For live software-based systems such as those defined by the EBU in their Dynamic Media Facility (DMF) reference architecture there is the capability for media functions to process data asynchronously, only re-synchronising between elemental flows where required. We can leverage this to enable significant benefits both in terms of latency and efficiency of compute resource.

To achieve this, there is a need for an ecosystem-based approach to time labelling which has benefits for both identity and synchronisation of IP based media flows and elements.

It is possible today to build a system that uses existing standards to provide highly accurate absolute timestamps end-to-end from media origination all the way through to end user playout, including asynchronous workflows such as using DMF.

In an ideal deployment each sample point is well defined in absolute time and each media frame is uniquely tagged using a timecode address that is translatable back to immutable timestamps in an IP based sysyem.

This paper will explore the methods and constraints of building an end-to-end asynchronous distributed media workflows and in particular the relationships between all the current timing related specifications such as GNSS, PTP, ST 2059-1, ST12M, ST 309 and other possible alternatives such as MISB ST 0604.6 and MPEG TEMI (H222.0 Annex U).