What is the difference between VBB and Dump backup type?

Greetings,

Using BE 2010 to backup NDMP data to a Data Domain appliance. NDMP backup type setting in the backup policy had been set to VBB. We recently installed DD Boost. Backups began to fail. Changed NDMP backup type setting to DUMP. Backups are successful. Is there a certain way to configure an NDMP backup to use DD Boost? What is the difference between VBB and DUMP?

Thanks.

GN