Patent ID: 8738792

Claim:
A method of exchanging messages for facilitating synchronization of processing units of a timing network, the method comprising: receiving an exchange time parameters (XTP) message command at a second processing unit generated by a first processing unit, the XTP message command including a message command transmit timestamp field set by the first processing unit and a message command receive timestamp field unset by the first processing unit; setting the message command receive timestamp field in the XTP message command with the time that the XTP message command is received at the second processing unit; and generating at the second processing unit an XTP message response to be sent to the first processing unit, the XTP message response including the message command transmit timestamp set by the first processing unit and the message command receive timestamp set by the second processing unit obtained from the XTP message command; wherein the XTP message command further comprises a message header dependent on a type of data link used to implement a server time protocol link between the first processing unit and the second processing unit, and a coordinated timing network (CTN) identifier of a timing network to which the first processing unit belongs; wherein the XTP message command is transmitted to the second processing unit over the server time protocol link, and the message command transmit time stamp field is set by the first processing unit using a current time of day clock of the first processing unit, and is set immediately prior to transmitting of the XTP message command; and wherein generating the XTP message response at the second processing unit comprises checking whether the CTN identifier received with the XTP message command matches a CTN identifier of a timing network to which the second processing unit belongs.