A Framework for Monitoring Net Neutrality

Abstract

Internet service providers can discriminate traffic in certain ways, e.g., by the used protocol or application. This leads to advantages for providers, but also harms the freedom and innovation in the Internet. However, ISPs currently use a variety of technical measures. Some can be seen as questionable regarding net neutrality { an important topic in legal and economic discussions. These methods are often neither technically identified nor continuously monitored, which prevents an informed discussion about the legitimacy of such methods. In this paper, we design and implement an open-source framework for monitoring such techniques within a country. Compared to other projects, we are able to fully control the client and server endpoint and therefore analyze network behavior in depth. We implement 17 different metrics that cover a wide range of the network spectrum. We test basic network features on transport layer as well as specific application layer protocols. We then use this frame- work to monitor five different Internet products in Austria over the time span of more than one year. We evaluate the results from our three measurement periods of three months each and find different questionable methods in place. This includes e.g., middleboxes used for various protocols, mon- etization of DNS results and different behavior for special DNS queries. However, many metrics show that currently no questionable techniques are used.