Distributed breakout revisited

Distributed breakout algorithm (DBA) is an efficient method for solving distributed constraint satisfaction problems (CSP). Inspired by its potential of being an efficient, low-overhead agent coordination method for problems in distributed sensor networks, we study DBA's properties in this paper. We specifically show that on an acyclic graph of <i>n</i> nodes, DBA can find a solution in <i>O(n<sup>2</sup>)</i> synchronized distributed steps. This completeness result reveals DBA's superiority over conventional local search on acyclic graphs and implies its potential as a simple self-stabilization method for tree-structured distributed systems. We also show a worst case of DBA in a cyclic graph where it never terminates. To overcome this problem on cyclic graphs, we propose two stochastic variations to DBA. Our experimental analysis shows that stochastic DBAs are able to avoid DBA's worst-case scenarios and has similar performance as that of DBA.

[1]  M. Yokoo,et al.  Distributed Breakout Algorithm for Solving Distributed Constraint Satisfaction Problems , 1996 .

[2]  Eugene C. Freuder,et al.  The Complexity of Some Polynomial Network Consistency Algorithms for Constraint Satisfaction Problems , 1985, Artif. Intell..

[3]  Weixiong Zhang,et al.  Distributed Stochastic Search for Constraint Satisfaction and Optimization: Parallelism, Phase Transitions and Performance , 2002 .

[4]  Valmir Carneiro Barbosa,et al.  An introduction to distributed algorithms , 1996 .

[5]  Makoto Yokoo,et al.  The Distributed Constraint Satisfaction Problem: Formalization and Algorithms , 1998, IEEE Trans. Knowl. Data Eng..

[6]  Zhidong Deng,et al.  Distributed problem solving in sensor networks , 2002, AAMAS '02.

[7]  Paul Morris,et al.  The Breakout Method for Escaping from Local Minima , 1993, AAAI.

[8]  Stephen Fitzpatrick,et al.  An Experimental Assessment of a Stochastic, Anytime, Decentralized, Soft Colourer for Sparse Graphs , 2001, SAGA.

[9]  Peter van Beek,et al.  On the Conversion between Non-Binary and Binary Constraint Satisfaction Problems , 1998, AAAI/IAAI.

[10]  Marko Fabiunke,et al.  Parallel Distributed Constraint Satisfaction , 1999, PDPTA.

[11]  Shmuel Katz,et al.  Self-Stabilizing Distributed Constraint Satisfaction , 1999, Chic. J. Theor. Comput. Sci..

[12]  Peter van Beek,et al.  On the conversion between non-binary constraint satisfaction problems , 1998, AAAI 1998.

[13]  Makoto Yokoo,et al.  Distributed Constraint Satisfaction: Foundations of Cooperation in Multi-agent Systems , 2000 .