The data we save for Visitor Insights (VI) are:
- sid, random session id
- sst, sessions start time
- sis, session interaction step
- rv, returning visitor
- pa_enabled, which states if the tool works in their browser
The session ID, sid, is randomly generated and it is unique for the domain the script is loaded on, the session ID is regenerated if the next page load occurs after more than 30 minutes.
The random session ID means that we can not track if the visitor are on multiple sites using VI.
We track if the visitor is returning by looking for an expired session and set the rv, returning visitor, to 1. The old session ID is not used, we simply mark that they are returning. The rv value is not set if more than 30 days has passed.