Skip to main content
Log in

Speeding up distributed pseudo-tree optimization procedures with cross edge consistency to solve DCOPs

  • Published:
Applied Intelligence Aims and scope Submit manuscript

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.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16

Similar content being viewed by others

Notes

  1. Cross-edge Consistency is a new form of consistency introduced in this paper for pruning out those possible values for the variables in a DCOP which cannot possibly be part of a consistent solution.

  2. Throughout this paper, we consider agents and variables as interchangeable.

  3. A communication structure is a path along which DCOP message passing takes place.

  4. The work presented in [2] has shown that DFS traversal often leads to low-quality chain-like pseudo-trees with poor parallelism.

References

  1. Cabon B, De Givry S, Lobjois L, Schiex T, Warners JP (1999) Radio link frequency assignment. Constraints 4(1):79–89

    Article  Google Scholar 

  2. Chen Z, He Z, He C (2017) An improved dpop algorithm based on breadth first search pseudo-tree for distributed constraint optimization. Appl Intell 47(3):607–623

    Article  Google Scholar 

  3. Cheng KC, Yap RH (2005) Constrained decision diagrams. In: Proceedings of the national conference on artificial intelligence, vol 20. AAAI Press, MIT Press, 1999, Menlo Park, p 366

  4. Farinelli A, Rogers A, Petcu A, Jennings NR (2008) Decentralised coordination of low-power embedded devices using the max-sum algorithm. In: Proceedings of the 7th international joint conference on Autonomous agents and multiagent systems-Volume 2, International Foundation for Autonomous Agents and Multiagent Systems, pp 639–646

  5. Fioretto F, Le T, Yeoh W, Pontelli E, Son TC (2014) Improving dpop with branch consistency for solving distributed constraint optimization problems. In: International conference on principles and practice of constraint programming, Springer, pp 307–323

  6. Fioretto F, Yeoh W, Pontelli E (2017) A multiagent system approach to scheduling devices in smart homes. In: Proceedings of the 16th conference on autonomous agents and multiagent systems, International Foundation for Autonomous Agents and Multiagent Systems, pp 981–989

  7. Greenstadt R, Grosz B, Smith MD (2007) Ssdpop: improving the privacy of dcop with secret sharing. In: Proceedings of the 6th international joint conference on Autonomous agents and multiagent systems, ACM, pp 171

  8. Hirayama K, Yokoo M (1997) Distributed partial constraint satisfaction problem. In: International conference on principles and practice of constraint programming, Springer, pp 222–236

  9. Hirayama K, Yokoo M (2005) The distributed breakout algorithms. Artif Intell 161(1-2):89–115

    Article  MathSciNet  Google Scholar 

  10. de la Hoz E, Gimenez-Guzman JM, Marsa-Maestre I, Cruz-Piris L, Orden D (2017) A distributed, multi-agent approach to reactive network resilience. In: Proceedings of the 16th Conference on Autonomous Agents and MultiAgent Systems, International Foundation for Autonomous Agents and Multiagent Systems, pp 1044–1053

  11. Jain M, Taylor M, Tambe M, Yokoo M (2009) Dcops meet the real world: Exploring unknown reward matrices with applications to mobile sensor networks. In: Twenty-first international joint conference on artificial intelligence

  12. Kumar A, Petcu A, Faltings B (2008) H-dpop: Using hard constraints for search space pruning in dcop. In: AAAI, pp 325–330

  13. Maheswaran RT, Tambe M, Bowring E, Pearce JP, Varakantham P (2004) Taking dcop to the real world: Efficient complete solutions for distributed multi-event scheduling. In: Proceedings of the Third international joint conference on autonomous agents and multiagent systems-Volume 1, IEEE Computer Society, pp 310–317

  14. Modi PJ, Shen WM, Tambe M, Yokoo M (2005) Adopt: Asynchronous distributed constraint optimization with quality guarantees. Artif Intell 161(1-2):149–180

    Article  MathSciNet  Google Scholar 

  15. Netzer A, Grubshtein A, Meisels A (2012) Concurrent forward bounding for distributed constraint optimization problems. Artif Intell 193:186–216

    Article  MathSciNet  Google Scholar 

  16. Orden D, Gimenez-Guzman J, Marsa-Maestre I, de la Hoz E (2018) Spectrum graph coloring and applications to wi-fi channel assignment. Symmetry 10(3):65

    Article  Google Scholar 

  17. Petcu A, Faltings B (2005) A scalable method for multiagent constraint optimization. Tech rep

  18. Petcu A, Faltings B (2006) Odpop: an algorithm for open/distributed constraint optimization. In: AAAI, vol 6, pp 703–708

  19. Petcu A, Faltings B (2007) Mb-dpop: a new memory-bounded algorithm for distributed optimization. In: IJCAI, pp 1452–1457

  20. Petcu A, Faltings B, Parkes DC (2008) M-dpop: Faithful distributed implementation of efficient social choice problems. J Artif Intell Res 32:705–755

    Article  MathSciNet  Google Scholar 

  21. Schieber B, Vishkin U (1988) On finding lowest common ancestors: Simplification and parallelization. SIAM J Comput 17(6):1253–1262

    Article  MathSciNet  Google Scholar 

  22. Vinyals M, Rodriguez-Aguilar JA, Cerquides J (2009) Generalizing dpop: Action-gdl, a new complete algorithm for dcops. In: Proceedings of The 8th international conference on autonomous agents and multiagent systems-Volume 2, International Foundation for Autonomous Agents and Multiagent Systems, pp 1239–1240

  23. Yokoo M, Durfee EH, Ishida T, Kuwabara K (1998) The distributed constraint satisfaction problem: Formalization and algorithms. IEEE Transactions on knowledge and data engineering 10(5):673–685

    Article  Google Scholar 

  24. Zhang W, Wang G, Xing Z, Wittenburg L (2005) Distributed stochastic search and distributed breakout: properties, comparison and applications to constraint optimization problems in sensor networks. Artif Intell 161(1-2):55–87

    Article  MathSciNet  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Mashrur Rashik.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Rashik, M., Rahman, M.M., Khan, M.M. et al. Speeding up distributed pseudo-tree optimization procedures with cross edge consistency to solve DCOPs. Appl Intell 51, 1733–1746 (2021). https://doi.org/10.1007/s10489-020-01860-8

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10489-020-01860-8

Keywords

Navigation