CDP stands for Continuous Data Protection which is the technology we use for our internal backups. We are now offering clients limited access to their backup files through web interface. With cdp addon you can see your files backed up on the backup machines and can schedule a restore of any files(s). This is what CDP addon provides on a very minimal cost.
This addon is available for all shared, semi-dedicated, reseller and linux vps hosting accounts (this is not available for windows vps).
If you have a dedicated server you can purchase Data LockBox backup services to use this addon.