Speeding up distributed pseudo-tree optimization procedures with cross edge consistency to solve DCOPs
File(s)1909.06537.pdf (640.19 KB)
Accepted version
OA Location
Author(s)
Type
Journal Article
Abstract
The Distributed Pseudo-tree Optimization Procedure (DPOP) is a well-known message passing algorithm that provides optimal solutions to Distributed Constraint Optimization Problems (DCOPs) in cooperative multi-agent systems. However, the traditional DCOP formulation does not consider constraints that must be satisfied (hard constraints), rather it concentrates only on constraints that place no restriction on satisfaction (soft constraints). This is a serious shortcoming as many real-world applications involve both types of constraints. Traditional DPOP algorithms are not able to benefit from the existence of hard constraints, where an additional calculation is required to handle such constraints. This results in longer runtimes. Thus scalability remains an issue. Additionally, in the standard DPOP, the agents are arranged as a Depth First Search (DFS) pseudo-tree, but recent work has shown that the construction of pseudo-trees in this way often leads to chain-like communication structures that greatly impair the algorithm’s performance. To address these issues, we develop an algorithm that speeds up the DPOP algorithm by reducing the size of the messages exchanged and increases parallelism in the pseudo tree. For this purpose, initially, we improve the path for exchanging messages. Next, we introduce a new form of constraint propagation, which we call cross-edge consistency. Our theoretical evaluation shows that our proposed algorithm is complete and correct. In empirical evaluations, our algorithm achieves a significant reduction in the runtime, ranging from 4% to 96%, compared to the state-of-the-art.
Date Issued
2021-03
Date Acceptance
2020-10-01
Citation
Applied Intelligence, 2021, 51, pp.1733-1746
ISSN
0924-669X
Publisher
Springer Science and Business Media LLC
Start Page
1733
End Page
1746
Journal / Book Title
Applied Intelligence
Volume
51
Copyright Statement
© Springer Science+Business Media, LLC, part of Springer Nature 2020. The final publication is available at Springer via https://link.springer.com/article/10.1007%2Fs10489-020-01860-8
Identifier
https://link.springer.com/article/10.1007%2Fs10489-020-01860-8
Subjects
Science & Technology
Technology
Computer Science, Artificial Intelligence
Computer Science
Multiagent system
Distributed problem solving
Distributed constraint optimization
DPOP
CONSTRAINT OPTIMIZATION
BREAKOUT
SEARCH
Artificial Intelligence & Image Processing
0801 Artificial Intelligence and Image Processing
Publication Status
Published
Date Publish Online
2020-10-10