Which is better IPsec, PPTP or OpenVPN?
Presently proXPN support all three of the above protocols. you can in most cases either manually configure the connection to the respective protocol or use our native clients.
NOTE: Apple has discontinued support of PPTP in the latest version of their OS.
IPsec is a relatively new protocol that provide stronger and more stable encryption. IPsec offers improved ability to reconnect when an internet connection is interrupted. IPsec offers great stability especially when you move often between wifi and mobile data usage as the protocol allows for "on demand" thus providing greater service reliability.
Typically, OpenVPN will work in places where PPTP VPN accounts are blocked. This is because OpenVPN runs over SSL, which is the same technology that web browsers use to secure connections at sites like banking, etc. So OpenVPN traffic looks just like an encrypted web browsing session. OpenVPN does have a couple of downsides, though - lack of portability is probably the biggest. For almost all users, OpenVPN requires third-party software to run on every OS - so you have to download and install extra software to manage your OpenVPN connections.
PPTP VPN's main advantage is portability. It's built into almost every OS, including IOS (iPad/iPhone), Windows Mobile, and even Windows and Mac OS X - and even Linux has support for PPTP VPN. But it does have some downsides - it's easy to block and many people believe that it is not as secure as other VPN protocols.
We have seen PPTP VPN services blocked in places like China and also in parts of the Mid-East (Like Oman, or Iran, for example) - but this is not always the case. Some of our users report no problems with PPTP VPN. But you can bet that if you're having connection errors (other than user/pass failure) that PPTP VPN is being blocked. If you are not sure you can always try PPTP first - if that fails, try OpenVPN (regular VPN). Misconfigured routers and routers that have ports blocked in any location can also cause problems with PPTP VPN.
In summary OpenVPN or IPsec should be your first choice. Both are solid and recommended to keep your communication secure.
To learn more on the respective protocols please see the below WIKIPEDIA articles: