An existing cloud account with a provider that supports the WebDAV protocol is required.
There are many such providers: Free, privacy compliant, with focus on support, using open source software...
Search the Internet or take a look at the cloud providers that are listed in the following Add dialog.
The passwords for the cloud providers are encrypted with the PEA password and then stored.
A directory named PeaFactory is created in the cloud and only this directory is accessed.
When the same calendar file is opened locally and in the cloud, the content is synchronized.