Anti-censorship applications are becoming
increasingly popular mean to circumvent Internet censorship, whether imposed by
governments seeking to control the flow of information available to their
citizens, or by parental figures wishing to shield their “parishioners” from
the dangers of the Internet, or in organizations trying to restrict the
Internet usage within their networking territory. Numerous applications are
readily accessible for the average user to aid-in bypassing Internet
censorship. Several technologies and techniques are associated with the
formation of these applications, whereas, each of these applications deploys
its unique mechanism to circumvent Internet censorship. Using anti-censorship
applications in the work environment can have a negative impact on the network,
leading to excessive degradation in the bandwidth, immense consumption of the
Internet data usage capacity and possibly open the door for security breaches.
Triumphing the war on anti-censorship applications has become more difficult to
achieve at the network level due to the rapid updates and the adopted new
technologies to circumvent censorship. In this study, a comprehensive overview
on Internet censorship and anti-censorship applications is provided by
analyzing Ultrasurf behavior, classifying its traffic patterns and proposing a
behavioral-based solution that is capable of detecting and preventing the
Ultrasurf traffic at the network level.
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