Montra: A large-scale DHT traffic monitor

This paper presents a new technique, called Montra, for accurately capturing traffic in a widely deployed DHT. The basic idea is to make the traffic monitors minimally visible to participating peers to avoid disruption in the system. We describe how Montra leverages the required redundancy in published content and routing to minimize disruption of the system. Validations of Montra over two widely deployed DHTs, namely Kad and Azureus, show that it can accurately capture more than 90% of traffic destined to monitored peers. Furthermore, the lightweight nature of Montra allows it to monitor a large number of peers with a moderate amount of resources. We use Montra to characterize several aspects of traffic in our two target DHTs.