ST 2110

Where can SMPTE 2110 and NDI co-exist?

Posted on by Russell Trafford-Jones

Our final look back at the most viewed articles of 2020 is a very prescient topic, that of live IP production. As we all know, this has very much come into focus during the pandemic. Those that already had an IP infrastructure found managing it remotely easier than those that needed to get in and move SDI cables when they needed to provision new video links. Moreover putting together live remote workflows is all the easier with video IP and traditionally the decision on whether to use SMPTE 2110 has been a case of whether you need to be in the cloud or not.

This article and video brought together Will Waters, an NDI expert from VizRT, Marc Risby from UK SI Boxer and Willem Vermost who was with the EBU. The conversation, pre-pandemic, focused on how to choose the video-over-IP technology which was best for you and really tried to find the ways in which broadcasters could benefit from both at the same time.

The Broadcast Knowledge Editor, Russell Trafford-Jones also moderated a SMPTE Webcast with VizRT going into the detail of NDI and how it can be deployed in the cloud.

Another important advance in 2020 was AWS’s release of CDI which is an implementation of SMPTE 2110 with enough proprietary adaptations to make it work within AWS. You can hear more about it in this video with David Griggs.

Click here to watch ‘Where can SMPTE 2110 and NDI co-exist?’

Video: ST-2110 – Measuring and Testing the Data, Control and Timing Planes

Posted on by Russell Trafford-Jones

An informal chat touching on the newest work around SMPTE ST-2110 standards and related specifications in today’s video. The industry’s leading projects are now tracking the best practices in IT as much as the latest technology in IP because simply getting video working over the network isn’t enough. Broadcasters demand solutions which are secure from the ground up, easy to deploy and have nuanced options for deployment.

Andy Rayner from Nevion talks to Prin Boon from Phabrix to understand the latest trends. Between then, Andy and Prin account for a lot of activity in standards work within standards and industry bodies such as SMPTE, VSF and JT-NM to name a but a few, so whom better to hear from regarding the latest thinking and ongoing work.

Andy starts by outlining the context of SMPTE’s ST-2110 suite of standards which covers not only the standards within 2110, but also the NMOS specifications from AMWA as well as the timing standards (SMPTE 2059 and IEEE 1588). Prin and Andy both agree that the initial benefit of moving to IT networking was benefiting from the massive network switches which now delivering much higher switching density than SDI ever could or would, now the work of 2110 projects is also tracking IT, rather than simply IP. By benefiting from the best practices of the IT industry as a whole, the broadcast industry is getting a much better product. Andy makes the point that broadcast-uses have very much pushed fabric manufacturers to implement PTP and other network technologies in a much more mature and scalable way than was imagined before.

Link to video

The focus of conversation now moves to the data, control and timing plane. The data plane contains the media essences and all of the ST 21110 standards. Control is about the AMWA/NMOS specs such as the IS-0X specs as well as the security-focused BCP-003 and JT-NM TR-1001. Timing is about PTP and associated guidelines.

Prin explains that in-service test and measurement is there to give a feeling for the health of a system; how close to the edge is the system? This is about early alerting of engineering specialists and then enable deep faultfinding with hand-held 2110 analysers. Phabrix, owned by Leader, are one of a number of companies who are creating monitoring and measurement tools. In doing this Willem Vermost observed that little of the vendor data was aligned so couldn’t be compared. This has directly led to work between many vendors and broadcasters to standardise the reported measurement data in terms of how it’s measured and how it is named and is being standardised under 2110-25. This will cover latency, video timing, margin and RTP offset.

More new work discussed by the duo includes the recommended practice, RP 2059-15 which is related to the the ST 2059 standards which apply PTP to media streams. As PTP, also known as IEEE 1588 has been updated to version 2.1 as part of the 2019 update, this RP creates a unified framework to expose PTP data in a structured manner and relies on RFC 8575 which, itself, relies on the YANG data modeling language.

We also hear about work to ensure that NMOS can fully deal with SMPTE 2022-7 flows in all the cases where a receiver is expecting a single or dual feed. IS-08 corner cases have been addressed and an all-encompassing model to develop against has been created as a reference.

Pleasingly, as this video was released in December, we are treated to a live performance of a festive song on piano and trombone. Whilst this doesn’t progress the 2110 narrative, it is welcomed as a great excuse to have a mine pie.

Watch now!
Speakers

Andy Rayner Andy Rayner
Chief Technologist,
Nevion
Prinyar Boon Prinyar Boon
Product Manager,
PHABRIX

Video: Proper Network Designs and Considerations for SMPTE ST-2110

Posted on by Russell Trafford-Jones

Networks from SMPTE ST 2110 systems can be fairly simple, but the simplicity achieved hides a whole heap of careful considerations. By asking the right questions at the outset, a flexible, scalable network can be built with relative ease.

“No two networks are the same” cautions Robert Welch from Arista as he introduces the questions he asks at the beginning of the designs for a network to carry professional media such as uncompressed audio and video. His thinking focusses on the network interfaces (NICs) of the devices: How many are there? Which receive PTP? Which are for management and how do you want out-of-band/ILO access managed? All of these answers then feed into the workflows that are needed influencing how the rest of the network is created. The philosophy is to work backwards from the end-nodes that receive the network traffic.

Robert then shows how these answers influence the different networks at play. For resilience, it’s common to have two separate networks at work sending the same media to each end node. Each node then uses ST 2022-7 to find the packets it needs from both networks. This isn’t always possible as there are some devices which only have one interface or simply don’t have -7 support. Sometimes equipment has two management interfaces, so that can feed into the network design.

PTP is an essential service for professional media networks, so Robert discusses some aspects of implementation. When you have two networks delivering the same media simultaneously, they will both need PTP. For resilience, a network should operate with at least two Grand Masters – and usually, two is the best number. Ideally, your two media networks will have no connection between them except for PTP whereby the amber network can benefit from the PTP from the blue network’s grandmaster. Robert explains how to make this link a pure PTP-only link, stopping it from leaking other information between networks.

Multicast is a vital technology for 2110 media production, so Robert looks at its incarnation at both layer 2 and layer 3. With layer 2, multicast is handled using multicast MAC addresses. It works well with snooping and a querier except when it comes to scaling up to a large network or when using a number of switches. Robert explains that this because all multicast traffic needs to be sent through the rendez-vous point. If you would like more detail on this, check out Arista’s Gerard Phillips’ talk on network architecture.

Looking at JT-NM TR-1001, the guidelines outlining the best practices for deploying 2110 and associated technologies, Robert explains that multicast routing at layer 3 works much increases stability, enables resiliency and scalability. He also takes a close look at the difference between ‘all source’ multicasting supported by IGMP version 2 and the ability to filter for only specific sources using IGMP version 3.

Finishing off, Robert talks about the difficulties in scaling PTP since all the replies/requests go into the same multicast group which means that as the network scales, so does the traffic on that multicast group. This can be a problem for lower-end gear which needs to process and reject a lot of traffic.

Watch now!
Speaker

Robert Welch Robert Welch
Technical Solutions Lead
Arista Networks

Video: NMOS Technology: A User’s Perspective

Posted on by Russell Trafford-Jones

Bringing you discovery, registration, control, audio remapping, security and more, the open NMOS specifications from AMWA make using SMPTE’s ST 2110 practical. Most importantly, it makes using 2110 open meaning that different equipment can co-exist in the same ecosystem without being many different drivers being written to translate between each vendor.

Led by Wes Simpson this video talks about implementing NMOS from the perspective of a user, not a vendor with Willem Vermost> from Belgium’s public broadcaster, VRT. One drawback of IP-based solutions, they say early on, is that there are so many options on how to deploy. This potential choice paralysis goes hand in hand with trying to adapt to the new possibilities which come with the technologies. For instance, identifies Willem, says engineers need to adapt their thinking just to design differently knowing that, now, multiple signals can now flow in both directions down a cable. It’s not like SDI’s point to point, unidirectional nature.

Any large plant can get busy with thousands of signals. The question is how to control this massive number of streams; not forgetting that in 2110, an SDI video stream is split up into at least 4 streams. To help put this into perspective, Willem looks back to the original telephone exchange and considers the different workflows there, They work, certainly, but having people present plugging in each individual call doesn’t scale well. In our IP world, we want to get beyond the need to ‘type in an address’ as we want to capture the ease at which cameras are connected

The telephone exchanges worked well but in the early days, there were many exchange manufacturers which, when calling from Berlin to New York all had to work. Willem suggests this is why telecoms acted upon what the broadcast industry is now learning. The last point in this analogy is the need to stop your links between exchanges from becoming over-subscribed. This task is one which NMOS can also be used to deal with, using IS-05.

NMOS is fully available on GitHub and whilst you can take that software and modify it to your needs, Willem says it’s important to maintain interoperability between vendor implementations which is why the JT-NM Tested programme exists to ensure that it’s easy to buy on the market solutions which say they support NMOS and when they do, that it works. Getting an NMOS test system is easy with open projects from Siny and NVIDIA which are ready for deployment.

Willem ends his talk by saying that ST 2110 is easier now than it was, including a recent experience when the en/decoder worked ‘out of the box’. He then answers the question “How do I start out?” Saying you should try something small first, perhaps even an island project. Once you have done that, gained the experience and the concepts, you can take it from there.

Watch now!
Speakers

Willem Vermost Willem Vermost
Design & Engineering Manager,
VRT
Wes Simpson Wes Simpson
Owner, LearnIPVideo.com