Content-aware selective reliability for DCCP video streaming

The growing use of real-time video in wireless networks, where loss rates are high yet bandwidth and CPU power of receivers can be scarce, calls for new methods to maintain good quality when packets are dropped. These methods should ideally only involve the sender and avoid increasing the amount of data sent across the network. We introduce a scheme that satisfies these requirements by selectively retransmitting only the most important packets in case of loss based on the video content at macroblock granularity. In a Linux implementation using the DCCP protocol, we show that our mechanism outperforms content-unaware retransmission strategies such as earliest-first.