Patent ID: 8644350

Claim:
A method of determining a time of transit of a packet over a communication network, comprising: providing a physical layer portion of a slave communication device a packet including a value indicating an approximate time of transmission of the packet by the slave communication device; having the physical layer portion of the slave communication device insert a correction value into the packet, the correction value indicating a difference between the approximate time of transmission and an actual time of transmission of the packet by the slave communication device; transmitting, by the physical layer portion of the slave communication device, the packet to a master communication device; receiving, by the slave communication device, a responsive packet from the master communication device, the responsive packet including a time value indicating a time of receipt of the packet by the master communication device and an indication of the correction value; and calculating the time of transit by the packet over the communication network using the approximate time of transmission, the indication of the correction value, and the time of receipt by the master communication device.