highly distributed networks, in which mobile agents move from site to site, are fast becoming a reality. In such networks security issues, for example ensuring the integrity of a local address space or limiting access to certain data to appropriate principals, is of the utmost importance. This is particularly so in open networks where remote locations may, intentionally or otherwise, harbor m..