DLS: A CORBA Service for Dynamic Loading of Code

Abstract

Dynamic loading of code is needed when rarely used code should be loaded on demand or when the code to be loaded is not known in advance. In distributed systems it can also be used for code distribution. At the extreme, programming concepts as mobile agents and intelligent proxies rely heavily on dynamic code loading. We focus on the CORBA middleware architecture, which does currently not support code loading. Therefore, we specify a CORBA Dynamic Loading Service (DLS) that allows for transparent loading of code modules into a local CORBA environment, regardless of the used programming language and operating system. We also present an implementation of DLS which is able to identify the code implementation that fits best for the current environment. The selection can not only be based on programming language and processor architecture, etc. but also on versions of available libraries and on locally executed and application-specific compatibility tests. In the end, DLS can be used to implement a generic CORBA life cycle service and intelligent-proxy extensions to CORBA.