Electronic devices coupled to a network may exchange messages containing time-of-day information synchronization of the internal clocks. The information exchanged may include the instant at which a message leaves the electronic device. Discussed herein are methods and systems that allow 1-step timestamping of messages containing time-of-day information. The 1-step timestamping methods and systems may reduce the impact of non-deterministic time delays in the transmit path (e.g., encryption, expansion, inclusion of tags), and may improve the accuracy of the time-of-day information of the packets. For example, systems and methods may allow accurate 1-step timestamping of IEEE 1588 Precision Time Protocol packets with the uncertainty of delays from MACSec encryption or other security mechanisms. Some embodiments employ estimation non-deterministic delay of previously transmitted packets to estimate the state of the transmit path. Some embodiments include communication channels to allow circuitry in transmit path to report the state.