L2TP VPN in 2023: Advantages and Use Cases of Layer 2 Tunneling Protocol

VPN as a concept refers to a Virtual Private Network that is established between your device and a host. However, there are various protocols that allow us to establish a VPN connection. One of them that will be the protagonist of today’s article is L2TP (Layer 2 Tunneling Protocol). Let’s explore its pros and cons and see why you would eventually like to use this particular solution.

L2TP VPN in 2023: Exploring Advantages and Use Cases of Layer 2 Tunneling Protocol

L2TP as a Reliable VPN Solution

L2TP is one of the most widely used VPN protocols, being considered fast and reliable, as well as easy to set up. L2TP doesn’t provide native security and encryption features and for this reason, it’s often used paired with some other protocols, like IPsec  (Internet Protocol Security). Some important facts you need to know about L2TP

• Its principle of operation is to create tunnels between two endpoints, so you can transmit data over an insecure network securely.
• As mentioned, it can be used together with security and encryption protocols like IPsec, as it doesn’t offer native security and encryption features.
• L2TP can be used with a variety of platforms and devices, which makes it pretty versatile.
• It’s also widely used in the case of remote access VPN – when employees need to connect to the corporate VPN.

Unveiling L2TP Protocols and Components

L2TP’s operation is made possible due to an ensemble of various protocols and components, that work together to establish and maintain a VPN. They include:

• L2TP Data Connection is the component responsible for transmitting data that can be additionally secured with IPsec.
• L2TP Control Connection is responsible for setting up and maintaining the control aspects of the VPN tunnel and is often combined with L2TP data connection. 
• L2TP Access Concentrator (LAC) is the component, a network device or a server, that accepts incoming VPN connections. It also initiates and manages the L2TP tunnels with remote clients.
• L2TP Network Server (LNS) is responsible for terminating incoming L2TP connections and forwarding user data to the appropriate destination on the network. 

Understanding L2TP Access Concentrator

Let’s now have a bit closer look, particularly at  L2TP Access Concentrator. This component is responsible for accepting the incoming data and directing it to the LNS, negotiating through P2P connections. Here are its main tasks:

• Accepting Incoming Connections: LAC is responsible for establishing the necessary tunnels and sessions when a remote client initiates an incoming L2TP connection.
• Authentication and Authorization: LAC performs authentication and authorization of users accessing the network.
• Data Routing: Through the previously established tunnel, LAC routes data between the remote client and the appropriate network resources.

Diverse Applications of L2TP

Besides VPN, L2TP is in fact a variety of possible applications. It started as a replacement of dial-up connections for remote networks to make corporate networking faster and cheaper, with options to increase the general level of security. Nowadays there are the following common uses of L2TP.

Extending LANs with L2TP Technology

When used with Control Connection Endpoints (LCCEs), L2TPL allows enterprises to add remote devices to their LAN networks, eventually expanding them, which is especially useful for establishing a remote working process. This allows to expand the corporate networking in a simple and efficient way and options to increase security.

L2TP's Role in ISP Networks

ISPs implement L2TP to partition their capacities and sell them to private clients. L2TP allows, in particular, isolating and routing of some parts to the clients by means of LAC while securing it through IPsec.

L2TP Enhancements for Public Wi-Fi Networks

L2TP is used to set up public Wi-Fi networks. Instead of setting up each single access point independently, what L2TP allows is to set up a network of points interconnected through L2TP, which makes the Wi-Fi network configuration cheaper and more convenient. This makes especially sense for extensive organizations, such as airports or colleges that need Wi-Fi access points at different locations. 

Pros and Cons of L2TP

L2TP is one of the VPN protocols available, a pretty popular one having it’s strong sides, but also certain flaws. Let’s see:

Pros of L2TP

Compatibility: L2TP can be implemented almost on any of the widely used platforms, which makes it a pretty versatile solution.

Reliability: L2TP is considered reliable since it can maintain connections even if the network conditions aren’t the best.

Ease of Setup: In comparison with other VPN protocols, L2TP is relatively easy to install.

Ideal for Remote Access: Besides being a good option for personal VPNs, L2TP is suitable for creating corporate VPNs that let employees remotely access the corporate network.

Security with IPsec: L2TP is highly suitable to be combined with IPsec, which in turn provides data encryption and authentification, excluding the possibility of the user’s data being compromised on its way.

Limitations of L2TP Technology

The need for IPsec: Since L2TP doesn’t provide security measures natively, the installation of IPsec or similar solutions is necessary in situations where security matters. Although it is generally not regarded as a problem, this requires additional actions from the side of the user.

Potential for NAT Traversal Issues: L2TP may face certain problems when dealing with Network Address translation devices. In this case, you might need to apply special techniques known as NAT-T (NAT Traversal) to mitigate these issues and continue working with L2TP.

Limited Anonymity: L2TP may be not exactly the optimal solution for users seeking maximum anonymity since it doesn’t hide the source IP.

Performance Overhead: When used together with IPsec, additional resources may be involved in encryption and decryption processes, reducing the performance compared to one without L2TP.

Firewall Compatibility: Some firewalls may occasionally block the L2TP traffic, especially in case non-standard ports are used, which can be a reason behind various connectivity issues.

FAQ

Why do I need to use a VPN?

Using a VPN will allow you to browse the internet anonymously and without the risk of your data being compromised. A VPN hides your actual location and IP while your data is encrypted. This can be especially vital whenever you use public Wi-Fi where you aren’t sure about its source. Besides that, a VPN also hides your data from the internet service provider and third parties that might be interested in getting access to it.

Besides the above, VPNs are widely used to access resources with access restricted to certain locations, which opens a lot of useful tools and content.

Can VPN be Used on Mobile Devices?

VPN can be used on mobile devices just like on PCs. You’ll just need to install the corresponding applications and apply the settings depending on your provider and their approach.

How Long Can We Expect It to Persist?

It’s not clear how long the VPN technology will remain relevant, but such things as privacy and security will hardly lose their importance. As long as there is no better way of maintaining security and privacy while browsing, a VPN will persist.

What Sets Different VPN Protocols Apart?

Different protocols are based on different approaches and components, each having its pros, cons, and particular usage cases. If you want to get the most out of your VPN and choose the options that are ideal for your particular usage case, you should study the specificity of each protocol. The article above is intended for you to understand the specificity of the L2TP VPN protocol. Research other VPN protocols to understand, which one is optimal for your particular case.

How does double encryption work?

Double encryption is a kind of encryption that suggests that the internet traffic is routed through two or more VPN servers, which makes your encryption more complex and hence more secure. During the double encryption, your data is initially encrypted at the first server of the network. Then it’s sent to an intermediary server that decrypts it and encrypts it again, sending it to the third server that decrypts it and sends it to its destination.