English
Related papers

Related papers: Almost Global Problems in the LOCAL Model

200 papers

We present a complete classification of the deterministic distributed time complexity for a family of graph problems: binary labeling problems in trees. These are locally checkable problems that can be encoded with an alphabet of size two…

Distributed, Parallel, and Cluster Computing · Computer Science 2020-02-19 Alkida Balliu , Sebastian Brandt , Yuval Efron , Juho Hirvonen , Yannic Maus , Dennis Olivetti , Jukka Suomela

In this work, we give a unifying view of locality in four settings: distributed algorithms, sequential greedy algorithms, dynamic algorithms, and online algorithms. We introduce a new model of computing, called the online-LOCAL model: the…

Data Structures and Algorithms · Computer Science 2022-11-15 Amirreza Akbari , Navid Eslami , Henrik Lievonen , Darya Melnyk , Joona Särkijärvi , Jukka Suomela

In this work, we present a fast distributed algorithm for local potential problems: these are graph problems where the task is to find a locally optimal solution where no node can unilaterally improve the utility in its local neighborhood…

Distributed, Parallel, and Cluster Computing · Computer Science 2026-02-20 Alkida Balliu , Thomas Boudier , Francesco d'Amore , Fabian Kuhn , Dennis Olivetti , Gustav Schmid , Jukka Suomela

Common definitions of the "standard" LOCAL model tend to be sloppy and even self-contradictory on one point: do the nodes update their state using an arbitrary function or a computable function? So far, this distinction has been safe to…

Distributed, Parallel, and Cluster Computing · Computer Science 2026-02-26 Antonio Cruciani , Avinandan Das , Massimo Equi , Henrik Lievonen , Diep Luong-Le , Augusto Modanese , Jukka Suomela

By prior work, we have many results related to distributed graph algorithms for problems that can be defined with local constraints; the formal framework used in prior work is locally checkable labeling problems (LCLs), introduced by Naor…

Distributed, Parallel, and Cluster Computing · Computer Science 2024-07-09 Alkida Balliu , Mohsen Ghaffari , Fabian Kuhn , Augusto Modanese , Dennis Olivetti , Mikaël Rabie , Jukka Suomela , Jara Uitto

In this paper, we present the first known example of a locally checkable labeling problem (LCL) that admits asymptotic distributed quantum advantage in the LOCAL model of distributed computing: our problem can be solved in $O(\log n)$…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-04-08 Alkida Balliu , Filippo Casagrande , Francesco d'Amore , Massimo Equi , Barbara Keller , Henrik Lievonen , Dennis Olivetti , Gustav Schmid , Jukka Suomela

Locally checkable labeling problems (LCLs) form the foundation of the modern theory of distributed graph algorithms. First introduced in the seminal paper by Naor and Stockmeyer [STOC 1993], these are graph problems that can be described by…

Distributed, Parallel, and Cluster Computing · Computer Science 2026-02-23 Antonio Cruciani , Avinandan Das , Alesya Raevskaya , Jukka Suomela

The Local Computation Algorithm (LCA) model is a popular model in the field of sublinear-time algorithms that measures the complexity of an algorithm by the number of probes the algorithm makes in the neighborhood of one node to determine…

Data Structures and Algorithms · Computer Science 2021-12-06 Sebastian Brandt , Christoph Grunau , Václav Rozhoň

An impressive recent line of work has charted the complexity landscape of distributed graph algorithms. For many settings, it has been determined which time complexities exist, and which do not (in the sense that no local problem could have…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-05-28 Nicolas Bousquet , Laurent Feuilloley , Sébastien Zeitoun

Many graph problems are locally checkable: a solution is globally feasible if it looks valid in all constant-radius neighborhoods. This idea is formalized in the concept of locally checkable labelings (LCLs), introduced by Naor and…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-04-12 Alkida Balliu , Juho Hirvonen , Christoph Lenzen , Dennis Olivetti , Jukka Suomela

Over the past 30 years numerous algorithms have been designed for symmetry breaking problems in the LOCAL model, such as maximal matching, MIS, vertex coloring, and edge-coloring. For most problems the best randomized algorithm is at least…

Computational Complexity · Computer Science 2016-04-07 Yi-Jun Chang , Tsvi Kopelowitz , Seth Pettie

The problem of coloring the edges of an $n$-node graph of maximum degree $\Delta$ with $2\Delta - 1$ colors is one of the key symmetry breaking problems in the area of distributed graph algorithms. While there has been a lot of progress…

Distributed, Parallel, and Cluster Computing · Computer Science 2020-02-26 Alkida Balliu , Fabian Kuhn , Dennis Olivetti

Consider a graph problem that is locally checkable but not locally solvable: given a solution we can check that it is feasible by verifying all constant-radius neighborhoods, but to find a solution each node needs to explore the input graph…

Distributed, Parallel, and Cluster Computing · Computer Science 2020-02-19 Will Rosenbaum , Jukka Suomela

In this work we introduce the graph-theoretic notion of mendability: for each locally checkable graph problem we can define its mending radius, which captures the idea of how far one needs to modify a partial solution in order to "patch a…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-09-15 Alkida Balliu , Juho Hirvonen , Darya Melnyk , Dennis Olivetti , Joel Rybicki , Jukka Suomela

While obtaining optimal algorithms for the most important problems in the LOCAL model has been one of the central goals in the area of distributed algorithms since its infancy, tight complexity bounds are elusive for many problems even when…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-05-06 Sebastian Brandt , Ananth Narayanan

Locally Checkable Labeling (LCL) problems are graph problems in which a solution is correct if it satisfies some given constraints in the local neighborhood of each node. Example problems in this class include maximal matching, maximal…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-08-22 Alkida Balliu , Sebastian Brandt , Manuela Fischer , Rustam Latypov , Yannic Maus , Dennis Olivetti , Jara Uitto

We study the awake complexity of graph problems that belong to the class O-LOCAL, which includes a subset of problems solvable by sequential greedy algorithms, such as $(\Delta+1)$-coloring and maximal independent set. It is known from…

Distributed, Parallel, and Cluster Computing · Computer Science 2024-11-26 Alkida Balliu , Pierre Fraigniaud , Dennis Olivetti , Mikaël Rabie

We study \emph{local computation algorithms (LCAs)} for constructing spanning trees. In this setting, the goal is to locally determine, for each edge $ e \in E $, whether it belongs to a spanning tree $ T $ of the input graph $ G $, where $…

Data Structures and Algorithms · Computer Science 2026-02-10 Pan Peng , Yuyang Wang

The {Congested Clique} is a distributed-computing model for single-hop networks with restricted bandwidth that has been very intensively studied recently. It models a network by an $n$-vertex graph in which any pair of vertices can…

Distributed, Parallel, and Cluster Computing · Computer Science 2018-02-21 Leonid Barenboim , Victor Khazanov

We study the complexity of locally checkable labeling (LCL) problems on $\mathbb{Z}^n$ from the point of view of descriptive set theory, computability theory, and factors of i.i.d. Our results separate various complexity classes that were…

Logic · Mathematics 2025-05-08 Katalin Berlow , Anton Bernshteyn , Clark Lyons , Felix Weilacher