I/O efficient dynamic data structures for longest prefix queries

We present an efficient data structure for finding the longest prefix of a query string p in a dynamic database of strings. When the strings are IP-addresses then this is the IP-lookup problem. bur data structure is I/O efficient. It supports a query with a string p using O(log(B)(n) + \p\/B) I/O operations, where B is the size of a disk block. It also supports an insertion and a deletion of a string p with the same number of I/O's. The size of the data structure is linear in the size of the database and the running time of each operation is O(log(n) + \p\).