Overview: Key features and design philosophy

WireGuard is lauded for its speed and simplicity. It’s designed to be lean and efficient. With just about 4,000 lines of code, it's significantly more concise than OpenVPN, which has around 70,000 lines. This compact codebase makes WireGuard easier to audit and verify for security issues. Fewer lines of code mean fewer places for bugs to hide. 

Efficiency.

WireGuard uses state-of-the-art cryptographic algorithms like ChaCha20 for encryption and Poly1305 for authentication, which are faster and more efficient than the older algorithms used by OpenVPN. This results in quicker connections and higher throughput. 

For example, if you frequently switch networks or use your VPN on mobile devices, you'll notice that WireGuard handles these transitions with minimal interruption. It’s built to manage network changes and roaming seamlessly, which isn’t always the case with OpenVPN.

Ease of configuration.

Unlike OpenVPN, which offers a plethora of configuration options and supports a variety of encryption algorithms, the WireGuard VPN protocol sticks to a single set of protocols. This design choice eliminates the complexity of manual configurations, making WireGuard straightforward and user-friendly. 

WireGuard’s approach to cryptography is also noteworthy. It leverages modern cryptographic primitives like Curve25519 for key exchange, BLAKE2 for hashing, and HKDF for key derivation, which are designed to be secure and efficient. 

WireGuard’s focus on modern, efficient cryptographic methods contrasts with OpenVPN’s flexibility in allowing users to choose from a variety of older and newer algorithms. That flexibility can sometimes lead to misconfigurations and potential security vulnerabilities.

Compatibility

WireGuard supports a wide range of platforms, including Windows, macOS, Linux, Android, and iOS. However, it is still catching up to OpenVPN in terms of widespread adoption and support across all devices and VPN services. OpenVPN has been around longer and is supported by almost every VPN provider out there, which gives it an edge in terms of ubiquity.

Privacy 

WireGuard’s design requires the server to store users’ IP addresses until it reboots, which some see as a privacy drawback. VPN services using WireGuard often implement measures to mitigate this by periodically removing stored IPs, but it's a consideration for those who prioritize complete anonymity. OpenVPN, on the other hand, doesn’t store any user information, making it a better option for those who are highly privacy-conscious.

WireGuard’s key features and design philosophy focus on speed, simplicity, and modern security practices, aiming to provide a lightweight and efficient VPN solution. WireGuard’s performance and simplicity make it an appealing choice for many users.

WireGuard vs OpenVPN: Breaking down the key features & attributes.

Speed

With the ability to achieve throughput rates of 10gbps where OpenVPN struggles to maintain speeds above 100 Mbps, WireGuard easily wins the speed contest. The reasons behind WireGuard's speed advantages are pretty straightforward. 

WireGuard’s lean codebase gives it a streamlined architecture that allows it to process packets faster, resulting in lower latency and higher speeds. On the other hand, OpenVPN's complexity can sometimes lead to slower performance, particularly under high loads.

Moreover, in environments where multiple users are connecting simultaneously, WireGuard tends to handle the traffic more efficiently. Tested in environments with multiple users, WireGuard was able to maintain robust performance levels, showing only a slight degradation. Conversely, OpenVPN exhibited more noticeable slowdowns, making it less ideal for scaling in larger corporate settings.

In practical terms, this means that your team is less likely to experience frustrating slowdowns and can remain productive, whether they're uploading massive files or collaborating through various online tools. The enhanced performance of WireGuard can translate into real-world benefits, such as quicker access to critical resources and a smoother user experience overall.

‍WireGuard's speed not only reduces the downtime but also simplifies troubleshooting. It can handle demanding workloads better than OpenVPN, which is especially useful in remote working scenarios, where a reliable and fast connection is crucial for maintaining business continuity.

CPU and memory usage

WireGuard’s  simplicity translates directly into lower CPU overhead, meaning it can consume only a fraction of CPU resources even under heavy traffic. WireGuard also tends to be frugal in its memory usage, often using just a few megabytes of RAM. This is partly because it operates in the Linux kernel, optimizing memory management and reducing latency.

On the other hand, OpenVPN is robust and highly adaptable but its more extensive codebase inherently demands more CPU power. During peak usage, OpenVPN can significantly increase CPU loads. It’s versatile, no doubt, but that versatility comes at a cost.

OpenVPN also requires more memory. Depending on the configuration, it can easily use up tens of megabytes of RAM, especially when handling multiple connections and complex encryption settings. In the corporate network setting, where dozens or even hundreds of simultaneous connections can occur, these differences become noticeable. 

WireGuard’s leaner codebase and lower resource usage can lead to smoother performance on existing hardware. It’s especially useful if you’re running VPN on devices with limited resources or aiming to maximize efficiency. 

In contrast, while OpenVPN’s higher resource consumption can be managed, it often requires more robust hardware to maintain the same level of performance. This could mean more investment in servers or infrastructure to ensure a seamless experience for all users.

WireGuard’s efficiency in CPU and memory usage makes it a lightweight and responsive solution.

WireGuard sticks to a modern, streamlined set of algorithms. It uses ChaCha20 for encryption and Poly1305 for message authentication. These algorithms are known for their speed and efficiency. ChaCha20, in particular, is designed to work efficiently on devices with varying computational power, which is why WireGuard performs so well on mobile devices.

OpenVPN offers more flexibility with a variety of encryption algorithms. You can choose from well-established ones like AES (Advanced Encryption Standard) or go for newer options like ChaCha20Poly1305. AES, especially in its most popular 256-bit key size, is widely respected for its security and is used globally by various institutions, including government agencies.

Although OpenVPN’s flexibility comes with a certain level of complexity, you enjoy the convenience of selecting different key sizes and modes of operation, such as CBC (Cipher Block Chaining) or GCM (Galois/Counter Mode). For instance, you might opt for AES-256-GCM if you need strong security with good performance, or you could choose AES-128-CBC if you want to balance between security and speed.

In WireGuard, your options are limited toChaCha20 and Poly1305 algorithms. This might seem limiting, but the advantage is a simpler, more auditable codebase. With fewer options to configure, there’s less room for misconfiguration, which enhances security.

OpenVPN's versatility can be a double-edged sword. While it allows you to switch algorithms quickly if a vulnerability is found (like updating from an outdated mode to a more secure one), it also requires more setup and maintenance. In contrast, WireGuard's fixed algorithm choice means you don’t get to switch, but it simplifies the overall implementation.

WireGuard’s use of modern cryptographic primitives keeps the codebase concise, which makes it more secure and user-friendly. OpenVPN’s support for multiple algorithms and its long-standing presence in the security community mean it’s a trusted choice, albeit more complex to configure.

Vulnerability and exploit history

OpenVPN has had some notable vulnerabilities over the years. For instance, CVE-2017-12166 was a vulnerability where OpenVPN, through an unusual combination of events, could allow an attacker to potentially access sensitive data. This was patched swiftly, but it highlighted the complexity of OpenVPN’s codebase, making it more prone to such issues. 

Another example is CVE-2018-7544 which was an input validation failure that could be exploited by a remote attacker to cause a denial of service. OpenVPN’s extensive code and long history mean more opportunities for exploits, though its community is vigilant with patches and updates.

WireGuard, on the other hand, is relatively new and has a much smaller codebase. This has made it less susceptible to security vulnerabilities so far. The simplicity of WireGuard’s design helps in minimizing potential vulnerabilities. For example, a vulnerability like CVE-2019-14899 was primarily related to Linux’s implementation rather than WireGuard itself. WireGuard’s lean code makes it easier to audit and spot potential issues, reducing the attack surface compared to OpenVPN.

OpenVPN’s experience and vigilance in patching, contrasted with WireGuard’s simplicity and emerging reliability, offer different but valuable approaches to securing VPN connections.

Frequency and speed of security updates

Both VPN protocols are open-source, which means they benefit from a community-driven approach to security. However, WireGuard's simplicity gives it a bit of an edge in terms of the speed of rolling out updates. It’s easier for developers to understand the entire codebase quickly, identify issues, and implement fixes without the overhead that comes with a more complex system like OpenVPN.

In real-world scenarios, these differences play out in how each protocol is maintained. WireGuard’s development benefits from rapid iteration and straightforward updates, while OpenVPN relies on a robust, if slower, framework of updates and patches. For example, the addition of new encryption algorithms or protocol adjustments happens more fluidly with WireGuard due to its design philosophy.

While OpenVPN’s longer history provides a well-tested, stable protocol, WireGuard’s modern design allows for faster, more frequent security updates. Both approaches have their merits, but the lean nature of WireGuard can cater to a faster-paced security landscape.

Installation and configuration

Setting up WireGuard and OpenVPN in corporate networks can be quite different experiences. WireGuard is straightforward to install, while OpenVPN tends to be more involved when it comes to installation and configuration. 

Installing OpenVPN usually requires downloading the package from the OpenVPN website unless your system’s package manager has it in the repository. Configuration is where things get trickier. OpenVPN uses a series of configuration files and can require a lot of tweaking. This could mean using tools like `easy-rsa` to simplify the process, but it still adds an extra layer of complexity.

WireGuard’s simplicity really shines in corporate settings where you might have a large number of employees. In contrast, deploying OpenVPN at scale requires a lot of effort. Every client needs its own certificate and key, and these need to be signed by a certificate authority (CA). It’s not impossible, of course, but it can get cumbersome. 

In a corporate environment, if you lean toward ease and speed, WireGuard might be your go-to.

Compatibility with operating systems and devices

OpenVPN is compatible with more operating systems and devices than WireGuard. OpenVPN has been around for a long time, and it's supported on nearly every platform you can think of. 

Whether you're using Windows, macOS, Linux, Android, or iOS, you can bet that OpenVPN will work seamlessly. Most commercial VPN services use OpenVPN too. This makes it a go-to choice for many users who need a reliable and widely-compatible VPN solution.

On the other hand, WireGuard, although newer, has caught up quickly. It also supports multiple platforms, including Windows, macOS, Linux, Android, and iOS.

Even though WireGuard is catching up fast, if you need a VPN solution that works out-of-the-box with an extensive range of devices and operating systems, OpenVPN is the safer bet.

Handling large numbers of connections

WireGuard's leaner codebase directly translates into lower resource usage, in terms of both processing power and additional server infrastructure. This efficiency shines through especially when dealing with many users. OpenVPN tends to consume more CPU resources because of its complex encryption protocols and legacy code, which can become a bottleneck, especially if your servers aren’t top-of-the-line. 

OpenVPN’s initialization phase can take a considerable amount of time, especially as user count scales. WireGuard, however, establishes connections almost instantaneously. In tests that simulated large numbers of connections, WireGuard consistently completed handshakes in a fraction of the time OpenVPN required. This rapid handshake process makes a big difference during peak usage times or when users frequently disconnect and reconnect.

Moreover, in high-latency situations, WireGuard's performance remains stable. In a scenario where users are spread across different geographic locations, WireGuard maintains strong performance with low latency, while OpenVPN struggles, which can lead to noticeable lag and slower data transfer rates.

WireGuard typically handles multiple connections much better than OpenVPN. It’s a practical choice for modern corporate networks looking for performance and scalability.

Support for various network topologies

OpenVPN works well in complex network setups. It works well with NAT (Network Address Translation) and can handle a variety of network types, such as peer-to-peer and client-server architectures. Furthermore, it is highly adaptable when integrating with existing corporate networks that have a lot of moving parts.

WireGuard offers a more streamlined approach. Its simplicity is one of its biggest advantages. It is incredibly easy to set up for point-to-point connections or simple client-to-server topologies. The lean codebase means fewer bugs and faster performance.