We study the problem of reliably searching for resources in untrusted peer-to-peer networks, where a significant portion of the participating network nodes may act maliciously to subvert the search process. We present a new method called Halo for performing redundant searches over a distributed hash table (DHT) structure to achieve high integrity and availability levels without affecting the storage and communication complexities of the underlying DHT. Other schemes for redundant searches have proposed new or modified DHTs with increased storage requirements at nodes, requiring modifications at all nodes in the network. In contrast, Halo aims to serve as a middleware component, making “black-box” calls of the underlying primitive search operation to eventually provide a new composite search operation of higher assurance. We apply this concept to the popular and well-studied DHT Chord, and demonstrate the efficiency and security of our approach though analytical modeling and si...