A Digest on L2TP Protocol
The Layer 2 Tunneling Protocol (L2TP) is a standard protocol for tunneling L2 traffic over an IP network. Its ability to carry almost any L2 data format over IP or other L3 networks makes it particularly useful. But L2TP remains little-known outside of certain niches, perhaps because early versions of the specification were limited to carrying PPP — a limitation that is now removed.
Layer 2 Tunneling Protocol (L2TP) is an advanced networking protocol that is used to support VPN services. A common misconception is that L2TP is an encryption protocol. The truth is, L2TP is a tunneling protocol and doesn’t provide any form of encryption by itself. It has to be paired with an encryption protocol which it passes through the tunnel in order to successfully provide VPN users with privacy. L2TP protocol is considered to be one of the most secure protocols that are compatible with all operating systems and platforms. Not only is L2TP protocol used by VPNs, but it is also used by internet service providers (ISP) to deliver their services in certain cases, for example when the ADSL is being resold.
L2TP protocol is usually paired with IPSec (an encryption protocol) to be referred to as L2TP/IPSec to provide authentication and integrity to a VPN network through which data is completely encrypted when it’s trafficked through the VPN tunnel. Most VPN providers use 256 bit keys for encryption to deliver a safe and secure networking environment to their users.
Advantages and Disadvantages of L2TP Protocol
So what are the pros and cons of L2TP protocol and where does it stand when it comes to providing security and anonymity over the internet? In this section, we will reveal the main advantages and disadvantages of L2TP protocols and how effective it is in providing security and anonymity to users online.
L2TP Protocol PROS
• Compatibility: L2TP protocol is widely supported by all operating systems, like: Windows, Linux and MAC OS.
• Configuration: L2TP protocol is easy to setup than other protocols because most platform come with an integrated L2TP support, facilitating its configuration process.
• Stability: L2TP protocol is known for being reliable and stable. It might be a little dodgy though when it is used with devices that are connected to NAT routers.
• Security: L2TP protocol is extremely secure because it doesn’t have any major vulnerabilities. L2TP is excellent in terms of security when it is conjuncted with other sturdy encryption protocols and security algorithms such as AES to provide maximum security.
L2TP Protocol CONS
• Speed: L2TP protocol is generally slower than other protocols because it wraps data twice which results in a slowdown in the data transfer process. However, this can be easily overcome when L2TP is paired with OpenVPN protocol, making the speed different hardly detectable.
• Ports: L2TP protocol uses fixed ports. “For instance, the L2TP/IPSec combination uses UDP 500 for key exchange, UDP 1701 for configuration and UDP 4500 for traversal. Since it uses fixed ports and protocols, it is easier to block L2TP than OpenVPN.” That is why, L2TP is not ideal to be used in countries, like: China and Iran due to their highly sophisticated filtering systems which rely on DPI (Deep Packet Inspection) technique which can easily block the L2TP protocol.
L2TP is an excellent VPN protocol that delivers the goods. While it falls just short of OpenVPN, it is quick to setup, provides excellent security and supports a wide variety of devices which makes it an great choice for use in most environments.