Apparatuses, systems, and methods for accurately measuring packet propagation delays through usb retimers

A method comprising:

• receiving a data block and a timestamp for the data block from an upstream device with a receiver of a retimer apparatus;
• storing the data block and the timestamp for transmittal in a buffer of the retimer apparatus;
• modifying the timestamp to generate a modified timestamp including a time from a receipt of a first portion of the data block in the buffer until a transmittal of the first portion of the data block from the buffer;
• and
• transmitting the data block and the modified timestamp to a downstream device with a transmitter of the retimer apparatus.

An apparatus comprising:

• a hardware processor;
• a host;
• and
• a retimer apparatus comprising:
• a receiver to receive a data block and a timestamp for the data block from the host;
• a buffer to store the data block and the timestamp for transmittal;
• a controller to modify the timestamp to generate a modified timestamp that includes a time from a receipt of a first portion of the data block in the buffer until a transmittal of the first portion of the data block from the buffer;
• and
• a transmitter to transmit the data block and the modified timestamp to a downstream device.