First of all professionally there is no difference between post graduatation in business management[pgbm], post graudutation diploma in business management[pgdbm], and mba degree.

technically an institute afflilated with an university gives an mba degree like fms,jbims and autonomous institutes give diploma in management [pgbm,pgdbm] like iims,iift,mdi xlri etc.

hence ur future career prospects depends on the reputation of the institute rather than on the degree or diploma given by it.