The value of tmnxPtpMasterClockLastTransType indicates the type of transport that was last used by the parent clock. When the value is 'none (1)', the local clock was last used as the parent clock. When the value is 'udpIp (2)', tmnxPtpMasterClockLastIpAddrType and tmnxPtpMasterClockLastIpAddress contain information about the parent clock that was last used. When the value is 'ethernet (3)', tmnxPtpMasterClockLastEthPort and tmnxPtpMasterClockLastMacAddress contain information about the parent clock that was last used.