With the advent of Internet-enabled cellular phones, two-way pagers and other mobile PDAs, venders and portals are focusing on a platform-independent technology to efficiently provide the mobile users with the up-to-date Internet contents and services. The enabling network technology for being online over wireless anywhere is ready for prime time. The mobile computing and networking environment has achieved seamless integration with the wired Internet. However, the architecture of the enterprise application for mobile and multiband devices is still under construction within the portals and service providers due to the challenges of limited CPU, low memory, short power and special presentation requirement on the mobile devices. WAP (Wireless Application Protocol) is proposed and designed to provide the wireless applications with a scalable and extensible protocol stack to deliver the HTTP / TCP / IP-based Internet content to the mobile device through the wireless network. On the other hand, SMS (Short Message Service) provides the wireless portal with a legacy approach over the wireless networks. Either WAP or SMS provides an environment to build the wireless applications. Thus a scalable wireless portal architecture is needed to support the Internet contents and services on the mobile devices. This lecture introduces the WAP model and application environment as well as the SMS architecture and services followed by a proposal of a scalable multi-tier architecture for wireless portal (SMART).