We consider router tables comprised of n pairs of tuples of the form (r,a), where r is a range of destination addresses matched by the tuple. The set of ranges in the table is conflict free. We develop a data structure, which employs priority-search trees as well as red-black trees, to represent the router table. This data structure permits us to perform each of the operations insert, delete, and find the tuple with most-specific matching-range for a given destination address in O(log n) time each. The insert and delete operations preserve the conflict-free property of the set of tuples. Our data structure represents the first O(log n) data structure for dynamic router tables with ranges. Experimental results also are presented.