Asynchronous Forward-Checking on DisCSPs
نویسندگان
چکیده
A new search algorithm for solving distributed constraint satisfaction problems (DisCSPs) is presented. Agents assign variables sequentially, but perform forward checking asynchronously. The asynchronous forward-checking algorithm (AFC) is a distributed search algorithm that keeps one consistent partial assignment at all times. Forward checking is performed by sending copies of the partial assignment to all unassigned agents concurrently. The algorithm is described in detail and its correctness proven. An experimental comparison of AFC to Asynchronous BackTracking (ABT ), on randomly generated DisCSPs with different forms of communication is presented. AFC outperforms ABT on systems with a random message delay by a large factor on the harder instances of random DisCSPs. This result holds for both measures of performance, total run time in the form of computation steps and network load in the form of the total number of messages sent.
منابع مشابه
Asynchronous Inter-Level Forward-Checking for DisCSPs
We propose two new asynchronous algorithms for solving Distributed Constraint Satisfaction Problems (DisCSPs). The first algorithm, AFC-ng, is a nogood-based version of Asynchronous Forward Checking (AFC). The second algorithm, Asynchronous Inter-Level Forward-Checking (AILFC), is based on the AFC-ng algorithm and is performed on a pseudo-tree ordering of the constraint graph. AFC-ng and AILFC ...
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