Breaking barriers in synchronization: insights from ITSF 2024

When it comes to precision timing, I often see people approach it from one of two distinct perspectives: those who are sceptical about achieving performance improvements without needing major trade-offs, and those who are optimistic and pragmatic, addressing each issue systematically with the belief that the benefits will ultimately be realized.

Following this year’s ITSF conference, I’m firmly in the optimist camp. That’s because real data is now available which demonstrates robust, real-world timing performance and provides a clearer understanding of the benefits, issues, and potential solutions to challenges such as ‘timing in the last inch.’*

As the timing and sync community continues to grow and share new viewpoints, the team at Calnex left ITSF inspired to push even further in supporting precision timing deployments across a broad range of applications.

Imagine a world where connectivity is as boundless as the sky. A world where remote villages have access to the same digital opportunities as bustling cities. A world where IoT devices can seamlessly communicate across vast distances. This vision is becoming a reality thanks to the integration of Non-Terrestrial Networks (NTNs) and Next-Generation Radio Access Networks (NG-RANs).

The push for standardization

Standardization remains a hot topic, with a focus on maintaining consistency while still allowing flexibility for initiatives that may not yet have established standards. There is a growing trend towards aligning multiple standards for related topics, with individual standards adding context for their specific use cases. I think this makes sense. After all, trying to create “one standard to rule them all” never really works.

Optical module performance has recently been a focus for Calnex (as a test and measurement vendor), along with many of our colleagues in metrology and at equipment manufacturers. The presentation from Calnex’s Stefano Ruffini highlighted the approach taken in the Mobile Optical Pluggables Alliance (MOPA) and aspects of this are being considered by bodies such as ITU-T and SNIA. What really stood out at the event was seeing direct support for such standardization from Telecoms Network Operators – a key step to wider useability and acceptance.

Another standout topic was multi-vendor time synchronization (one of the advantages of a standards-based approach being the ability to bring multiple compliant solutions together from discrete vendors). EANTC presented “Industry-First Multi-Vendor Time Synchronization Test Results: Class-C/D Clocks at Work in Open RAN Scenarios”, highlighting the progress and challenges in this area. During the Q&A, there were some interesting discussions on reporting from such tests – high precision tests such as ITU-T G.8273.2 Class-D cTE can grab attention, but it is important to consider that this is only one aspect of robust network timing. For example, timing performance in the event of network rearrangements (transients) or a device’s noise tolerance capability is equally important, and all parties agreed that support from the industry should always be considered in parallel.

Performance monitoring also got its moment in the spotlight, with almost an entire session of talks dedicated to the topic, covering both theoretical and practical applications of advanced OAM and monitoring in time synchronization networks. There were multiple examples from Network Operators actively demonstrating how monitoring tools will be key to delivering robust synchronization in the future. As such, current, developing and future standards initiatives were referenced, including recent additions to ITU-T G.8275.1 Annex K, G and F as well as O-RAN X-haul transport Annex H and ITU-T G.781 – all offering practical options to solve real-world challenges.

An ever-expanding scope for sync

This year’s ITSF conference struck a balance between commercial insights and technical depth. The sessions allowed participants to gain a comprehensive view of the precision timing landscape, from standardization efforts to the practical applications of synchronization technologies across various sectors. One of the recurring themes during breaks and after-hours chats was bridging the gap between theory and practice. In short, people weren’t just talking about ideas; they were ready to implement them.

Highlights from various industry sectors include:

• Defence: For the first time, a session was dedicated entirely to the defence sector, emphasizing the critical need for time synchronization in various use cases including requirements during combat situations. The session highlighted the importance of timing as the foundation for everything from position and navigation to broader operational needs.
• Wireless TSN: Discussions on ensuring accuracy and reliability for industrial applications, with a new focus on synchronization over 5G.
• Data Centers: Continued interest in synchronization in data centers, with Nvidia and Meta sharing their experiences optimizing and debugging GPU AI clusters.
• Automotive: Discussions on automotive standards and requirements, with a focus on timing distribution over heterogeneous in-vehicle networks.

A special moment

Once again, Calnex was proud to sponsor the Gala Dinner, which featured the presentation of the ITSF Time Lord award to Patrizia Tavella, director of the time department at BIPM. A very worthy winner and a very entertaining after-dinner speaker – congratulations Patrizia!

Final thoughts

ITSF 2024 showed just how dynamic the field of precision timing is right now. With real data supporting improved performance and a concerted effort towards standardization, the future looks bright. Collaboration across sectors and the focus on addressing specific use cases ensure that precision timing will continue to evolve, breaking new barriers and opening up exciting possibilities for a wide range of applications.

*A term I still remember from the presentation Timing in cyber-physical systems: The last inch problem  – at ISPCS 2015! We’re getting there….