The Eternal System
Abstract
UCSB received a 3 year grant in October 1997, to explore how distributed object applications can perform live upgrades and be made fault-tolerant by replicating their constituent objects, and distributing these replicas across different computers in the network. The technology of Eternal was submitted in response to the October 1998 Object Management Group's Request for Proposals on Fault-Tolerant CORBA. A significant body of work exists in the area of fault-tolerant distributed object systems; much of this work uses object replication to provide fault tolerance. This project was different in that it focused on the degree of transparency to the CORBA application, the degree of modification to the CORBA ORB, the specific mechanisms for achieving replica consistency, and the level of replica consistency provided. Previous efforts to enhance CORBA with fault tolerance attempted to embed fault tolerance mechanisms within the ORB itself. The novel interception approach, developed with this work, allows the transparent insertion of fault tolerance mechanisms underneath the ORB. The interception approach involves 'capturing' specific system calls or library routines used by the application, and modifying their call parameter or return values, or even the calls and routines themselves, to alter the behavior of the application. the advantages to this approach are that neither the ORB nor the objects are ever aware of being 'intercepted' and thus, the new functionality is provided to the application in a manner that is transparent both to the application and to the ORB.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2001
- Accession Number
- ADA393023
Entities
People
- L. E. Moser
- P. M. Melliar-smith
Organizations
- University of California, Santa Barbara