Method and apparatus for building and using multi-dimensional index trees for multi-dimensional data objects

Abstract

A method and apparatus are provided for building a searchable multi-dimensional index tree that indexes a plurality of data objects. In one aspect of the invention, the index tree divides dataspace into three subspaces and indexes the data objects using a single dimension. If too many data objects map to the same point in that dimension, the dimension is switched to a new dimension of the data object and the data object is indexed using the new dimension. A split node having a split value is used to keep track of the indexing. In another aspect of the invention, the index tree divides dataspace into two subspaces, and equal bits are used in the split nodes to track the content of the data objects in the subspaces. If too many data objects sharing the same key within the same dimension map to a single point, then the dimension is switched to a new dimension and the data objects are indexed using the new dimension. Also disclosed is the multi-dimensional index tree itself as well as a router that uses the multi-dimensional index tree of the present invention to provide packet classification functions.