tmnxPtpPeerLastRxPortEncapValue 1.3.6.1.4.1.6527.3.1.2.74.2.3.1.20

The value of tmnxPtpPeerLastRxPortEncapValue along with tmnxPtpPeerLastRxPortId and tmnxPtpPeerLastRxPortEncapType indicates the last port used to receive PTP packets from the PTP peer.