Unknown Unicast Flood Block Overview

Unknown unicast traffic consists of unicast packets without known destinations. The unknown unicast traffic floods across switches causing unnecessary loops and decreasing network throughput. Unknown Unicast Flood Block (UUFB) blocks the flood of unknown unicast traffic and allows only traffic with known MAC addresses to exit the port. UUFB can be applied on physical ports and Link Aggregation Group (LAG) ports.

Unknown Unicast Flooding Example

Unknown Unicast Flooding Block