VPNs use a variety of different VPN focused protocols to deal with your Internet traffic. Some have just one built-in and there is no choice but others, Like Surfshark, allow you to choose from multiple options.
Don’t let this put you off as the difference between them is easily explained to allow you to make an informed choice as to what protocol to use.
OpenVPN is an open-source protocol which is actively being updated and comes in two flavours – UDP and TCP. It’s fast, secure, and often works best for long-distance connections or desktop operating systems. With Surfshark you can choose between UDP and TCP to suit your individual preferences.
IKEv2 (short for Internet Key Exchange version 2) is a fast and secure protocol that tends to work best when the server you’re connecting to is physically nearby. It was developed by Cisco and Microsoft security engineers and it is very popular among mobile users. I find this gives me the best connection speeds on my Android smartphone and tablet.
Surfshark also has its own protocol for bypassing censorship and VPN blocking technologies by countries such as China and Russia. Shadowsocks is an encrypted proxy that was designed specifically to help people overcome the restrictions of the so-called Great Firewall of China.
It works great for that purpose, but if you are not in a restricted country, you’re better off using either OpenVPN or IKEv2.