While many universities in South Africa offer VPN services, they're often focused on providing secure access back to your campus rather than simply protecting your Internet access. eduVPN, on the other hand, aims to provide you secure Internet access that's fast and reliable. However, if your institution uses eduVPN internally, it can also give you access to protected resources on your institution's network such as storage, administrative systems, etc.
Like eduroam, eduVPN is developed by the international research and education community, and provided by national research and education networks around the world. Through reciprocal arrangements, with eduVPN you have the opportunity to choose which country you are in and access the Internet securely using a network close to you, without having to tunnel it back all the way to South Africa. This makes eduVPN especially useful for people who travel internationally.