Near-optimal distributed dominating set in bounded arboricity graphs

We describe a simple deterministic O( ε ^-1logΔ ) round distributed algorithm for (2α +1)(1 + ε ) approximation of minimum weighted dominating set on graphs with arboricity at most α . Here Δ denotes the maximum degree. We also show a lower bound proving that this round complexity is nearly optimal even for the unweighted case, via a reduction from the celebrated KMW lower bound on distributed vertex cover approximation (Kuhn et al. in JACM 63:116, 2016). Our algorithm improves on all the previous results (that work only for unweighted graphs) including a randomized O(α ^2) approximation in O(log n) rounds (Lenzen et al. in International symposium on distributed computing, Springer, 2010), a deterministic O(αlogΔ ) approximation in O(logΔ ) rounds (Lenzen et al. in international symposium on distributed computing, Springer, 2010), a deterministic O(α ) approximation in O(log ^2 Δ ) rounds (implicit in Bansal et al. in Inform Process Lett 122:21–24, 2017; Proceeding 17th symposium on discrete algorithms (SODA), 2006), and a randomized O(α ) approximation in O(αlog n) rounds (Morgan et al. in 35th International symposiumon distributed computing, 2021). We also provide a randomized O(αlogΔ ) round distributed algorithm that sharpens the approximation factor to α (1+o(1)) . If each node is restricted to do polynomial-time computations, our approximation factor is tight in the first order as it is NP-hard to achieve α - 1 - ε approximation (Bansal et al. in Inform Process Lett 122:21-24, 2017).