Keywords: fault tolerance, real time systems, adaptive mechanism
Start Date: 1 January 94 / Status: finished / Duration: 36 months
[ participants / contact]
The main technical objective is to develop adaptive fault tolerant systems that dynamically address real time constraints. This will build on a model for fault tolerant entities for real time computing (FERTs) that allows highly flexible management of redundancy and specification and control of timing constraints. Careful consideration has been given to the off-line and runtime support required to perform time-constrained scheduling and other tasks such as delivery of inputs to redundant copies.
European links: ESPRIT BRA project PDCS 2 (6362), project GUARDS (20716), LTR project DeVa (20072).
In the first two years, several questions concerning the specification, analysis and runtime implementation support for adaptive fault tolerance under real time constraints have been addressed. In more details, they include: refinements of the basic structure of the FERT model in terms of investigations on its feasibility using features of advanced existing real time kernels, and of definition of a communication semantics and communication failure semantics for the FERT entities; scheduling/planning issues, including the planning of task groups and flexible scheduling mechanisms; studies on how to define criteria for distinguishing various possible trade-offs among different and contrasting attributes (like timeliness, reliability, cost and performance) in dependable real time systems; development of a composability approach to adaptive fault tolerance based on FERT entities; preparation of a synthetic benchmark suite for adaptive hard real time systems and investigation of predictability under dynamic reconfiguration after faults.
Within the project, five papers have been presented at conferences and workshops. Moreover, a chapter of the book "Advances in Real time Systems", Prentice Hall, 1995, has been written by members of the working group.
Consiglio Nazionale delle Ricerche
Istituto di Elaborazione della Informazione
Via Santa Maria, 46
I - 56126 PISA, I
University of York, UK
University of Massachussets-Amherst, USA
Dr. Felicita Di Giandomenico
Tel: +39 50 593 443
Fax: +39 50 554 342
AFERT - EC-US041, May 1997
please address enquiries to the ESPRIT Information Desk
html version of synopsis by Nick Cook