Comparison of OpenVPN and Outline Speeds

Let’s compare the speeds of popular solutions like OpenVPN and OutlineVPN. Both solutions are open source, which allows us to install them on our VPS servers and conduct clean tests, ruling out factors such as server channel congestion and third-party loads.

Often, when using VPN services, we have some problems with the speed. So we may notice that when we connect to a VPN, the speed is significantly slower than that provided by our internet providers (LTE or Wi-Fi).

Internet speeds can slow down when using a VPN for several reasons. Firstly, VPN connect servers may be a considerable distance from your physical location, which increases the time it takes to transfer data between your device and the server. This adds latency (or ping) and can reduce the overall throughput of the access connection.

In addition, the data encryption and decryption process that the fastest VPN servers perform also adds to your device's CPU load. The more complex the encryption methods used, the more time and resources this process takes, which can result in slower internet speeds.

Let's compare the speed of such popular solutions as OpenVPN and OutlineVPN. Why them, exactly? The answer is simple: both of these solutions are open source, which allows us to install them on our VPS server and perform clean tests that will exclude the influence of such factors as server channel congestion and third-party load.

Before starting the test, let's conditionally decide that the main difference between Outline and OpenVPN speed is that Outline is a more straightforward and more user-friendly tool for creating your own VPN network, which is aimed at inexperienced users and provides easy installation and management.

At the same time, OpenVPN server is a more robust and customizable open-source VPN protocol, which offers more control and flexibility but requires more in-depth knowledge for configuration.

Test bench based on OS: CentOS Linux

Provider: OVH

VPS resources:

1GB RAM.

1 CPU core

Firstly, let's find out the real channel speed on VPS using the speed test utility:

Results:

Server: Skymote.net - Paris (id: 59312)

ISP: OVH SAS

Download: 98.12 Mbps (data used: 95.2 MB)

115.68 ms (jitter: 34.35ms, low: 26.87ms, high: 166.44ms)

Upload: 97.87 Mbps (data used: 93.8 MB)

117.75 ms (jitter: 36.24ms, low: 26.99ms, high: 166.94ms)

Result link:

https://www.speedtest.net/result/c/9588a560-8a84-4024-981a-d1faa6e530d7

Now we know what maximum speed the channel can provide on our test VPS server, and we can start testing VPN.

Configurations for Outline and OpenVPN are already installed on the test VPS.

We will test via LTE mobile internet, so let's test LTE network speed on our device:

Download: 79 Mbps

Upload: 25 Mbps

Ping: 82 ms

Download latency: 971

Upload latency: 323

Jitter: 3 ms

https://www.speedtest.net/result/i/5817995420

Connect to Outline on our test VPS server and repeat the test:

Download: 75 Mbps

Upload: 32 Mbps

Ping: 139 ms

Download latency: 669

Upload latency: 435

Jitter: 1.7 ms

https://www.speedtest.net/result/i/5817999647

Then we connect to OpenVPN on our test VPS server and repeat the test:

Download: 20 Mbps

Upload: 3 Mbps

Ping: 231 ms

Download latency: 1977

Upload latency: 651

Jitter: 9.8 ms

https://www.speedtest.net/result/i/5818001620

By the way, OpenVPN uses the following configuration:

cipher AES-128-CBC

auth SHA256

comp-lzo

proto tcp

According to the results of the test and the Outline VPN review, we can make the following table for clarity:

As you can see, both from the table above and the VPN reviews, Outline is almost 4 times faster in terms of data download speed and nearly 10 times faster in terms of data upload speed. The result is reasonably expected. The reasons for this are shown at the very beginning of the article, and now you can see how much encryption has a substantial impact on speed.