A multi-CDN request routing strategy

Abstract

In this thesis, we design and implement a multi-CDN request routing strategy for Spotify’s audio files. Through A/B testing, we show that our strategy improves median download latency compared to Spotify’s existing routing strategy. Our strategy groups Spotify’s users by autonomous system number and country, and uses a linear programming model on download latency log messages to generate routing weights on a group-by-group basis. Our linear programming model generates routing weights with the goal of minimising request latencies, while also preserving a number of traffic volume constraints.