NetTimeLogic's PTP Tap allows to monitor a single 100Mbit link between two PTP devices. It intercepts the path between two 100Mbit Ethernet ports. It is minimal intrusive (except delay and PHY jitter ~ 50ns). It merges all PTP frames (or all frames depending on configuration) from both sides to a 1000Mbit uplink. In addition it adds to the frame a VSS monitoring trailer which contains the source (side) and a timestamp when the frame was received before forwarding it to the uplink. This timestamp can optionally be synchronized via PTP via fourth port. A tool like Wireshark(TM) or PTP Track Hound(TM) can then be used to analyze the frames and their timely occurrence.
