Due to the dissemination of high speed DSL and FTTH, realtime streaming applications transmitting high quality audio and video data have been commonly used on the Internet. These applications usually have strict requirements on delay and packet loss. However, it is difficult to fully satisfy the requirements in general, since the end users cannot guarantee the streaming quality on the best-effort Internet. In this paper, we investigate an FEC (Forward Error Correction) function on DV streaming. We study the relation between network bandwidth and FEC recovery rate upon data transmission, and the receiver's play quality and FEC calculation cost. Our experimental results given on top of our testbed network show that the FEC function can provide the best possible streaming quality, without leading the further disruption of video and audio irrespective of the available network bandwidth.