Compact routing with slack in low doubling dimension

Abstract

We consider the problem of compact routing with slack in networks of low doubling dimension. Namely, we seek name-independent routing schemes with (1+e) stretch and polylogarithmic storage at each node: since existing lower bound precludes such a scheme, we relax our guarantees to allow for (i) a small fraction of nodes to have large storage, say size of O(n log n) bits, or (ii) a small fraction of source-destination pairs to have larger, but still constant, stretch.In this paper, given any constant e ∈ (0,1), any δ ∈ Θ(1/ polylog n) and any connected edge-weighted undirected graph G with doubling dimension α ∈ O(log log n) and arbitrary node names, we present 1. a (1+e)-stretch name-independent routing scheme for G with polylogarithmic packet header size, and with (1-δ)n nodes storing polylogarithmic size routing tables each and the remaining δn nodes storing O(nlog n)-bit routing tables each.2. a name-independent routing scheme for G with polylogarithmic storage and packet header size, and with stretch (1+e) for (1-α n source nodes and (9+e) for the remaining α n source nodes..These results are to be contrasted with our lower bound from PODC 2006, where we showed that stretch 9 is asymptotically optimal for name-independent compact routing schemes in networks of constant doubling dimension.