PPTP (Point-to-Point Tunneling Protocol) was created for dial-up networks and specification for PPTP was published in July 1999. PPTP uses a control channel over GRE and TCP tunnel operating to encapsulate PPP packets. PPTP was developed by Microsoft, US Robotics and several vendor companies and it has long been protocol standard worldwide.
PPTP protocol has been analysed by security analysts and they found serious security vulnerabilities in this protocol.
PPTP protocol is often not enough to provide the level of privacy that most users are looking for these days. All in all PPTP is simply outdated and uses very weak encryption.
Even though it is outdated and contains security vulnerabilities, this protocol is still very popular because PPTP is simple and easy to set. PPTP is the fastest protocol and does not compromise your Internet speed.
I don't recommend that you use PPTP for secure and private communication. This protocol is no longer secure.
Secure Socket Tunneling Protocol or (SSTP) is a type of VPN tunnel that provides you technique to transport PPP traffic through SSL/TLS channel. It is developed by Microsoft Corporation.
It uses 2048 bit encryption and authentication certificates. It has same advantages over OpenVPN because it can bypass some firewalls and can operate on network that blocks VPN protocols.
It uses AES in its encryption and this protocol is available for Linux and Microsoft users. I have no information yet that SSTP will be offered to Apple users. Security level of this protocol is high.
Layer 2 Tunneling Protocol or L2TP is a tunneling protocol used to support VPN or as part of ISP's delivery services. L2TP prevents data from being changed while transferring between the receiver and sender. Actually, L2TP can't encrypt your data on its own. It encrypts your data via IPSec protocol
L2TP protocol is supported by Windows, Linux and MAC OS.
L2TP is less efficient than SSTP and OpenVPN protocols because it encapsulates data twice. Because of that, it uses double encapsulation and this is a reason why this protocol is slower protocol than SSTP and OpenVPN protocols.
OpenVPN is open source software that implements VPN (virtual private network) methods for creating secure site-to-site or point-to-point connections. OpenVPN allows peers to authenticate each other using a pre-shared certificates, secret key or username/password. This application was created by James Yonan and it is published under the GNU General Public License.
When we talk about those main protocols, OpenVPN protocol is considered as the most secure and reliable. Precisely, it uses OpenSSL and SSLv3/TLSv1 library protocols. OpenVPN can be set up to run on TCP port 442 or UDP port.
When we compare previous discussed protocols with OpenVPN, OpenVPN isn't already built in operating systems. It is easily set up through third-party software.
When you are looking for reliable VPN company, I strongly suggested you to find one which offers OpenVPN protocol. This protocol is considered to be the most secure and reliable. Please visit vpn24x7 and read our VPN recommendation.