oLink is a firewall circumvention open-source tool set. It enables content providers from a free country like the US to target their audience in China.
A content provider first mirrors its webpages on a platform such as GitHub.com that the adversary cannot afford to block. The content provider then creates unblockable URLs to be distributed via emails or social media platforms. Targeted users just need to click on a URL and view content from a standard browser with no need to install any software.
How oLink fits into the ecosystems of firewall circumvention:
- oLink does not use the cat-and-mouse model. A URL for a webpage is unblockable unless the adversary is willing to pay the price of blocking an entire site such as Github.com. However, even if GitHub were blocked in China, there will be replacement(s) and there will always be some platforms that the CCP cannot afford to block. Today we can use GitLab or BitBucket as alternative platforms to GitHub. As a result, an unblockable URL can be further shared with other users.
- Content providers can actively push their unblockable URLs to their targeted users. This is analogous to an advertiser creating ad campaigns to drive traffic to its website. This cannot be easily done with other circumvention tools.
- If the adversary pressures the hosting vendor such as GitHub to remove the hosted content, the vendor will have a very hard time to pinpoint the locations. It is because a mirrored webpage is randomly divided and the resulting pieces are hosted in many locations.