Client-Server Interactions in Multi-Server Operating Systems: The Mach-US Approach

This paper describes requirements placed upon client-server interaction in a multi-server operating system and how to answer those requirements. Addressed are the problems of binding maintenance in the face of: remote method invocation, forking, binding transfer, authentication, asynchronous interruption, and client crashes. Design and implementation choices are analyzed. The solutions, used by the CMU Mach-US multi-server UNIX 4.3BSD emulation on the Mach3.0 kernel, are described. The lessons learned are applicable to multi-server OS design and should be applicable to object based systems that must resolve these binding problems in a “micro” kernel environment. This research is sponsored by the Advanced Research Projects Agency under contract number DABT63-93-C-0054. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the U.S. Government.