Client-side storage used by RUM JS

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Overview

In order to support certain features, Catchpoint RUM utilizes Local Storage under each unique hostname. When a browser does not support the Web Storage API, the Catchpoint RUM tag falls back to using Cookie-based storage. The value stored in Local Storage, or the cookie, is simply used to ensure we track the necessary data for the reporting of the performance a user has during a session on the website, and is not associated with any PII (personally identifiable information). Learn about our commitment to data security and integrity

Storage

If the Web Storage API is supported, Catchpoint RUM stores client-side data under hostname for the site using the key "_CG". Otherwise it uses a cookie called "_CG". Client-side data consists of the following:

  • User ID (saved as "u"): A random unique ID to ensure we know the count of unique users, and also to display the session data in Catchpoint's Analysis tools. This ID is not mapped to any PII; it is simply a unique random number assigned to the site visitor. A different ID is generated per hostname, so subdomain.site.com and www.site.com would be tracked under separate IDs, and there is no means to track user behavior across different domains and subdomains.
  • Session ID (saved as "s"): Another unique number generated to track the active session of the user. This is needed to derive the number of visits or session a user has, and average pageviews per visit (session). This number is regenerated every time the session activity timestamp is older than 30 minutes.
  • Session Time (saved as "t"): The timestamp when the user last navigated during the current session. If the user is not active for more than 30 minutes, a new Session Time and Session ID is generated upon the next navigation by the user.
  • Page View Count (saved as "c"): The number of times any page has been visited during the active session. This is set to 0 when the Session ID is created and incremented by one each time a page is viewed during the session. This is used to determine the Bounce rate (visits with only a single page view).
  • UrlCheckSum (saved as "k"): The checksum for the last page URL visited during the active or most recent session.
  • Post Flag (saved as "f"): Internally used by the system to determine whether the user is in the sample to be tracked, depending on the app configuration. Indicates whether Catchpoint should post the data or not.

This entry in the cookie or local storage should never been modified by any script on the website, or it will result in bad data collected and analyzed. This information is provided just for knowledge, and to assure you that no PII is ever stored or used.