It is no secret that technology has moved forward leaps and bounds over the past ten years, at such a rapid pace it is difficult to keep up with the Jones'. There was a time when a camera was bulky, had to be carried around in its own bag, and had an assortment of lenses varying in length and weight, whereas now it all fits in your pocket and even makes phone calls and email!!
5G technology is opening up the world of innovation and enabling more and more advances in technology for industries such as Smart cities/cars, smart grids, IoT, automation, and much, much, more. However, there is a little unsung hero that is crucial to driving this innovation and that is accurate time. High-accuracy timekeeping is not a new concept but the demand from applications and use cases has made this niche technology a superhero of the modern world. Although timing in 5G has moved forward from the days of dropped calls between cells the consequences of poor timing in 5G have much greater effects than before.
Although 5G is working through the complications of accurate timekeeping the finance industry has been working with this problem for several years, with regulations such as MiFID II in Europe and similar compliance rules in the rest of the world it is imperative that clock sync is in place.
To date, many organisations have used open-source technology such as ptp4l or LinuxPTP to varying degrees of success to achieve the levels of compliance required under these regulations (100 microseconds, 1 millisecond, and 1 second for MiFID II). One of the core challenges imposed is the requirement to evidence traceability.
The main challenge in high-accuracy timekeeping is ensuring what is referred to as Traceability. This is a statement on how well can you trust that your time is "the time". A simple example is you check your watch and see that it is 12:00, you look up and your laptop is 12:01, which one is right?
You may be thinking does it really matter its all pretty much midday, you would be correct if you were waiting for a bus that arrived at 12:05 but when you need to synchronise devices to nanosecond accuracy (1 billionth of a second), it is vital that you know that your source of time is "the time", and not just the same, but the same across all devices.
This is why at Timebeat we have developed the most comprehensive clock sync and timekeeping monitoring platforms. Our software not only focuses on the all-important capability to provide nanosecond level synchronisation but the ability to monitor and visualise at every moment for any device.
Our UTC Verification projects enable our customers to be 100% confident in their timing solution. Unlike alternative solutions Timebeat doesn't solely rely on BMCA (Best Master Clock Algorithm), in fact, we usually recommend using our MSSA (Multi-Source Selection Algorithm), as this provides greater resiliency and stability to the entire timing network not just the individual end client. It is the ability of our MSSA that makes it possible to conduct UTC Source verification primarily in software with very little additional hardware to burn a hole in your pocket.
To understand the MSSA and UTC verification the below details a section from a recent white paper we produced on the topic.
The design
For the proof of concept, a simple off-the-shelf GPSDO clock was purchased (~£150) and a GNSS splitter was used to enable both the GPSDO and the 1u grandmaster clock to utilise the GNSS feed, on the assumption this was stable, protect
ed and a reliable source of UTC. The GPSDO much like the grandmaster clock can accurately synchronise to UTC within several nanoseconds, with the primary difference in basic capabilities between devices being that the GPSDO does not have substantial holdover capabilities or enterprise features, which for the purposes of this solution was not a necessity or criteria for success.
The GPSDO was capable of providing outputs of NMEA via a serial cable, 1PPS, and 10Mhz, for the purpose of this solution 1PPS was the output used with supporting information provided via NMEA. A micro server was the commodity hardware of choice which would be used as our “mimic” end node. There were several options for network cards to be used, however, for this study a Mellanox Connect X-6 was used as this had two 1PPS interfaces on the card. Although only one 1PPS interface is required for the solution to work it was viewed that a second 1PPS interface may come in useful for confirming results with external test equipment.
The GPSDO is connected to the microserver and is the primary source of UTC for the device. Timebeat Enterprise was installed on the microserver to operate as the software synchronisation platform. Timebeat, unlike many other PTP/PPS synchronisation solutions, has many advanced features which makes it the only viable software option to make this possible.
Timebeat synchronises network interfaces and the system clock in one handy application, also logging data to a centralised database. This is ideal as you can configure each monitoring endpoint to report to one location and visualise/compare/analyse each endpoint within Timebeat’s front end.
One of Timebeat’s unique features is that it is able to synchronise from or monitor multiple sources of UTC in parallel. Using the Multi Source Selection Algorithm (MSSA) Timebeat is able to move past the pitfalls of BMCA and enable a complete end-to-end monitoring solution without the dilution of UTC source.
Timebeat would obtain UTC from the 1PPS output of the GPSDO which would synchronise the microserver and act as a Control Source.
Timebeat would obtain a source of time from a local grandmaster clock via PTP and log offsets whilst in monitor only mode
Timebeat would obtain a source of time from a regional grandmaster clock via PTP and log offsets whilst in monitor only mode
Timebeat would obtain a source of time from a boundary clock via PTP and log offsets whilst in monitor only mode
By configuring Timebeat to operate in MSSA mode, each UTC source delivered via PTP is able to be viewed in the front end. Utilising this method allows us to break up the BMCA solution inputs into their unique sources allowing us to make true comparisons and to validate all sources of UTC in the potential chain of error.
(Control source of UTC)
(local grandmaster clock PTP sync offset to the above)
This type of analysis Is only possible due to Timebeat’s Multi-Source Selection Algorithm and real-time monitoring platform, the flexibility to not only compare sources of UTC but perform calculations based on the offsets observed to truly understand error chains from UTC start to finish. Timebeat to provides an effective UTC Verification system that can be in place 24/7, is easily replicated, and is extremely cost-effective.
In our next post, we will be sharing the results of this setup and some of the surprises we found along the way......
If you can't wait that long then get in touch or check out Timebeat yourself at https://timebeat.app
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