This figure shows a partitioned directory. Server A holds a tree with dc=com at the root, dc=acme as the root of a subtree that includes c=us, c=uk, and c=au. Server B likewise holds a tree with dc=com at the root, dc=acme as the root of a subtree that includes c=us, c=uk, and c=au. However, on Server B, only c=au is a replicated naming context. Both c=us and c=uk are knowledge references pointing back to those naming contexts on Server A.