Outline VPN is a free and open-source tool that deploys Shadowsocks servers on multiple cloud service providers.

Outline was developed by Jigsaw, a technology incubator created by Google.

The two technologies are similar in the way they can be used to redirect network traffic and make it appear as originating from another device (the server), and hide the traffic's final destination from observers and filters until it reaches the proxy server.

Outline is not an anonymity tool, and it does not provide the same degree of anonymity protections as Tor Browser, which routes traffic through three hops rather than just one and also protects against attacks like browser fingerprinting.

However, Eddy criticized the software for not encrypting all traffic on Windows, and warned users that "individual use may lack some anonymity compared [to] large VPN companies".