Distributed error confinement

We initiate the study of error confinement in distributed applications, where the goal is that only nodes that were directly hit by a fault may deviate from their correct external behavior, and only temporarily. The external behavior of all other nodes must remain impeccable, even though their internal state may be affected. Error confinement is impossible if an adversary is allowed to inflict arbitrary transient faults on the system, since the faults might completely wipe out input values. We introduce a new fault tolerance measure we call agility, which quantifies the strength of an algorithm that disseminates information against state corrupting faults. We study the basic problem of broadcast, and propose algorithms that guarantee error confinement with optimal agility to within a constant factor. These algorithms can serve as building blocks in more general reactive systems. Previous results in exploring locality in reactive systems were not error confined, and relied on restricti...

• Type: Journal
• Year: 2010
• Where: TALG
• Authors: Yossi Azar, Shay Kutten, Boaz Patt-Shamir
• Keywords: Error Confinement, External Behavior, Natural Language Processing, Reactive Systems, TALG 2010