Layer 2 Tunneling Protocol


Layer 2 Tunneling Protocol (L2TP) is a protocol used to support virtual private networks (VPNs) or as part of the delivery of services by internet service providers. It creates a tunnel between two L2TP connection points and allows the transmission of data with necessary authentication and encryption. It is essentially a means of transporting data between remote users and private corporate networks.


The phonetics of the keyword “Layer 2 Tunneling Protocol” is “ˈlei.ər tu: ˈtʌn.əl.ɪŋ prəˈtoʊ.kəl”.

Key Takeaways

  1. Layer 2 Tunneling Protocol (L2TP) is a protocol used by Internet Service Providers to enable the operation of a Virtual Private Network (VPN). It essentially acts as a ‘tunnel’ that can carry other traffic between two endpoints in a VPN network, offering a secure way to transport data.
  2. Unlike some other types of protocols used in VPNs, L2TP does not provide encryption or privacy itself. It is commonly paired with IPsec (Internet Protocol Security), which handles encryption of the data being transported. This pairing allows the data to be both tunneled and encrypted.
  3. L2TP is a standard protocol and is supported by most devices. It combines the best features of two other tunneling protocols, the Point to Point Tunneling Protocol (PPTP) and Layer 2 Forwarding Protocol (L2F), offering efficient and flexible functionalities.


Layer 2 Tunneling Protocol (L2TP) is an important technology term because it refers to a protocol that allows the creation of virtual private networks (VPN). This is significant as VPNs are essential in present day computing for providing secure connections over the internet, particularly for businesses transmitting sensitive data. L2TP is used to support VPNs because it can facilitate the tunneling of data between two points over an agreed upon network. This tunneling obscures the data from potential interference or spying, bolstering data security. Moreover, it also supports multi-protocol, meaning it can carry numerous types of traffic such as IP, IPX, or NetBIOS. Therefore, the functionality and versatile nature of L2TP makes it an important part of secure, remote computer networking.


Layer 2 Tunneling Protocol (L2TP) serves a core purpose in providing security in the communication process, especially in instances where data needs to be transferred over public networks such as the internet. In simple terms, it’s like a ‘tunnel’ established between two points to facilitate secure data transfer. Often used in Virtual Private Networks (VPNs), L2TP allows the creation of a secure and private connection, often referred to as a “tunnel”, between the user’s device and a remote server through the internet which is inherently unsecured. By coupling it with encryption protocols, any data in transit is safe from eavesdropping ensuring data privacy and security.In a more specific application, mobile service providers take advantage of the L2TP for the deployment their Virtual Private Network (VPN) services. This technology gives them the ability to offer their users secure access to a business network from multiple remote locations. Hence, users can take advantage of tunnelling to connect their mobile devices to their work-based VPNs securely, and access their work network as though they are connected locally. Therefore, L2TP plays a significant role in enabling remote work capabilities and fostering efficient business operations without compromising the security of sensitive company data.


1. Virtual Private Networks (VPNs): Many companies use VPNs to provide a secure connection for remote workers. VPNs often use Layer 2 Tunneling Protocol (L2TP) due to its ability to encrypt data as it travels from one point to another, protecting the confidentiality and integrity of the information. 2. Internet Service Providers (ISPs): ISPs often use L2TP to manage their networks, particularly when it comes to broadband and DSL services. L2TP allows ISPs to separate data into individual tunnels for each customer, enabling better management of bandwidth and improving network efficiency.3. Telecommunications: Telecom companies use L2TP for “multiprotocol” and “bisynchronous dial” services, which require multiple data channels. For instance, L2TP allows cell phone service providers to handle voice and data transmissions simultaneously. The Tunneling protocol separates each type of data and sends them over different channels, improving the overall quality and reliability of the service.

Frequently Asked Questions(FAQ)

Q: What is Layer 2 Tunneling Protocol (L2TP)?A: Layer 2 Tunneling Protocol is a system protocol which enables the creation of Virtual Private Networks (VPNs). It’s basically a protocol that supports the tunneling of data between two points on a network.Q: How does L2TP work?A: L2TP works by sending data through what is known as a “tunnel” between two points on a network. This tunnel is created by encapsulating the data packet in an additional header that has routing information to allow it to traverse the network.Q: What is the relationship between L2TP and IPSec?A: They often work together to provide a higher level of security. While L2TP creates a virtual private network, it does not encrypt the data. IPSec usually comes in to encrypt the data and keep it secure as it travels over the internet.Q: Does L2TP provide encryption?A: No, L2TP itself does not provide encryption. It purely handles the tunneling of data. However, it can be combined with another protocol like IPSec to get encryption.Q: Why is L2TP used with VPN?A: L2TP is utilized with VPN to enable remote users and offices to access the internet securely. It creates a private, encrypted tunnel for transmitting data, protecting the data from potential threats.Q: What are the benefits of L2TP?A: L2TP supports multi-protocol, meaning it can encapsulate all kinds of protocol data packets, providing flexibility. It is also frequently paired with another protocol to provide encryption, offering enhanced security for VPN connections. Q: Is L2TP safer than PPTP?A: Yes, generally L2TP is considered safer than PPTP because it can be paired with IPSec for encryption, and its double encapsulation makes it harder to crack. However, this additional security can make it slower than PPTP. Q: What ports does L2TP use?A: L2TP uses UDP ports 500 and 4500 for the IPSec control path and port 1701 for the L2TP traffic.

Related Tech Terms

  • Virtual Private Network (VPN)
  • Data Encapsulation
  • Tunneling
  • Point-to-Point Protocol (PPP)
  • Internet Protocol Security (IPSec)

Sources for More Information


About The Authors

The DevX Technology Glossary is reviewed by technology experts and writers from our community. Terms and definitions continue to go under updates to stay relevant and up-to-date. These experts help us maintain the almost 10,000+ technology terms on DevX. Our reviewers have a strong technical background in software development, engineering, and startup businesses. They are experts with real-world experience working in the tech industry and academia.

See our full expert review panel.

These experts include:


About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

More Technology Terms

Technology Glossary

Table of Contents