Inband Timestamping

A method, comprising:

• determining an egress timestamp corresponding to a time at which a first packet is transmitted from a physical interface of a first network entity;
• storing the egress timestamp in a memory associated with the physical interface;
• receiving a second packet at the physical interface;
• retrieving the egress timestamp from the memory based upon the received second packet;
• updating the second packet with the retrieved egress timestamp;
• and
• transmitting the updated second packet from the physical interface on to a network media.

A system, comprising:

• a network physical layer (PHY) configured to be accessed by a central processing unit (CPU) using a host interface, the PHY comprising:
• a physical interface configured to transmit packets to and receive packets from a network medium;
• and
• a timestamp memory,
• and the PHY being further configured to:
• determine an egress timestamp corresponding to a time at which a first packet is transmitted from the physical interface to the network medium;
• store the egress timestamp in the timestamp memory;
• receive at the physical interface a second packet from a second network entity;
• retrieve the egress timestamp from the timestamp memory based upon the received second packet;
• update the second packet with the retrieved egress timestamp;
• and
• provide the updated second packet for protocol processing on the CPU.