With layer 2 bridging, you can have a connection to a VLAN-backed port group or a device, such as a gateway, that resides outside of your NSX-T Data Center deployment. A layer 2 bridge is also useful in a migration scenario, in which you need to split a subnet across physical and virtual workloads.
A layer 2 bridge requires an Edge cluster and an Edge Bridge profile. An Edge Bridge profile specifies which Edge cluster to use for bridging and which Edge transport node acts as the primary and backup bridge. When you configure a segment, you can specify an Edge bridge profile to enable layer 2 bridging.