Can ST 2059-2 Benefit From PTP Version 2.1?

Abstract

With the publication of version 2.0 of the IEEE 1588 Standard for accurate time transfer over packet networks in 2008, the Precision Time Protocol (PTP) quickly became the only viable clock synchronization technology for all application domains relying on ethernet as a transport medium. PTP was deliberately defined in highly generic terms, allowing it to be tailored to application-specific requirements via PTP profiles. The SMPTE ST 2059–2 standard is the PTP profile for the broadcasting industry and a crucial element for any all-IP studio deployment. In 2019, the IEEE published a new version of the IEEE 1588 standard (PTP v2.1), where PTP was enhanced with several interesting optional features aimed primarily at improving the overall reliability of PTP, especially for larger deployments. In this article, we explain all major new features of PTP v2.1 and investigate to what extent broadcasting applications may benefit from adopting them as part of a new version of the ST 2059–2 PTP profile. Specific focus will be put on possible implications with respect to implementation efforts and operating requirements. We analyze whether the overall reliability of PTP can be improved by adding new features such as PTP security or extended monitoring. The high-accuracy extensions to PTP v2.1 will be described together with a rough effort estimate required to develop and deploy products supporting subnanosecond accuracy. The article concludes with a list of recommendations summarizing the benefits of these new features for deploying broadcasting networks at scale.