  Nodes in route-restricted overlays have an immutable set of neighbors,
explicitly specified by their users. Popular examples include payment networks
such as the Lightning network as well as social overlays such as the Dark
Freenet. Routing algorithms are central to such overlays as they enable
communication between nodes that are not directly connected. Recent results
show that algorithms based on spanning trees are the most promising provably
efficient choice. However, all suggested solutions fail to address how
distributed spanning tree algorithms can deal with active denial of service
attacks by malicious nodes. In this work, we design a novel self-stabilizing
spanning tree construction algorithm that utilizes cryptographic signatures and
prove that it reduces the set of nodes affected by active attacks. Our
simulations substantiate this theoretical result with concrete values based on
real-world data sets. In particular, our results indicate that our algorithm
reduces the number of affected nodes by up to 74% compared to state-of-the-art
attack-resistant spanning tree constructions.
