How to Network Delay-Sensitive Applications

In this paper we study design principles of congestion control supporting low-latency applications. In this regard, we show the attractiveness of a bounded-delay model satisfying latency constraints instead of optimizing them. Under this model, we propose two transformations automatically generating policies with finite buffers from policies with infinite buffers while keeping performance guarantees. These transformations allow us to reconsider design principles of congestion control, in particular, avoiding delivery of unnecessary traffic. We study the impact of different policy properties on required buffer sizing and at the extreme case define potential ways to build reliable transports without retransmissions. In addition, we build a taxonomy of management policies for various types of extra knowledge and propose another transformation kind constructing policies that optimize weighted goodput from policies optimizing throughput while keeping performance guarantees. Our analytic results are supported by extensive evaluations demonstrating attractiveness of the proposed design principles.