In a recent VoD application, a stationary VoD server delivers video stream to a mobile device, particularly PDA, over wireless. Typically, the sending rate at the server is faster than the playback rate at a handheld device. Therefore, it can't receive streaming video as possible as the sending rate even if there is no congestion and extremely low BER over wireless. Our objective is to develop a simple cost effective rate control scheme using a buffer level at a mobile device. We classify the buffer at a mobile device into three distinct states depending on its level (occupancy). For each of these states a different rate control scheme is formulated. Since the sending rate increases as the inter-packet delay (IPD) at the sender decreases, we vary IPD to control the rate with its state. Adjustable parameters used in our proposed method are calibrated using our empirical results. These measurements were carried out on a test-bed which reproduces a real prototype of the wired-cum-wireless topology.
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