OSDI 2000 Abstract
Proactive Recovery in a
Byzantine-Fault-Tolerant System
Miguel Castro and Barbara Liskov, MIT
Abstract
This paper describes an asynchronous state-machine replication system that tolerates Byzantine faults, which can be
caused by malicious attacks or software errors. Our system is the first to recover Byzantine-faulty replicas proactively
and it performs well because it uses symmetric rather than public-key cryptography for authentication. The recovery
mechanism allows us to tolerate any number of faults over the lifetime of the system provided fewer than 1/3 of the
replicas become faulty within a window of vulnerability that is small under normal conditions. The window may
increase under a denial-of-service attack but we can detect and respond to such attacks. The paper presents results of
experiments showing that overall performance is good and that even a small window of vulnerability has little impact
on service latency.
|