hwdot1sMstiPortPriority 1.3.6.1.4.1.43.45.1.2.23.1.14.20.1.3

The value of the priority field which is contained in the first (in network byte order) four bits of the (2 octet long) Port ID. The other octet of the Port ID is given by the value of mstiPortIndex. And step of 16