In telecommunication, it is rare that 25 years old protocols still exist in practical use. Today we will describe one of the oldest VPN protocols still in use. A point to point VPN is also known as a PPTP.

What is PPTP?

PPTP represents data-link layer protocol and networking standard for connecting to virtual private networks based on the Point-to-Point Protocol. PPTP is the standard protocol for wide area networks (WANs)  since Windows 95 and all Windows versions. This protocol allowing users to access a network from a remote location and can be routed over an unsecured public network such as the Internet.

Using PPTP, it is possible to create virtual private networks (VPNs) and tunnel TCP/IP traffic through the Internet.

Point-to-Point Tunneling Protocol (PPTP)

What is Point-to-Point Tunneling Protocol?

The Point-to-Point Tunneling Protocol is a network protocol used to implement Virtual Private Network (VPN) tunnels between public networks. PPTP servers are also known as Virtual Private Dialup Network (VPDN) servers.

Using this PPTP protocol, users can easily use LAN (local area network) to access the internet instead of using complicated connection protocols such as Public Switched Telephone Network (PSTN), dedicated leased-line connections, etc.

What is a PPTP port?

How PPTP works?
In the first step, PPTP sends packets into PPP frames and creates a “tunnel” across a LAN or WAN link. It uses Internet Protocol (IP), NetBEUI, or Internetwork Packet Exchange (IPX) packets during tunneling. The idea is that the PPTP tunnel creates authentication and data encryption and securely transmits data over networks.

PPTP tunneling can be:

• Compulsory tunneling: This tunneling is supported by routers or by network access servers (NAS’s). Windows 10 has Compulsory tunneling.
• Voluntary tunneling: Microsoft Windows 95, Windows 98, Windows NT, or Windows 2000 have voluntary tunneling, and this type does not use bridges and does not require support from an Internet service provider (ISP).

Now let us compare two famous protocols:
PPTP vs. L2TP
PPTP (Point-to-Point Tunneling Protocol) is lower level encryption method compared to L2TP and OpenVPN. L2TP (Layer Two Tunneling Protocol) is more secure than PPTP as it uses higher 256-bit encryption. However, PPTP is faster than L2TP because L2TP encapsulates data twice, making it less efficient and slightly slower.

PPTP vs. OpenVPN

PPTP  has a lower level encryption method compared to OpenVPN. However, with 128-bit keys, PPTP is slightly faster than OpenVPN and has an easy setup.OpenVPN provides the best performance (better than PPTP) in its default UDP mode.

RAS PPTP

A remote access service (RAS) is a combination of hardware and software connecting a client to a host computer. PPTP and RAS use authentication and encryption methods to create a virtual private network.PPTP Is designed to allow users to connect to a RAS server from any point on the Internet. The end-users dial into their ISPs and use PPTP to set up a “call” to the server over the Internet.

PPTP troubleshooting

If you have a  PPTP troubleshooting over a TCP/IP connection, use ping ( signal sent to a host that requests a response) to determine whether you are connected to your PPTP server.

PPTP Security

PPTP provides weak protection to the integrity of the data being tunneled because of the lower encryption level. The RC4 cipher does not verify the data’s integrity during encryption because it is not an Authenticated Encryption with Associated Data (AEAD) cipher.