  After carefully considering the scalability problem in Tor and exhaustively
evaluating related works on AS-level adversaries, the author proposes
ASmoniTor, which is an autonomous system monitor for mitigating correlation
attacks in the Tor network. In contrast to prior works, which often released
offline packets, including the source code of a modified Tor client and a
snapshot of the Internet topology, ASmoniTor is an online system that assists
end users with mitigating the threat of AS-level adversaries in a near
real-time fashion. For Tor clients proposed in previous works, users need to
compile the source code on their machine and continually update the snapshot of
the Internet topology in order to obtain accurate AS-path inferences. On the
contrary, ASmoniTor is an online platform that can be utilized easily by not
only technical users, but also by users without a technical background, because
they only need to access it via Tor and input two parameters to execute an
AS-aware path selection algorithm. With ASmoniTor, the author makes three key
technical contributions to the research against AS-level adversaries in the Tor
network. First, ASmoniTor does not require the users to initiate complicated
source code compilations. Second, it helps to reduce errors in AS-path
inferences by letting users input a set of suspected ASes obtained directly
from their own traceroute measurements. Third, the Internet topology database
at the back-end of ASmoniTor is periodically updated to assure near real-time
AS-path inferences between Tor exit nodes and the most likely visited websites.
Finally, in addition to its convenience, ASmoniTor gives users full control
over the information they want to input, thus preserving their privacy.
