Salsa is a structured peer-to-peer system that is designed to perform robust and reliable lookups. It uses a distributed hash table based on hashes of the nodes' IP addresses to organize the nodes into groups. With a virtual tree structure, limited knowledge of other nodes is enough to route lookups throughout the system. The authors use redundancy and bounds checking when performing lookups to prevent malicious nodes from returning false information without detection. They show that their scheme prevents attackers from biasing lookups, while incurring moderate overheads, as long as the fraction of malicious nodes is less than 20%.