What is the Layer 2 Tunneling Protocol (L2TP)?

fact, The prowess that L2TP can leverage for connectivityInis of interest to VPNs, while ISPs can foster VPN operations with it. The Layer Two Tunneling Protocol (L2TP) is a protocol used by both Internet Service Providers (ISPs) and Virtual Private Networks (VPNs).

L2TP is the outcome of combining two older protocols: Microsoft’s Point-to-Point Tunneling (PPTP) and Cisco’s Layer 2 Forwarding (L2F). The hybrid outcome, both, combines the most effective of L2TP worlds and improves upon them significantly. In fact, The protocol was born as the last century ended to replace earlier protocols. Technically, it’s the standard RF C26661.

HereL2TPs what you need to know about ’:

• It needs to be paired with another protocol to maximize its benefits.
• It’s usually paired with IPSec, which brings security to the data load.
• The combination of L2TP and IPSec opens up a broad spectrum of possibilities regarding security features because it enables the use of AES 256-bit and the 3DES algorithm.
• L2TP’s packets feature double encapsulation, which improves their security. However, it also makes the protocol more taxing on the equipment.
• L2TP’s port of choice is 1701. But once IPSec comes into the mix, various other ports can come alive. For instance, port 500 will manage the Internet Key Exchange (IKE), 4500 for NAT, and 1701 (the original one) for L2TP traffic.

Howdoes L2TP work?

L2TP creates a tunnel between two endpoints on the the from another perspective : cyberspace L2TP Access concentratorLAC () and the L2TP network server (LNS).

Once the connection between the two becomes active, the protocol enables an encapsulated PPP layer.

Then, the next step is initializing the PPP connection from the ISP to the LAC. When the LAC accepts it, the PPP hyperlink comes online.

Indeed, Next, a novel complimentary slot becomes assigned inside the tunnel, and the request goes to the LNS.

At this point, the connection needs authentication. theOnceauthenticity is established, a virtual PPP interface comes alive more than ever . And immediately, all the connection frames can travel around the tunnel freely.

Interestingly, The last step completes at the LNS endpoint, where the protocol processes the accepted frames and removes the L2TP encapsulation.

How areandIPSec as it turns out L2TP protocols related?

Perhaps, you may frequently encounter the term “L2TP/IPSec” among connection protocols when looking for L2TP in a VPN. Maybe you often discover “IPSec” whenever you read about the L2TP protocol.

IPSec (thefor from another perspective acronym “Internet Protocol Security”) is a separate connection protocol frequently used with L2TP.

As the as it turns out name suggests, IPSec ensures “security” to the “internet protocol” by encrypting the data packets exchanged between two computers in a networkIndeed, . Hence, usingIPSec in tandem with L2TP improves a connection’s security.

L2TP doesn’t perform the its top when at network deploys it alone. Interestingly, However, it becomes more robust, reliable, and efficient when running with IPSec. That’s why most VPN providers deploy the two protocols together to provide improved security to the users.

The L2TPunder as it turns out IPSec pairing – Looking / the hood

Interestingly, Since IPSec is a protocol that brings out the most effective in L2TP, it’s good to understand these twohowprotocols interact and potentiate each other. So :’s how it goeshere

1. The negotiation for the IPSec security association (SA) occurs. (Here, “security association” is the agreement of shared security attributes between two networks to ensure secure data exchange.) This IPSec SA negotiation typically happens via IKE over port 500.
2. The protocol establishes the “Encapsulating Security Payload” (ESP) process as the transport mode. This ESP operates on top of IP (with IP protocol number 50), establishing a secure channel between two entities (such as the client and the VPN server) in a network. However, until this point, no tunneling happens.
3. The IPSec protocol has completed its job at this point, so this is where L2TP comes alive. It’s in charge of creating the tunnel between both endpoints. L2TP sets the tunnel up via TCP port 1701. The negotiation for the tunnel occurs over IPSec encryption.

L2TP protocol as it turns out connectionspeeds

Every internet end-user likes to have the best possible connection speeds, even when prioritizing security. So, you might wonder how quick L2TP is.

In essence, the L2TP protocol can be exceedingly fast when used alone, as it only creates a tunnel for information exchange, employing no encryption.

Indeed, But we can’t apply it singly for the same reason. Otherwise, doing so would render the connection vulnerable to interception by third parties and snoopers.

That is why the service providers often pair it with IPSec to introduce encryptionIndeed, . Indeed, However, the speeds will suffer since you are almost always using two protocols in tandem. it won’tButbe a noticeable impact if you have a good base rate.

Interestingly, For instance, if you get 100mbps notice more from your ISP and have an impressive CPU, you won’t or any of the work both protocols are doing.

L2TP in modern times and pros Protocol cons

Immediately that you know how swift L2TP is while ensuring almost no security on its own, you might wonder if it is worth adopting at all.

To response this concern, let’s at both sides oflookthe coin.

L2TP advantages

• Provides excellent security when paired with IPSec.
• Compatible with most devices and operating systems. (You will find it available as the built-in protocol in Windows and macOS.)
• Easy to configure.
• Supports multithreading for improved performance.
• The double encapsulation feature ensures improved data verification.

Disadvantages of L2TP

• As an individual protocol, it’s fragile in terms of security.
• According to Edward Snowden, the NSA knows how to crack this protocol successfully. (Of course, we will never be able to prove Snowden’s assertion. But we do know that the protocol is weak.)
• Double encapsulation in L2TP requires more resources, which can be slightly slower than the alternatives.
• It may often encounter hindrances by NAT firewalls unless it is set up to bypass the filters.

L2TP VPN key features

An L2TP VPN has some unique features to offer you. Here theyare :

• Secure connection. You can deploy AES-based or 3DES-based encryption within the L2TP tunnel. AES is the military-grade encryption algorithm that’s the standard among VPNs and intelligence agencies globally.
• Improved link stability. Once you link to your VPN’s server, you want things to keep running smoothly. L2TP makes for more stable links because the configuration goes through the UDP port 1701, port 500 for key exchange, and 4500 for NAT.

Is this getting too geeky for your taste? Don’t worry; you don’t need to understand all the technical details to enjoy the advantages of this protocol.

Interestingly, The thing to remember is: if your VPN offers you this option, take it. It’s excellent for security without losing too much speed.