  Ever since the introduction of the internet, it has been void of any privacy.
The majority of internet traffic currently is and always has been unencrypted.
A number of anonymous communication overlay networks exist whose aim it is to
provide privacy to its users. However, due to the nature of the internet, there
is major difficulty in getting these networks to become both decentralized and
anonymous. We list reasons for having anonymous networks, discern the problems
in achieving decentralization and sum up the biggest initiatives in the field
and their current status. To do so, we use one exemplary network, the Tor
network. We explain how Tor works, what vulnerabilities this network currently
has, and possible attacks that could be used to violate privacy and anonymity.
The Tor network is used as a key comparison network in the main part of the
report: a tabular overview of the major anonymous networking technologies in
use today.
