When looking at the VPG details you will see that the ZVM reports back the following storage values, these values are also used in various reports and API responses...
Protected / Protected Data / Provisioned Space
Protected Data aka Provisioned Space in VMware is calculated by Zerto by summing the VMs committed and uncommitted space as reported by the source vCenter.
To verify this you can web-browse to the vCenter mob browser using the following URL format
where vm-XXX is replaced with the corresponding VM ID. From the results browse to the summary | storage key to see the following result format.
Note. The figures from the VMware Committed and Uncommitted cells is in bytes, to obtain the value in GB divide the byte value by 1.074e+9
Used Data / Used Space
Used Data aka Used Space in VMware is calculated by Zerto directly from the sum of all VMs committed space as reported by the source vCenter.
To verify use the same mob browser results as shown in the Protected section.
Note. The figures from the VMware Committed cell is in bytes, to obtain the value in GB divide the byte value by 1.074e+9
Recovery Storage is calculated by Zerto from the VPGs Used Storage + the used journal storage for all protected VMs within the VPG.