Seminars at the Faculty of Informatics

Online Testing of Distributed Systems

The Faculty of Informatics is pleased to announce a seminar given by Dejan Kostic

DATE: Thursday, February 9th 2012

PLACE: USI Università della Svizzera italiana, room SI-006, Informatics building (Via G. Buffi 13)

TIME: 13.30


Distributed systems form the foundation of our society's infrastructure. Complex distributed protocols and algorithms are used in enterprise storage systems, distributed databases, large-scale planetary systems, and the Internet itself. Errors in these protocols translate to denial of service to some clients, potential loss of data, and monetary losses. It is notoriously difficult to make distributed systems reliable. This becomes even harder in the case of the widely-deployed systems that are heterogeneous (multiple implementations) and federated (multiple administrative entities).  We argue that a key step in making these systems reliable is in detecting deviations from the desired behavior by predicting future system behavior in a novel way - by running the code itself from current state using either model checking, or a variant of symbolic execution. The systems we have built materialize this vision. For example, CrystalBall uses live model checking and execution steering to guard against unknown programming faults (bugs). DiCE goes one step further in that it detects faults in heterogeneous, federated distributed systems in which it is impossible to retrieve code, state, or configuration files from other participants. We demonstrate the ease of integrating DiCE with a BGP router and a DNS server, the building blocks of two vital services in the Internet. Our evaluation shows that our systems quickly and successfully detect three important classes of faults, resulting from configuration mistakes, policy conflicts and programming errors.


Dejan Kostić obtained his Ph.D. in Computer Science at the Duke University, under Amin Vahdat. He spent the last two years of his studies and a brief stay as a postdoctoral scholar at the University of California, San Diego. He received his Master of Science degree in Computer Science from the University of Texas at Dallas, and his Bachelor of Science degree in Computer Engineering and Information Technology from the University of Belgrade (ETF), Serbia. In January 2006, he started as a tenure-track assistant professor at the School of Computer and Communications Sciences at EPFL (Ecole Polytechnique Fédérale de Lausanne), Switzerland. In 2010, he received a European Research Council (ERC) Starting Investigator Award. His interests include Distributed Systems, Computer Networks, Operating Systems, and Mobile Computing.

HOST: Prof. Fernando Pedone

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