IP-VFC - PTP

The Precision Time Protocol (PTP) is a protocol used to synchronize clocks throughout a computer network. On a local area network, it achieves clock accuracy in the sub-microsecond range, making it suitable for measurement and control systems.

ST 2110 is bidirectional, meaning that separate signal paths no longer need to be constructed to distribute sync signals. Instead, each elementary stream (video, audio and ancillary) can be broken apart. This is useful for a Disguise system, since we are only requiring the output of video.

Each elementary stream of video, audio and ancillary is then timestamped using PTP. This enables high levels of frame synchronisation as a common timecode base can be shared to each stream to the nanosecond.

This is important when implementing an IP-based video infrastructure because switchers, routers and other network infrastructure all increase latency within a system.

Genlock is enabled from the IP-VFC using PTP. This means that if users wanted to output a video signal from the 25Gb port or SFP and wanted it locked to PTP, this could be enabled without the need for genlock.

The IP-VFC card uses the SMPTE 2059-2 profile for PTP, which is used with devices configured to operate using ST 2110 for video and audio. The PTP operating modes that the IP-VFC card supports are multicast and mixed.