The PPTP protocol was developed by a group of vendors during the late 1990s. It’s still very popular, although it contains many security issues. The part of its popularity lays in the simplicity of the implementation and the built-in support in virtually every operating system.
The specification for PPTP was published in RFC2637. This type of VPN is well known for implementing on the Microsoft Windows platforms. Additionally, many other vendors implemented (at the very least) the client version and the server part is implemented in Mikrotik RouterOS, too.
MiViLiSNet 