This feature allows you to enable SSL for your surveys. Secure socket layer links (SSL) encrypt the online survey and data during respondents’ sessions (the same level of security as online banks).
This is incredibly useful if you are collecting sensitive information (contact, health, financial information, etc), as you can add an extra layer of security to the data that’s being transferred.
Secure links can be sent out using the default web link and also using the email invite tool.
Here is the video tutorial on this topic: