This read-only value is the incoming-direction counterpart to lportOutAllocbwQoS1, reporting bandwidth currently allocated to active inbound QoS Class 1 connections on this port. An admin checks this specifically to see real inbound commitment for the highest-priority class, relevant when inbound and outbound voice or CBR traffic loads on the port differ significantly. For example, a port aggregating voice traffic from many remote sites toward a central PBX would show most of its class-1 commitment in lportInAllocbwQoS1 rather than the outgoing equivalent, since the bulk of that traffic flows inbound toward the aggregation point.