WireGuard VPN: How does the Wireguard VPN protocol work?

What is WireGuard VPN?

Wireguard VPN, or Wireguard VPN protocol, is a set of rules that determine how data is encrypted and moved within a virtual private network (or VPN, for short). Its purpose is to ensure smooth, fast, and secure transmission of user data, when using a VPN.

WireGuard is popular for a few reasons. It works very quickly, provides a high level of security, and is written with relatively few lines of code. The lightweight nature of the protocol code is important because it makes deployment and debugging easier. 

The protocol also works on different platforms (such as Windows, Mac, Android), and is even integrated into the Linux kernel. Because of that, WireGuard has been used as the basis for many other advanced VPN protocols, including NordVPN’s own ultra-fast and secure NordLynx.

You can take a look at our video explaining what Wireguard is.

WireGuard's combination of speed and modern cryptography has made it an increasingly popular choice in the VPN market. Many different VPN providers adapted it soon after its release, while NordVPN took an additional step and used it as a basis for its NordLynx VPN protocol.

It’s safe to say, no one can deny the protocol’s importance. However, the question still remains: How does WireGuard work?

How does WireGuard work?

The WireGuard protocol works by setting up a connection between a client (your phone or computer, for example) and a VPN server. Like other encryption protocols, WireGuard communicates with the server and establishes an encrypted tunnel between the server and client by using WireGuard 51820 — a default (but configurable) WireGuard port. When data moves between these two nodes — the WireGuard client and the server — on the network, it is encrypted and scrambled into code that is indecipherable without the proper encryption keys.

So far, this is how every VPN protocol works. However, contrary to its counterparts, the WireGuard protocol differs in the speed with which it connects the client to the server and transfers data. Unlike other widely adopted protocols that use AES-256, WireGuard employs ChaCha20-authenticated encryption. ChaCha20 has a more efficient cipher design than AES-256, allowing faster encryption and decryption. 

Wireguard systems also rely on Curve 25519 — an elliptic curve (mathematical equation) that performs calculations to ensure strong security and fast cryptographic operations for encryption key exchange. 

Another key part of WireGuard’s safety is its reliance on cryptokey routing tables. These essentially are lookup tables that help systems determine which encryption keys and security associations to use when communicating with different network endpoints. Cryptokey routing tables allow tighter access control and map public keys to authorized IP addresses, significantly strengthening the protocol’s security model. Additionally, WireGuard rotates its session keys frequently to enhance protection during prolonged use, while maintaining its speedy connection.

Adding to its speed is the fact that the WireGuard protocol runs within the Linux kernel on WireGuard servers and Linux desktops. That is an additional benefit, mainly because other protocols have to switch between kernel storage and userspace for full functionality (slowing them down slightly), while WireGuard can run fully from the kernel. This and other aforementioned technical advancements give WireGuard at least several advantages over other protocols.

What are the key features that make WireGuard a secure VPN protocol?

The key features that make WireGuard a secure VPN protocol are:

• Modern cryptographic algorithms. Along with the Curve25519 and ChaCha20 algorithms, WireGuard employs Poly1305 for message authentication and BLAKE2s for hashing (a special math formula that scrambles information into a code that's always the same length — used to check if data has been changed or to create unique ID numbers). These modern algorithms are not only highly secure but also optimized for performance, beating older protocols (especially those that rely on AES) in encryption and decryption speed. The suite of WireGuard’s algorithms make the protocol more resistant to known vulnerabilities while meeting the current cybersecurity demands for both the latest tech and devices with limited resources (such as smartphones or single-board computers).
• Minimal codebase. With 4,000 lines of code, WireGuard has what is considered an extremely small and lean codebase. This minimalism makes the protocol easier to audit for vulnerabilities and reduces the potential for bugs, which are common in bloated or overly complex systems. Shorter code also means a smaller attack surface and fewer mistakes to exploit, making the protocol more secure against cyberattacks. Finally, the simplicity of the codebase ensures easier maintenance and faster fixes for any issues or vulnerabilities that may arise.
• Perfect forward secrecy (PFS). WireGuard supports perfect forward secrecy (PFS), a critical security feature that ensures encrypted sessions remain secure even if long-term private keys are compromised in the future. With PFS, encryption keys are generated dynamically for each session and are never reused. That makes it impossible for attackers to retroactively decrypt past communications, even if they intercept previous sessions. This feature is particularly important in preventing mass data collection attacks, where encrypted traffic is stored in the hopes of breaking its encryption later.

How does WireGuard enhance VPN security with modern cryptography?

WireGuard’s modern cryptography enhances VPN security by using a mix of top encryption algorithms. The ChaCha20 and Poly1305 algorithms are particularly important because they ensure quick encryption and authentication without requiring specialized hardware. 

ChaCha20 encrypts data by combining a secret key, a unique nonce (number used once), and a block counter to produce a pseudorandom keystream. And the reason why this algorithm is so fast is because it uses simple mathematical operations that are highly efficient on modern CPUs.

Poly1305, on the other hand, guarantees data hasn’t been tampered with. It calculates a unique "tag" for each message by using a key and the encrypted data. This tag travels with the encrypted message and is verified during decryption. If even a single bit of the message is altered, the authentication fails.

These algorithms work in tandem with a feature called perfect forward secrecy (PFS). PFS ensures that even if a hacker gets access to one encryption key, they cannot decrypt any past or future data. To do that, the feature exchanges temporary keys for each communication session without ever transmitting it over the network. Once the session ends, the keys are discarded permanently. 

In addition, Wireguard uses PFS frequently to rotate encryption keys, even during active sessions. That means if an attacker were to steal a session’s encryption key, they would only gain access to data for a short period, while older data (from previous sessions) and future data (in new sessions) would remain secure.

Finally, WireGuard uses cryptokey routing, a system where each user's cryptographic public key directly determines what network resources they can access. That eliminates the need for usernames and passwords, further enhancing the safety of this VPN protocol.

How does WireGuard cryptography compare to traditional VPN protocols?

WireGuard differs from traditional VPN protocols significantly. While protocols like OpenVPN and IPSec offer extensive configuration options and support multiple cryptographic algorithms, WireGuard intentionally limits choices to a single, modern cryptographic suite. That makes it faster, easier to implement, and widely accessible. 

Furthermore, WireGuard employs a simplified cryptographic approach compared to traditional VPN protocols like OpenVPN and IPsec and eliminates the complexity by reducing its codebase. This not only minimizes WireGuard’s attack surface but also makes security audits far more manageable.

Additionally, WireGuard's ChaCha20-Poly1305 tandem particularly excels on devices without hardware AES acceleration, delivering significantly faster performance than OpenVPN on smartphones, IoT devices, and older computers. Traditional protocols often rely heavily on AES encryption, which performs poorly without dedicated hardware support. Meanwhile ChaCha20 uses simple CPU operations that run efficiently on any processor. 

Finally, WireGuard's design and lack of complex handshakes (communication parameter establishments) result in near-instantaneous connections and minimal battery drain on mobile devices, addressing key weaknesses of legacy VPN protocols.

What are the advantages of WireGuard VPN?

The key advantages of WireGuard VPN include:

• Speed. The biggest benefit of using WireGuard is the speed it provides. VPNs inevitably slow down your connection because an extra step is being inserted into the data’s journey between the client device and the internet. With WireGuard, however, that reduction in speed is so minor that it’s barely noticeable.

• Minimal codebase. WireGuard consists of fewer lines of code than many other VPN protocols, making it easier to deploy and to troubleshoot. Wireguard VPN providers can find and resolve bugs quickly, because there is just less code to sort through when trying to identify problems.

• High security. While other protocols might be able to improve speeds by compromising on security, WireGuard provides very strong encryption. This combination of speed and security makes it one of the best VPN protocols available.

• Rapid reconnection. WireGuard can establish a new connection in milliseconds, allowing you to switch between networks and routers without waiting for your VPN to slowly reconnect. With other protocols, a network switch could result in a slow VPN reconnection.

• Open source software. WireGuard is open source, meaning that anyone can audit and edit its code. Consequently, tech experts and VPN providers alike can examine the code, find and fix problems, and even build on it to improve performance.

• Battery efficiency. WireGuard’s design reduces background processing and doesn't transmit data when idle. That saves resources and battery power, particularly on mobile devices.

• Cross platform compatibility. The protocol’s open-source design allows WireGuard to be available on every major OS (both mobile and desktop). It’s even accessible through Linux due to the integration with Linux kernel.

How does WireGuard address future security threats?

WireGuard protects against future security threats mainly by using PFS. However, it’s not the only line of defense. Wireguard’s small codebase makes it much easier for security experts to quickly spot and fix any vulnerabilities before hackers can exploit them. The protocol only uses the most modern, rigorously tested encryption methods that are specifically chosen to remain secure even as computers get more powerful over time. 

However, even with all these benefits, WireGuard is not quantum resistant, which may prove troublesome in the future. While currently in a prototype phase, quantum computers will be able to decrypt current encryption keys with ease, including those used in protocols such as WireGuard. It’s worth mentioning, though, that services like NordVPN are already using post-quantum encryption for some of their protocols (including WireGuard) to safeguard against this future threat.

Is the WireGuard VPN protocol secure?

Yes, WireGuard is a very secure protocol, mainly, because of the modern cryptographic techniques it uses. For example, WireGuard employs more efficient cryptographic keys compared to some previous protocols, managing to provide strong encryption because of the advanced algorithms it uses.

These algorithms include ChaCha20 for symmetric encryption, Poly1305 for authenticated encryption, Curve25519 for key exchange, BLAKE2s for hashing, and SipHash24 for hashtable keys. Their strong security properties and resistance to known attacks make WireGuard superior to protocols with older cryptographic methods that may have vulnerabilities.

While the algorithms are a huge part of WireGuard’s security appeal, the protocol's streamlined code is also among one of its greatest security advantages. Its short and simple code drastically reduces the likelihood of bugs and hidden vulnerabilities that often plague more complex VPN solutions. The clean, readable code has been tested through and through and has even led to its inclusion in the Linux kernel — a feat that requires meeting stringent security standards.

Downloading WireGuard (from official sources) gets users a protocol that has been designed with security as the primary focus. The combination of modern cryptography and minimal, auditable code makes WireGuard exceptionally secure for protecting your online privacy and data.

Are there any disadvantages of WireGuard VPN?

WireGuard does have a few disadvantages, though these are largely outweighed by its many benefits.

• Lack of obfuscation. WireGuard does not provide obfuscation, meaning that internet service providers (ISPs) can see when you are using it — although, of course, they can’t see what you’re using it for. This means that a WireGuard VPN won’t necessarily be able to help you bypass firewalls. However, some VPNs that support WireGuard (including NordVPN) provide obfuscated servers, allowing you to hide the fact that you’re using a VPN connection.

• Not integrated into all VPNs. While WireGuard is being widely adopted, not all VPN providers have integrated it into their apps yet. It is still a relatively new protocol, after all. Major players in the space are adopting it, however, and NordVPN’s NordLynx protocol — which provides the fastest VPN speeds currently available — is built on WireGuard. It is also likely that more VPN providers will support WireGuard over time.

• Static IP requirement. Base WireGuard requires pre-assigned static IPs for each peer, lacking dynamic address assignment found in OpenVPN. That means administrators must manually assign and track IP addresses for every client, making it more complex to add new users or manage large deployments. It could also create some privacy concerns since each user's internal VPN IP remains fixed and linked to their public key.

• Privacy considerations. The original WireGuard design stores user IPs in memory (though some implementations, such as NordLynx, address this issue). This can discourage some users from choosing WireGuard as their primary VPN protocol.

What makes WireGuard different from OpenVPN?

While OpenVPN is the most widely used protocol at the moment, WireGuard is a better option across several fronts. For one thing, WireGuard’s smaller codebase makes it easier to implement and audit, with around 4,000 lines of code. Compare that with OpenVPN’s 70,000 lines (or 600,000+ lines when including its OpenSSL dependencies), and you can see why WireGuard has an edge here.

Another advantage for WireGuard in the WireGuard vs. OpenVPN debate is the modern algorithms that the protocol uses. Compared to OpenVPN’s AES encryption, ChaCha20, Poly1305 and other WireGuard’s algorithms are considered more superior in their simplicity and speed, while also maintaining a robust level of encryption, key exchange, and hashing.

WireGuard is also faster than OpenVPN for two reasons. First, WireGuard uses the UDP transport layer to move data, while OpenVPN (despite being UDP compatible) generally defaults to a slower TCP process. As previously discussed, WireGuard also employs more efficient encryption keys, further boosting speed.

OpenVPN can be better for hiding the fact that you’re using a VPN in the first place, but if you use NordVPN’s obfuscated servers, you can use the WireGuard-based NordLynx profile while also obfuscating your VPN connection.

How does WireGuard compare to IKEv2/IPsec?

While IKEv2/IPsec VPN could rival OpenVPN in several areas — offering better speeds and lower CPU usage, for example — the protocols serve different purposes and outweigh each other, depending on the user’s needs.

While WireGuard beats IKEv2/IPsec, in speed, encryption, and the length of the codebase, IKEv2/IPsec offers more configuration options for complex scenarios. And while it’s true that WireGuard is easier to set up, IKEv2/IPsec is way more tested in enterprise environments.

IKEv2/IPsec might be your preferred option if you want to run legacy encryption methods or get maximum compatibility and enterprise features. However, if you’re looking for simplicity and performance, WireGuard is the protocol to choose. Since the majority of people that look for a VPN are likely to pick the most up-to-date encryption possible, judging on that parameter alone, WireGuard is a more preferred choice.

Should you consider using WireGuard for your VPN?

When it comes to the question whether you should use WireGuard for your VPN, the answer is a resounding yes. Not only does it provide stronger encryption and faster connection speeds, but it’s also easy to configure and widely available to anyone that has enough technical knowledge to set up the protocol the way they see fit.

On the other hand, those who’d rather just invest in a VPN with a WireGuard protocol are in luck too. Due to its superiority, WireGuard is available on the top VPN provider apps (including providers like NordVPN). The protocol’s specifications make it a perfect choice for those looking to get themselves a VPN for gaming and other activities that might require a speedy and safe VPN connection.

How to configure the WireGuard protocol

To set up WireGuard on your device, the simplest option is to download the NordVPN application and turn on NordLynx. However, if you want to configure the protocol yourself, you can do so by following the steps below. Here’s how to manually set up WireGuard on Linux, Windows, and other OS.

Setting up WireGuard by using a VPN 

You can skip the manual WireGuard setup by using a VPN service with integrated WireGuard protocol, such as NordVPN’s NordLynx. NordLynx is a protocol founded on WireGuard, but with some added benefits to make browsing even more private and secure. If you are looking to use NordLynx with a router (to make sure that all connected devices benefit from it), your only option currently is the Privacy Hero 2 (with more options coming soon).

Follow these simple steps to get started with NordLynx, the fastest WireGuard-based protocol available:

1. 1.Download the NordVPN app.
2. 2.Log in to your account, or set one up.
3. 3.Open “Settings” and select “Protocol.”
4. 4.Choose “NordLynx” from the protocols available.

Once this process is complete, your VPN will be configured to get all the benefits of WireGuard through the NordLynx protocol, and you’ll enjoy the fastest VPN speeds available.