1. A method for updating a forwarding table in a packet network device, comprising: defining a first plurality of routing policies for inclusion into a first sequentially numbered list of routing policies; defining a second plurality of routing policies for inclusion into an ordered prefix list that includes a second sequentially numbered list of routing policies, at least some of the second plurality of routing policies including a non-contiguous IP prefix mask; building a radix tree structure with information included in the first sequentially numbered list of routing policies; using IP prefix information included in an IP prefix to search the radix tree structure to identify a lowest sequence number routing policy in the radix tree structure that best matches the IP prefix information; using the IP prefix information in the IP prefix to search the ordered prefix list to identify a lowest sequence number routing policy in the ordered prefix list that best matches the IP prefix information; comparing the lowest sequence number routing policy in the ordered prefix list with the lowest sequence number routing policy in the radix tree structure to identify a routing policy with the overall lowest sequence number; and updating the forwarding table with the IP prefix information if the routing policy with the overall lowest sequence number includes an instruction to permit the IP prefix.