Dynamic Ordering for Asynchronous Backtracking on DisCSPs

An algorithm that performs asynchronous backtracking on distributed $$CSPs$$, with dynamic ordering of agents is proposed, $$ABT\_DO$$. Agents propose reorderings of lower priority agents and send these proposals whenever they send assignment messages. Changes of ordering triggers a different computation of $$Nogoods$$. The dynamic ordered asynchronous backtracking algorithm uses polynomial space, similarly to standard $$ABT$$. The $$ABT\_DO$$ algorithm with three different ordering heuristics is compared to standard $$ABT$$ on randomly generated $$DisCSPs$$. A Nogood-triggered heuristic, inspired by dynamic backtracking, is found to outperform static order $$ABT$$ by a large factor in run-time and improve the network load.

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