BeyondCorp is an implementation, by Google, of zero-trust computer security concepts creating a zero trust network. It was created in 2009 in response to Operation Aurora. An open source implementation inspired by Google's research paper on an access proxy is known as "transcend". 
Unlike traditional VPNs BeyondCorp's access policies are based on information about a device, its state, and its associated user. BeyondCorp considers both internal networks and external networks to be completely untrusted, and gates access to applications by dynamically asserting and enforcing levels, or “tiers,” of access.
- "BeyondCorp: A New Approach to Enterprise Security - USENIX". www.usenix.org.
- "BeyondCorp: Design to Deployment at Google - USENIX". www.usenix.org.
- Spear, Batz; Beyer, Betsy (Adrienne Elizabeth); Cittadini, Luca; Saltonstall, Max (2 September 2018). "Beyond Corp: The Access Proxy". Cite journal requires
- "Google BeyondCorp Breaks With Enterprise Security Tradition - InformationWeek".
- "The perimeterless, ever-shifting enterprise: What would a real, red-blooded IT team do?".
- "NIST Special Publication, Zero Trust Architecture (2nd Draft)".
- "BeyondCorp: The BeyondCorp Story". Retrieved 22 April 2020.
- transcend github, accessed: 2019-04-22.
- "Design to Deployment at Google" (PDF). Retrieved 23 April 2020.