Denial-of-Service (DoS) attacks has been threatening our evolving eCommerce and eServices on the Internet for years. Regarding today's stateless Internet environment, researchers have designed various schemes carrying additional information to providing information for defending packet flooding attacks, packet dropping attacks, and routing protocol attacks. We present a multifunctional scheme, the ICMP Caddie message scheme (iCaddie), which loads specialized ICMP messages with route information of randomly-selected IP packets, to support IP traceback, packet dropping detention, routing protocol protection, differential services as well as message authentication and authorization.