To improve the robustness of video transmission over heterogeneous wireless network various error resilient tools are deployed. The impact of bit errors on the perceived video quality depends on several factors, such as error resilience of the data format, error concealment mechanism used and characteristics of the bit error pattern. In this paper the impact of bit error is analyzed and various error resilient tools implemented at the transmitter side, at the receiver and the ones requiring interactive feedback on dynamic channel conditions are discussed. The paper also covers a few cross layer optimization techniques. © 2011 IEEE.