designated subnet bandwidth manager (DSBM)
Designated Subnet Bandwidth Manager (DSBM) is a concept for improving the quality of service in IP networks. A DSBM can manage multiple Layer 2 segments simultaneously. A segment whose resources are managed by a Designated Subnet Bandwidth Manager (DSBM) is called a managed segment. A DSBM client is a network unit that sends data over a segment managed by a DSBM.