Hashed Patricia Trie: Efficient Longest Prefix Matching in Peer-to-Peer Systems

Abstract

The design of efficient search structures for peer-to-peer systems has attracted a lot of attention in recent years. In this paper we address the problem of longest prefix matching and present an efficient data structure called hashed Patricia trie. Our hashed Patricia trie supports Prefixsearch(x) and Insert(x) in $\mathcal O(\log \left|x\right|)$ hash table accesses and Delete(x) in $\mathcal O(1)$ hash table accesses when |x| is the number of bits used to encode x. That is the costs only depend on |x| and not the size of the data structure. The hash table accesses may be realized by any distributed hash table (DHT).