Exploiting the Path Propagation Time Differences in Multipath Transmission with FEC

TL;DR

This paper introduces a novel packet scheduling method called 'Spread' that leverages path propagation time differences in multipath FEC transmission, significantly reducing loss rates and delays in delay-sensitive data streaming.

Contribution

It proposes and evaluates a new scheduling approach that exploits path delay differences to enhance multipath FEC performance beyond existing solutions.

Findings

Spread achieves 2-5 times reduction in effective loss rate.

It significantly decreases delays and jitter in delay-sensitive streams.

The method outperforms state-of-the-art solutions in simulations.

Abstract

We consider a transmission of a delay-sensitive data stream from a single source to a single destination. The reliability of this transmission may suffer from bursty packet losses - the predominant type of failures in today's Internet. An effective and well studied solution to this problem is to protect the data by a Forward Error Correction (FEC) code and send the FEC packets over multiple paths. In this paper we show that the performance of such a multipath FEC scheme can often be further improved. Our key observation is that the propagation times on the available paths often significantly differ, typically by 10-100ms. We propose to exploit these differences by appropriate packet scheduling that we call `Spread'. We evaluate our solution with a precise, analytical formulation and trace-driven simulations. Our studies show that Spread substantially outperforms the state-of-the-art solutions. It typically achieves two- to five-fold improvement (reduction) in the effective loss rate. Or conversely, keeping the same level of effective loss rate, Spread significantly decreases the observed delays and helps fighting the delay jitter.