VPN blocking is a technique used to block the encrypted protocol tunneling communications methods used by virtual private network (VPN) systems. Often used by large organizations such as national governments or corporations, it can act as a tool for computer security or Internet censorship by preventing the use of VPNs to bypass network firewall systems.
Video VPN blocking
Description
Blocking VPN access can be done a few different ways. Ports that are used by common VPN tunneling protocols, such as PPTP or L2TP, to establish their connections and transfer data can be closed by system administrators to prevent their use on certain networks. Similarly, a website can prohibit access to its content by blocking access from IP addresses that are known to belong to popular VPN providers. Some governments have been known to block all access to overseas IP addresses, since VPN use often entails connecting to remote hosts that do not operate under that government's jurisdiction.
As organizations have ramped up efforts to block VPN access bypassing their firewalls, VPN providers have responded by utilizing more sophisticated techniques to make their connections less conspicuous, creating a networking arms race. For instance, as the Chinese government began using deep packet inspection to identify VPN protocols, Golden Frog began scrambling OpenVPN packet metadata for its popular VyprVPN service in an attempt to avoid detection.
Maps VPN blocking
Government use
China
Chinese internet users started reporting unstable connections in May 2011 while using VPNs to connect to overseas websites and services such as the Apple App Store. Universities and businesses began issuing notices to stop using tools to circumvent the firewall.
In late 2012, companies providing VPN services claimed the Great Firewall of China became able to "learn, discover and block" the encrypted communications methods used by a number of different VPN systems.
Deng Jiewei, a 26-year-old from Dongguan in Guangdong province, has been sentenced to nine months in jail for selling VPN via his own website in March 2017.
In 2017, telecommunications carriers in China were instructed by the government to block individuals' use of VPNs by February 2018.
Iran
The government of Iran began blocking access to non-government sanctioned VPNs in March 2013, a few months prior to the 2013 elections, to "prosecute users who are violating state laws" and "take offenders to national courts under supervision of judiciary service". Use of VPNs approved by the government reportedly led to surveillance and inspection of private data.
Russia
In July 2017, the State Duma passed a bill requiring the Internet providers to block websites that offer VPNs, in order to prevent the spreading of "extremist materials" on the Internet.. Russian internet users have also reported a block on the ExpressVPN VPN service. In November, 2017 BBC made it clear that Russia has not banned VPN usage entirely. VPN usage is only banned when attempting to access sites already blocked by Roskomnadzor or Russia's governing body for telecommunications and mass media communications. Using a VPN for business or personal reasons to access legal sites in Russia is permitted.
Syria
The government of Syria activated Deep Packet inspection after the uprising in 2011 in order to block VPN connections. The censorship targeted different VPN protocols like OpenVPN, L2TP and PPTP.
VPN blocking by online services
Hulu
In an attempt to stop unauthorized access from users outside the US, Hulu began blocking users accessing the site from IP addresses linked to VPN services in April 2014. In doing so, however, the company also restricted access from legitimate U.S.-based users using VPNs for security reasons. VPN providers such as VikingVPN, NordVPN, Purevpn and TorGuard stated that they would seek ways to address this issue for their customers by speaking directly to Hulu about a resolution and rolling out more dedicated IP addresses, respectively.
Netflix
Netflix came under pressure from major film studios in September 2014 to block VPN access, as up to 200,000 Australian subscribers were using Netflix despite it not being available yet in Australia. VPN access for Netflix has, like other streaming services, allowed users to view content more securely or while out of the country. Netflix users have also used VPNs as a means of bypassing throttling efforts made by service providers such as Verizon. As of November, 2017 the Netflix VPN and proxy ban is still active. The CEO of Netflix, Reed Hastings made a comment in 2016 about the VPN market as a whole; "It's a very small but quite vocal minority."
See also
- Deep packet inspection
- Steganographic tunnel
References
Source of the article : Wikipedia