Online multipath convolutional coding for real-time transmission

TL;DR

This paper introduces an online multipath convolutional coding scheme called Tetrys for real-time multimedia streaming, which outperforms traditional FEC methods in handling burst packet losses within multipath networks.

Contribution

It presents the Tetrys coding scheme and demonstrates its advantages over FEC in multipath streaming, along with an improved EMS algorithm and insights on redundancy traffic distribution.

Findings

Tetrys outperforms FEC in burst loss scenarios.

Modified EMS algorithm enhances packet recovery.

Using longer delay paths for repair packets improves performance.

Abstract

Most of multipath multimedia streaming proposals use Forward Error Correction (FEC) approach to protect from packet losses. However, FEC does not sustain well burst of losses even when packets from a given FEC block are spread over multiple paths. In this article, we propose an online multipath convolutional coding for real-time multipath streaming based on an on-the-fly coding scheme called Tetrys. We evaluate the benefits brought out by this coding scheme inside an existing FEC multipath load splitting proposal known as Encoded Multipath Streaming (EMS). We demonstrate that Tetrys consistently outperforms FEC in both uniform and burst losses with EMS scheme. We also propose a modification of the standard EMS algorithm that greatly improves the performance in terms of packet recovery. Finally, we analyze different spreading policies of the Tetrys redundancy traffic between available paths and observe that the longer propagation delay path should be preferably used to carry repair packets.