Computer Science Department
School of Computer Science, Carnegie Mellon University
RPT: Re-architecting Loss Protection
Dongsu Han, Ashok Anand*, Aditya Akella*, Srinivasan Seshan
Many types of time-critical communication occur in today's networks. However, providing reliability or robustness to such transfers is often challenging. Retransmission-based schemes can violate timing constraints, and redundancy-based FEC schemes impose significant bandwidth overhead and are difficult to tune.
In light of recent advances in content-aware networking, we argue that redundancy-based approaches need to be re-engineered. Content-aware networks allow the overhead of redundancy to be made very small, if the redundancy is introduced in a way that the network can understand. Based on this insight, we propose redundant packet transmission (RPT), a new loss protection scheme for content-aware networks. Using redundant video streaming (RS) as an example, we show that our approach, unlike FEC, provides low latency communications with a high degree of robustness and is insensitive to parameter selection. We tackle practical issues, such as minimizing the impact on other traffic and the network. Furthermore, we show that RPT provides a simple and general mechanism for application-specific timing control and flow prioritization.