Casey, you were correct. Without NATing, the problem does not exist. However, there is nothing 'sophisticated' about the NAT setup. And, as the captures illustrate, the nmap UDP packet passes through the router in the expected fashion. JMcLaren - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html