Monitoring Approaches For Anonymous Environments: The I2P Network


Anonymous communications are growing extremely fast: the Tor network has
tripled its user-base in the last year while the I2P anonymous network has
doubled its user-base in the last year. As more and more users are
employing anonymous networks in a daily basis, we need to understand and
determinate what these anonymous networks are used for. We focus on the
understanding of anonymous environments through extensive monitoring. We
designed and deployed a distributed architecture for the anonymous I2P
network. The I2P network is particularly challenging because it is a
closed network, in the sense that there are neither exit nodes nor exit
points and all traffic remains within the network boundaries. Therefore,
we need to deploy several in-network probes so as to gather network
metadata. We characterise the I2P network, targeting the entire anonymous
environment and its anonymous services. We consider different aspects of
the network, such as the number of users, their characteristics as well as
the number of anonymous services available. Through long-term measurements
on the network and along with different correlation analyses, we are able
to characterise a small group of users using a specific anonymous service,
such as the users from a particular city performing anonymous
file-sharing.