Nearly all of the multimedia streaming applications running on the Internet today are basically configured or designed for 2D video broadcast or multicast purposes. With its tremendous flexibility, MPEG-4 interactive clientserver applications are expected to play an important role in online multimedia services in the future. This paper presents the initial design and implementation of a transport infrastructure for an IP based network that will support a clientserver system which enables end users to: 1) author their own MPEG-4 presentations, 2) control the delivery of the presentation, and 3) interact with the system to make changes to the presentation in real time. A specification for the overall system structure is outlined. Some initial thoughts on the server and client system designs, the data transport component, QoS provisioning, and the control plane necessary to support an interactive application are described.