Comparison of Multimedia Transport Schemes over Markovian Wireless Channels
Contemporary wireless networks drop all corrupted packets at the receivers. Such a strategy adversely affects multimedia applications which have stringent throughput and delay constraints. Recently, a header estimation scheme was proposed to reduce packet drops at wireless receivers [1], [2]. These corrupted packets are recovered using FEC, which incurs lesser delay and bandwidth wastage than retransmissions. In this paper, we derive lower bounds on the excepted FEC redundancy required by ideal header estimation, UDP and UDP-Lite over an arbitrary-order Markov wireless channel. We show that under realistic wireless channel conditions, header estimation always requires lesser redundancy than UDP and UDP-Lite. We then propose a practical minimum distance decoding (MDD) header estimation scheme, which is receiver-based, low complexity and highly accurate. Trace-driven wireless video simulations demonstrate that MDD header estimation requires significantly lesser FEC redundancy and renders better video quality than existing schemes.