Symmetrical broadband and mobile data plans provide Internet connectivity with identical upstream and downstream data transfer speeds. This means data is uploaded from your device to your Internet service provider (ISP) at the same speed as data is downloaded from your ISP to your device.
Using a symmetrical Internet connection is beneficial if you transfer large amounts of data from your devices to your ISP. This is the case when, for example, you upload videos to Youtube or other video streaming services, or when you save or backup data to cloud-based storage.
Asymmetrical Internet connections, on the other hand, have upload speeds which are lower (typically much lower) than their download speeds.
In Switzerland, many broadband service providers offer symmetrical connections. Symmetrical broadband plans have become the norm for optical fiber connections. Note: Some connections marketed as optical fiber connections by Swisscom, UPC and other service providers are not “true” optical fiber connections.
More on this topic:
Asymmetrical Internet connections explained
Swiss broadband comparison