The design of digital video communications systems is a very active research area. Due to the stringent requirement of video and characteristics of networking technologies, the provisioning of control mechanisms guaranteeing a certain level of service is essential for the success of distributed video applications. In this paper, we study the use of different schemes for the robust transmission of MPEG-2 video over ATM networks. We compare error-resilience performance of two data-partitioning schemes for MPEG-2 bit stream transmitted over ATM networks where two layers of priority traffic are supported with different cell discarding schemes. The effectiveness of the different control mechanisms is quantitatively evaluated in terms of cells loss rates, end-to-end delay and cell loss distributions. Our results show that the use of control mechanisms at various levels of the protocol stack is essential for the deployment of error resilient video applications.