VPN vs. SD-WAN tunnels

VPN vs. SD-WAN tunnels

Want to invest in a virtual private network or SD-WAN tunnel but don’t know which one to use? It’s important to realize these technologies have many differences and serve unique purposes in your business environment. This guide will teach you more and help you make the right purchasing decision for your business. 

Virtual private networks explained

A virtual private network (VPN) creates a secure connection between a device — say your computer — and a network via the internet. It can also connect two separate networks. The great thing about a VPN is that it encrypts your data, meaning servers that intercept it don’t know your identity or location. 

VPNs provide protection when you are on the internet. For example, you can avoid third parties, including your internet service provider (ISP), from knowing which websites you visit. VPNs transfer your data to a website through a network of servers maintained by your VPN provider. So your ISP will only see that your data has come from a VPN server — not your device. 

There are several use cases for VPNs. The first is remote access, where people working away from the office can access their company’s private network. For example, a remote worker in a coffee shop can use a VPN to connect to a private network instead of a local Wi-Fi hotspot, improving security and confidentiality. 

Another use case for VPNs is site-to-site connectivity, which facilitates a connection between two or more networks, such as a corporation network and a branch office network. Again, this protects sensitive data shared over the internet. 

SD-WAN tunnels explained

An SD-WAN tunnel or overlay tunnel is a communication pathway that exists between data centers, cloud computing services, or other endpoints. It is part of the software-defined wide-area networking (SD-WAN) architecture, which connects businesses in separate locations via broadband internet, 4G LTE, or another wide-area network (WAN). 

SD-WAN tunnels enable two endpoints to communicate with one another. WAN interfaces are located at both ends of a tunnel and exchange information with the underlay network layer in SD-WAN architecture to allow this communication. 

SD-WAN tunnels make connectivity more efficient and agile. They use algorithms to guide IP packets between WAN paths, increasing the reliability and performance of network connections in SD-WAN architecture. They can also aggregate two or more WAN resources simultaneously. 

What are the differences between VPN and SD-WAN tunnels?

While VPNs and SD-WAN tunnels might make up part of your networking architecture, that’s the end of their similarities. Here are some differences between these technologies.

Configuration and management

A VPN is a network, while an SD-WAN tunnel is a component of SD-WAN architecture, so it’s difficult to compare the two. Manually configuring and managing both requires a steep learning curve; however, VPN and SD-WAN vendors allow you to use these technologies without any networking experience. Vendors take care of configuration and management so you don’t have to. 

Handling traffic

VPNs scramble network traffic with high-level encryption, protecting your identity on the internet. SD-WAN tunnels only allow two endpoints to communicate with one another so aren’t responsible for handling traffic. However, SD-WAN architecture as a whole uses a central control pane to route traffic to different destinations based on user policies and algorithms. For example, SD-WAN can determine the best route for application traffic from historical performance data, reducing the likelihood of network outages that can impact your business. 


Again, it’s easier to compare the costs of VPNs with those of SD-WAN architecture as SD-WAN tunnels are just one component of this technology. Generally speaking, VPNs are more cost-effective than SD-WAN because they have a more straightforward design. However, both can provide a significant return on investment if they fulfill your business use case over time. For example, a VPN keeps data safe when remote employees connect to their company’s private network, which can be priceless. 


You can’t scale an SD-WAN tunnel, but you can certainly expand SD-WAN architecture to meet your business needs. For instance, this technology can accommodate new devices as your company grows. The only way you can increase the scope of a VPN is by adding new users to the network, so SD-WAN is inherently more scalable. 


Many VPN providers allow you to view metrics about performance, reliability, and other functions. For instance, you can learn the quality of your VPN connection and how many people use it at a particular time. SD-WAN vendors might also provide metrics, allowing you to track 

latency, packet loss, and other variables at regular intervals. You might also be able to learn about the performance of SD-WAN tunnels specifically. However, vendors don’t usually make insights about individual components of SD-WAN available and instead provide insights about this technology as a whole. 

VPN benefits

The advantages of a virtual private network include enhanced security, remote access, and compatibility with existing infrastructure in your business.

Increased security

VPNs encrypt your data so you can enjoy the internet anonymously. They do this using public and private keys, ensuring only you can access your browsing history. There are several use cases for investing in a VPN for security. For example, you might want to use this technology to prevent hackers from seeing your passwords and usernames for online banks, email services, and social media accounts. 

Remote access

Remote workers often use VPNs when away from the office. A VPN will allow them to connect to their company’s private network wherever they are in the world. If you have remote workers in your organization, you can use a VPN to keep all your employees on the same network. 

Compatibility with infrastructure

Another great thing about VPNs is that they provide anonymity and remote access via different infrastructure types. This includes hardware such as computers, laptops, smartphones, tablets, smart TVs, and even video game consoles. That means you don’t need to purchase new equipment to get value from a VPN. 

SD-WAN tunnel benefits 

The advantages of SD-WAN tunnels include dynamic path selection, improved application performance, and centralized management. 

Dynamic path selection 

As mentioned, SD-WAN tunnels don’t specifically handle traffic. However, SD-WAN architecture can improve the flow of traffic with dynamic path selection, which determines the best traffic route for applications based on algorithms and user policies. SD-WAN can also keep your network functioning with automatic failover, which suggests traffic takes a different path when a failure occurs. 

Improved application performance

Again, SD-WAN tunnels won’t enhance application performance directly. However, by choosing the right traffic path for an application, SD-WAN architecture can certainly improve the performance of an app. For example, an app can continue to function even in periods of high traffic and network congestion. SD-WAN can also prioritize traffic for your most important apps, which will receive networking resources before less important apps. 

Centralized management

SD-WAN vendors provide a central control pane that allows you to monitor different components of SD-WAN architecture, including tunnels. You can also define user policies for SD-WAN from this console rather than using several tools, reducing the complexities of network management. 

Should you choose a VPN or SD-WAN tunnel for your business?

VPN and SD-WAN tunnels serve different purposes. The former creates a secure connection between a device and the internet, while the latter is a communication pathway in SD-WAN architecture that provides connectivity solutions. This article goes into great detail about the differences between these technologies. 

There are other factors to consider when choosing between VPN and SD-WAN tunnels. Ultimately, the technology you choose depends on your use case, company size, networking requirements, and the future growth of your organization. It’s also important to note that SD-WAN architecture, which includes SD-WAN tunnels, can be more expensive than a VPN, so you should evaluate your budget as you make a purchasing decision. That said, both technologies can provide a return on your investment if they provide your company with value. 

Also, think about the scenarios where you might use a VPN or SD-WAN tunnel. A virtual private network is best suited for remote work set-ups or protecting your identity on the internet. An SD-WAN tunnel, however, helps you if you want two endpoints in your SD-WAN architecture to communicate with one another.

Further reading

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