Web-based applications offer a range of the benefits over traditional desktop applications; they are good for wide accessibility, platform independence, rich user experience, dynamic content, high scalability easy-to-share, and easy-to-use. This study proposes a web-based framework of multimedia support for collaborative editing. A transmission protocol that integrates operation transformation(OT) with the consideration of transmission for large media file was also proposed. The proposed mechanism has advantages for integration of existed OT-based collaborative schemes. The storage requirement of collaborative systems is also reduced. We believe the proposed mechanism is usable for web-based collaborative applications.