The choice between Bridging (TAP) and Routing (TUN) can determine the efficiency and functionality of your OpenVPN setup. While both options allow you to build a virtual private network (VPN), they differ fundamentally in how they handle data and network protocols. By understanding the differences, you can make an informed decision that meets your specific needs.
Key insights
- Bridging (TAP) can transmit all network protocols but is inefficient and limited in scalability.
- Routing (TUN) is faster, requires less bandwidth, but necessitates manual setup for devices on the network.
- The choice between these two modes depends on specific use scenarios and infrastructure.
Step-by-step guide
In this guide, you will learn about the differences between Bridging and Routing and how to configure both in OpenVPN.
Understanding Bridging and Routing
Before diving into configuration, it's important to understand the fundamental differences between Bridging (TAP) and Routing (TUN). Bridging creates a complete tunnel for Ethernet packets, while Routing uses a tunnel for IP packets.
Advantages of Bridging (TAP)
A major advantage of Bridging is the support for any network protocols. This also allows you to use applications like Samba to realize network shares or wake devices from standby mode. This transparency in the target network enables you to utilize broadcast messages as well.
However, Bridging has a downside: it is inefficient. Scalability leaves much to be desired, and the high data overhead due to the low layer (Layer 2) can significantly burden your network, especially over long distances.
Disadvantages of Bridging (TAP)
The disadvantages of Bridging are clear: performance suffers from the high overhead, and there may be delays in data transmission. Ultimately, this means that in a larger network or over long distances, you are inefficient with your bandwidth.
Advantages of Routing (TUN)
In contrast, Routing offers significant advantages. It ensures faster transmission since less overhead is required. This allows you to save bandwidth, which is particularly beneficial in large networks or unstable internet connections.
If you choose Routing, your network benefits from better scalability. However, you must be careful that only IP packets are routed and you cannot process broadcast messages. This means that devices cannot automatically register over the tunnel in the network.
This has a direct impact on device setup; for instance, printers must be added manually rather than being automatically recognized through broadcast messages.
Disadvantages of Routing (TUN)
The limitations of Routing are evident: since no broadcast messages are used, you require additional effort for manual configuration. For example, integrating a printer into your network does not happen automatically.
Conclusion and next steps
Before you move on to the practical steps, here are some recommended links for further information:
- The OpenVPN documentation provides detailed and up-to-date information on the different VPN options.
- Additional resources can be found on openvbn.singsecret.at and wikiopvbn.eu for the German-speaking area.
You are now ready for practical applications: In the upcoming sections, you will learn how to install an OpenVPN server on various clients, including Linux, Mac, and Windows.
Summary – Bridging vs. Routing in OpenVPN: Your comprehensive guide
Understanding Bridging and Routing in OpenVPN is crucial for the optimal functionality of your network. You should weigh the pros and cons of both approaches to find the right solution for your needs.
Frequently Asked Questions
What is the difference between Bridging and Routing in OpenVPN?Bridging transmits Ethernet packets (Layer 2), while Routing can process IP packets (Layer 3).
What advantages does Bridging (TAP) offer?Bridging allows the use of any network protocols and supports broadcast messages.
Does Routing (TUN) have disadvantages?Yes, it cannot process broadcast messages, meaning some devices must be added manually.
How does the efficiency of Bridging affect network capacity?Bridging has a high overhead, reducing efficiency and limiting scalability.
When should I use Routing (TUN)?If you want a faster connection and better control over your bandwidth, Routing is the better choice.
