Nintendo has added two-factor authentication. If you currently own a Nintendo Switch and/or a 3DS, you will need to set up a two-factor authentication. Polygon is reporting that Nintendo Network, which is the portal for users on both devices, implemented this set-up effective immediately.
Now, the two-factor process runs through Google Authenticator. That will mean you can only use this through a mobile device, either Android or iOS. That will mean that every new or normal login to the Nintendo Network will have to pass through the Google Authenticator.
To enable the feature, you need to login and select the “sign-in and security settings” tab. Looking toward the bottom, you will be to select the option to enable two-step verification.
Many services offer the two-step authentication option, but very few require it. It is an additional layer of security for the service and the consumer. This will prevent any unauthorized access to your services but it does not make it fool-proof.