PPTP vs. L2TP: Top 5 Differences To Know

Understanding Point-To-Point Tunneling Protocol (PPTP)

PPTP, or Point-To-Point Tunneling Protocol, is probably the oldest VPN protocol that is still active. It is compatible with all the versions of OSs and has been available since Windows 95. This stable protocol functions on TCP port 1723 and continues to be popular.

The major benefit of the protocol is in its availability. As for the minuses, we can specify some security vulnerabilities. Lots of cybersecurity experts specify the issues with the authentication protocols that directly impact security.

These factors make PPTP an ideal choice for clients who prioritize speed characteristics, and security is not their major concern. Among the most standard user cases, we can specify usage on devices with constrained processes and for audio/video streaming.

However, these were not the only user cases for PPTP. Despite some security issues, large companies prefer this protocol for VPN deployment. This relates to the telecom companies and public ISPs. Huge businesses make this choice because of economic reasons.

The construction of VPN across TCP/IP network, this protocol guarantees secure information transfer for the remote clients without the necessity in the private network.   

Exploring Layer Two Tunneling Protocol (L2TP)

L2TP, or Layer Two Tunneling Protocol, is a kind of mixture of Layer 2 Forwarding and PPTP. This protocol is predominantly used for the enabling of VPN services by ISPs.

To guarantee an efficient level of security between the networks, L2TP consists of 2 major components. The first one is the network server that is needed for the authentication of PPP streams and termination of calls, and an access concentrator that is necessary for the physical termination of calls.

To create the highest possible level of privacy and security, a specific encryption protocol is used. With this protocol, most types of data transfer over IP or L3 network. That means a tunnel is deployed that connects LNS and LAC.

L2TP is a beneficial option for users who plan to minimize dial-up costs while connecting to the enterprise network remotely and, at the same time, increase the speed of connectivity. The usage of L2TP with PPP that are configurated at user sites and ISP side can significantly influence the connectivity speed.   

PPTP vs. L2TP: Key Distinctions

Let’s discuss some of the major distinctions between L2TP and PPTP.

1. Historical Background

The creation of PPTP started in the 1990s when huge companies such as Nokia and Microsoft united. The engineers had the task of creating an encryption tool for Windows so the users could try new opportunities such as e-commerce.

Once PPTP was created, it functioned by creating data packets that formed a tunnel. To legitimize the traffic, there was also an added authentication process. Data encryption was used for the packets. The only issues that were noticed related to the security considerations. The cyber-attacks changed, and their methods improved greatly. The official specification for PPTP appeared in 1999, and it includes all the tech details of the protocol.

Now, let’s proceed to L2TP, which was based on PTPP and used to support VPN connections. This approach is characterized as a series of communication protocols that are necessary for tunneling capabilities.

L2TP guarantees encryption for VPN and, in addition to this, Layer 3 protection and IPSec. The protocol was created by Cisco and Microsoft. The later version of this protocol was released in 2005 and is called L2TPv3.

2. Functionality and Mechanism

PPTP is compatible with most OSs, specifically Windows. It has great speed characteristics, but unfortunately, there are some issues with security that are related to the cryptography. Despite the drawbacks, lots of companies use this protocol for VPN apps.

As for the functioning of this protocol, it routs over TCP port 1723. The deployment of the tunnel is made via GRE and authentication with PPTP.

PPTP is extremely easy to set up on the VPN server. Practically, users of the most popular OSs can apply the protocol without the installation of additional software.

As for the mechanism of L2TP, it technically offers means for the VPN functioning. It gives everything except for the encryption methods. However, that is not an issue because additional security can be achieved with IPSec.

In L2TP, the support of the tunnel is made by PPP. Sure, it is possible to connect VPN server and user only with L2TP, but it will directly impact the security. There are 4 various tunneling models of this protocols such as compulsory for remote dial, compulsory for incoming calls, voluntary tunnel, and L2TP multi-hop.

Data in this protocol undergo encapsulation twice. The first is done with PPP and the second with IPSec. Also, information is encrypted prior to its transmission. The double encapsulation guarantees better protection and fewer security risks.  

3. Operational Differences

In PPTP, the following transport protocols are used: TCP and GRE. When compared with L2TP, it is considered to be less efficient due to the separation of data streams and control.

Also, in PPTP, the least secure authenticator is used. Sure, MS-CHAPv2 can be changed into the more secure option, however, the configuration process of another authenticator is challenging on PPTP.

The major benefits of PPTP are that it has lower costs, it's faster, and it is easier to use. PPTP doesn’t need PKI and uses 128-bit encryption.

L2TP uses such transport protocols as UDP or TCP. Because there is no division in control streams and data streams, this approach is more efficient.

L2TP is much more secure because of the usage of integrity checks, double encapsulation, and the necessity of authentication certificates. To add even more security, it is possible to use IPSec. Because of more computer resources usage, it might be slower.  

4. Security Aspects

PPTP is an extremely popular option because of its higher compatibility and simplicity of implementation, but there are definitely some issues with the security aspects. Such problems make it impossible to use PPTP for secure communication. The first issue that was noticed related to CHAP and then was MPPE encryption, which is also not the best one.

Hashing algorithms are also extremely risky ones, because attackers can become in a node and use really sensitive information. In addition, the incorrect configuration of PPTP can even create more security vulnerabilities. To minimize some risks, it is possible to use EAP-TLS instead of the existing variant, but this approach might not be the best one for all apps.

L2TP is considered to be more secure when compared with PPTP. However, it is important to clarify that L2TP doesn’t have any serious encryption; IPSec is used to solve this problem with security. The process of protection works the following way – first encapsulation is made according to the principle of PPTP, then the second one is based on IPSec.

When talking about reliability, this protocol is really safe in combination with IPSec. In case users want to have a more secure protocol, they can consider other options.

5. Advantages and Disadvantages

Advantages of PPTP:

• Speedy VPN protocol.
• Simplicity of the configuration.
• The connection can be established on various platforms.
• Lower transmission costs
• Easy in terms of administrative tasks.

Disadvantages of PPTP:

• Low-quality encryption process.
• Connections can be blocked by firewalls.
• The necessity of routers to be equipped with Passthrough.

Advantages of L2TP:

• A much stronger security characteristic when adding IPSec.
• The flexibility of level 2 networking.
• The protocol can use different tunnel media.
• The simplicity of the VM transfer.

Disadvantages of L2TP:

• Some issues with firewalls might occur.
• Slower speed because of the double encapsulation.
• Some instabilities might occur compared with other available protocols.

Final Thoughts

Now, you have a clear picture of the pluses and minuses between these 2 protocols so you can choose the most suitable one for your case. There are no good or bad choices of the protocol; there are only those that suit your application and those that don’t.

PPTP is way faster and easier but has some issues with security. At the same time, L2TP is way more reliable and stable, with stronger encryption. Before making the final choice, we highly recommend reviewing the major pluses and minuses one again.