End-to-End Transparent Clocks Between Master And Slave

PTP defines the notion of End-to-end transparent clocks which do not participate in time synchronization with master clock.

Rather, they simply accumulate the residence time of PTP event messages such as Sync/DelayReq that transit the switch. The residence time is updated in the CorrectionField of these messages.

The transit delay in the link between the hops are not accounted in the CorrectionField by the End-to-end transparent clocks.