A Survey of Network Traffic Anonymisation Techniques and Implementations

\ Many networking research activities are dependent on the availability of network captures. Even outside academic research, there is a need for sharing network captures to cooperate on threat assessments or for debugging. However, most network captures cannot be shared due to privacy concerns. Anonymisation of network captures has been a subject of research for quite some time, and many different techniques exist. In this article, we present an overview of the currently available techniques and implementations for network capture anonymisation. There have beenmany advances in the understanding of anonymisation and cryptographic methods, which have changed the perspective on the effectiveness of many anonymisation techniques. However, these advances, combined with the increase of computational abilities, may have also made it feasible to perform anonymisation in real time. This may make it easier to collect and distribute network captures both for research and for other applications. This article surveys the literature over the period of 1998-2017 on network traffic anonymisation techniques and implementations. The aim is to provide an overview of the current state of the art and to highlight how advances in related fields have shed new light on anonymisation and pseudonimisation methodologies. The few currently maintained implementations are also reviewed. Last, we identify future research directions to enable easier sharing of network traffic, which in turn can enable new insights in network traffic analysis.