The BG distributed simulation algorithm

Borowsky, Elizabeth; Gafni, Eli; Lynch, Nancy; Rajsbaum, Sergio

doi:10.1007/pl00008933

Cited by 116 publications

(200 citation statements)

References 23 publications

Supporting

Mentioning

200

Contrasting

Order By: Relevance

“…If there is a recent one (it is associated with a round greater than the round r start i at which p i has started simulating its current operation), p i keeps it in smin i (lines [8][9], and computes in last snap i the corresponding snapshot value of the shared memory (line 10). Finally, if p i observes that its last operation announced (that is identified est i [i]) appears in this vector, it returns last snap i (line 11).…”

Section: From Iris (Pr 3sx ) To the Read/write Model Equipped With 3s Xmentioning

confidence: 99%

“…An early approach towards this goal has been to derive direct simulations from one model to another; e.g., to show how to transform a protocol running in an asynchronous message passing model to one for a shared memory model [2], or from an asynchronous model to a synchronous model [3], or from a protocol tolerating some number of failures to one tolerating more failures [8]. A more recent approach has been to devise models of a higher level of abstraction, where results about various more specific models can be derived (e.g., [16,23,28]).…”

Section: Introductionmentioning

confidence: 99%

“…A major obstacle in the development of a theory of distributed computing is the wide variety of models that can be defined -many of which represent real systems -with combinations of parameters in both the (a)synchrony and failure dimensions [4,26,27]. Thus, an important line of research is concerned with finding ways of unifying results, impossibility techniques, and algorithm design paradigms of different models.An early approach towards this goal has been to derive direct simulations from one model to another; e.g., to show how to transform a protocol running in an asynchronous message passing model to one for a shared memory model [2], or from an asynchronous model to a synchronous model [3], or from a protocol tolerating some number of failures to one tolerating more failures [8]. A more recent approach has been to devise models of a higher level of abstraction, where results about various more specific models can be derived (e.g., [16,23,28]).…”

mentioning

confidence: 99%

See 2 more Smart Citations

The Iterated Restricted Immediate Snapshot Model

Rajsbaum¹,

Raynal

Travers

Lecture Notes in Computer Science

View full text Add to dashboard Cite

Abstract:In the Iterated Immediate Snapshot model (IIS ) the memory consists of a sequence of one-shot Immediate Snapshot (IS ) objects. Each IS object can be accessed with an operation that atomically writes a value and returns a snapshot of its contents. Each process can access each IS object at most once. Processes access the sequence of IS objects, one-by-one, asynchronously, in a wait-free manner; any number of processes can crash. It has been shown by Borowsky and Gafni and others that this model is very useful to study the usual read/write shared memory model. Its interest lies in the elegant recursive structure of its runs, hence of the ease to analyze it round by round. In a very interesting way, Borowsky and Gafni have shown that the IIS model and the read/write model are equivalent for the wait-free solvability of decision tasks.In this paper we extend the benefits of the IIS model to partially synchronous systems. Given a shared memory model enriched with a failure detector, what is an equivalent IIS model? The paper shows that an elegant way of capturing the power of a failure detector and other partially synchronous systems in the IIS model is by restricting appropriately its set of runs, giving rise to the Iterated Restricted Immediate Snapshot model (IRIS ).The benefit of the proposed approach is new results (including new proofs of existing results) when we consider the IRIS model instead of the equivalent read/write model enriched with a given failure detector directly. As a study case, the paper considers a system enriched with limited-scope accuracy failure detectors, where there is a cluster of processes such that eventually some correct process is eventually never suspected by any process in that cluster. The paper provides a new proof of the k-set agreement Herlihy and Penso's lower bound for shared memory system augmented with a limited-scope accuracy failure detector. The proof is based on an extension of the Borowsky-Gafni IIS simulation to encompass failure detectors, followed by a very simple topological argumentation.With the IRIS model we have succeeded in capturing the partial synchrony of a failure detector enriched system via a fully asynchronous, round by round system. We thus hope to have contributed to a better understanding of fault-tolerant distributed computing. Key-words:Algorithmic reduction, Asynchronous system, Distributed algorithm, Distributed Computability, Failure detectors, Fault-tolerance, Round-based computation, Shared memory, Topology. IntroductionA distributed model of computation consists of a set of n processes communicating through some medium (some form of message passing or shared memory), satisfying specific timing assumptions (process speeds and communication delays), and failure assumptions (their number and severity). A major obstacle in the development of a theory of distributed computing is the wide variety of models that can be defined -many of which represent real systems -with combinations of parameters in both the (a)synchrony and failure dimen...

show abstract

Section: From Iris (Pr 3sx ) To the Read/write Model Equipped With 3s Xmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

The Iterated Restricted Immediate Snapshot Model

Rajsbaum¹,

Raynal

Travers

Lecture Notes in Computer Science

View full text Add to dashboard Cite

show abstract

“…The variable r i is local to p i ; it denotes its current round number. As indicated in the Introduction, when considering distributed tasks (as formally defined in [8,20]), the IIS model and CARW n,t [0 < t < n] have the same computational power [7].…”

Section: The Iterated Immediate Snapshot (Iis) Modelmentioning

confidence: 99%

t-Resilient Immediate Snapshot Is Impossible

Delporte

Fauconnier

Rajsbaum³

et al. 2016

Structural Information and Communication Complexity

View full text Add to dashboard Cite

“…Robots can also converge in Euclidean space; see [28] for a recent treatment of a basic multi-dimensional robot convergence task tolerating Byzantine faults, including a discussion of applications to robots, distributed voting and optimization problems, as well as further related references. Various other *Correspondence: armando.castaneda@im.unam.mx 1 Instituto de Matemáticas, UNAM, Ciudad Universitaria, 04510 Mexico city, Mexico Full list of author information is available at the end of the article applications and specific robot convergence tasks appear in, e.g., [8,22,23,27,30].…”

Section: Introductionmentioning

confidence: 99%

Convergence and covering on graphs for wait-free robots

2018

View full text Add to dashboard Cite

The class of robot convergence tasks has been shown to capture fundamental aspects of fault-tolerant computability. A set of asynchronous robots that may fail by crashing, start from unknown places in some given space, and have to move towards positions close to each other. In this article, we study the case where the space is uni-dimensional, modeled as a graph G. In graph convergence, robots have to end up on one or two vertices of the same edge. We consider also a variant of robot convergence on graphs, edge covering, where additionally, it is required that not all robots end up on the same vertex. Remarkably, these two similar problems have very different computability properties, related to orthogonal fundamental issues of distributed computations: agreement and symmetry breaking. We characterize the graphs on which each of these problems is solvable, and give optimal time algorithms for the solvable cases. Although the results can be derived from known general topology theorems, the presentation serves as a self-contained introduction to the algebraic topology approach to distributed computing, and yields concrete algorithms and impossibility results.

show abstract

The BG distributed simulation algorithm

Cited by 116 publications

References 23 publications

The Iterated Restricted Immediate Snapshot Model

The Iterated Restricted Immediate Snapshot Model

t-Resilient Immediate Snapshot Is Impossible

Convergence and covering on graphs for wait-free robots

Contact Info

Product

Resources

About