IPMX promises a ‘plug and play’ out-of-the-box experience, but with uncompressed SMPTE ST 2110 video and audio underneath. Given many tier 1 broadcasters have invested months or years implementing ST 2110. So how can IPMX deliver on its promise to the Pro-AV market?
Andrew Starks from Macnica presents this talk explaining how NMOS will fit into IPMX. Key to enabling a minimal config environment is the added mandatory specifications and standards within IPMX. For instance, while you can build an ST 2110 system without NMOS, that’s not an option for IPMX. The focus is on consistency and interoperability. Optional parts of IPMX cover HDCP carriage, USB, RS232 and IPV6. Many of the things often used within Pro-AV but may not be appropriate for low-cost, small use-cases.
Andrew gives an overview of IS-04 and IS-05 which allow for discovery and control of devices. He then looks at EDID and USB carriage and finishes by discussing why AMWA is choosing to use open specifications rather than creating standards.
The Broadcast Knowledge has documented over 100 videos and webinars on SMPTE ST 2110. It’s a great suite of standards but it’s not always simple to implement. For smaller systems, many of the complications and nuances don’t occur so a lot of the deeper dives into ST 2110 and its associated specifications such as NMOS from AMWA focus on the work done in large systems in tier-1 broadcasters such as the BBC, tpc and FIS Skiing for SVT.
ProAV, the professional end of the AV market, is a different market. Very few companies have a large AV department if one at all. So the ProAV market needs technologies which are much more ‘plug and play’ particularly those in the events side of the market. To date, the ProAV market has been successful in adopting IP technology with quick deployments by using heavily proprietary solutions like ZeeVee, SDVoE and NDI to name a few. These achieve interoperability by having the same software or hardware in each and every implementation.
IPMX aims to change this by bringing together a mix of standards and open specifications: SMPTE ST 2110, NMOS specs and AES. Any individual or company can gain access and develop a service or product to meet them.
Andreas gives a brief history of IP to date outlining how AES67, ST 2110, ST 2059 and the IS specifications, his point being that the work is not yet done. ProAV has needs beyond, though complementary to, those of broadcast.
AES67 is already the answer to a previous interoperability challenge, explains Andreas, as the world of audio over IP was once a purely federated world of proprietary standards which had no, or limited, interoperability. AES67 defined a way to allow these standards to interoperate and has now become the main way audio is moved in SMPTE 2110 under ST 2110-30 (2110-31 allows for AES3). Andreas explains the basics of 2110, AES, as well as the NMOS specifications. He then shows how they fit together in a layered design.
Andreas brings the talk to a close looking at some of the extensions that are needed, he highlights the ability to be more flexible with the quality-bandwidth-latency trade-off. Some ProAV applications require pixel perfection, but some are dictated by lower bandwidth. The current ecosystem, if you include ST 2110-22’s ability to carry JPEG-XS instead of uncompressed video allows only very coarse control of this. HDMI, naturally, is of great importance for ProAV with so many HDMI interfaces in play but also the wide variety of resolutions and framerates that are found outside of broadcast. Work is ongoing to enable HDCP to be carried, suitably encrypted, in these systems. Finally, there is a plan to specify a way to reduce the highly strict PTP requirements.
Once you’ve implemented SMPTE ST 2110‘s suite of standards on your network, you’ve still got all your work ahead of you in order to implement large-scale workflows. How are you doing to discover new devices? How will you make or change connections between devices? How will you associate audios to the video? Creating a functioning system requires an whole ecosystem of control protocols and information exchange which is exactly what AMWA, the Advanced Media Workflow Association has been working on for many years now.
Jed Deame from Nextera introduces the main specifications that have been developed to work hand-in-hand with uncompressed workflows. All prefixed with IS- which stands for ‘Interface Specificaion’, they are IS-04, IS-05, IS-08, IS-09 and IS-10. Between them they allow you to discover new devices, create connections between then, manage the association of audio with video as well as manage system-wide information. Each of these, Jed goes through in turn. The only relevant ones which are skipped are IS-06 which allows devices to communicate northbound to an SDN controller and IS-07 which manages GPI and tally information.
Jed sets the scene by describing an example ST-2110 setup with devices able to join a network, register their presence and be quickly involved in routing events. He then looks at the first specification in today’s talk, NMOS IS-04. IS-04’s job is to provide an API for nodes (cameras, monitors etc.) to use when they start up to talk to a central registry and lodge some details for further communication. The registry contains a GUID for every resource which covers nodes, devices, sources, flows, senders and receivers. IS-04 also provides a query API for controllers (for instance a control panel).
While IS-04 started off very basic, as it’s moved to version 1.4, it’s added HTTPS transport, paged queries and support for connection management with IS-05 and IS-06. IS-04 is a foundational part of the system allowing each element to have an identity, track when entities are changes and update clients accordingly.
IS-05 manages connections between senders and receivers allowing changes to be immediate or set for the future. It allows, for example, querying of a sender to get the multicast settings and provides for sending that to a receiver. Naturally, when a change has been made, it will update the IS-04 registry.
IS-08 helps manage the complexity which is wrought by allowing all audios to flow separately from the video. Whilst this is a boon for flexibility and reduces much unnecessary processing (in extracting and recombining audio) it also adds a burden of tracking which audios should be used where. IS-08 is the answer from AMWA on how to manage this complexity. This can be used in association with BCP-002 (Best Current Practice) which allows for essences in the IS-04 registry to be tagged showing how they were grouped when they were created.
Jed looks next at IS-09 which he explains provides a way for global facts of the system to be distributed to all devices. Examples of this would be whether HTTPS is in use in the facility, syslog servers, the registration server address and NMOS versions supported.
Security is the topic of the last part of talk. As we’ve seen, IS-04 already allows for encrypted API traffic, and this is mandated in the EBU’s TR-1001. However BCP 003 and IS-10 have also been created to improve this further. IS-10 deals with authorisation to make sure that only intended controllers, senders and receivers are allowed access to the system. And it’s the difference between encryption (confidentiality) and authorisation which Jed looks at next.
It’s no accident that security implementations in AMWA specifications shares a lot in common with widely deployed security practices already in use elsewhere. In fact, in security, if you can at all avoid developing your own system, you should avoid it. In use here is the PKI system and TLS encryption we use on every secure website. Jed steppes through how this works and the importance of the cipher suite which lives under TLS.
The final part of this talk is a case study where a customer required encrypted control, an authorisation server, 4K video over 1GbE, essence encryption, unified routing interface and KVM capabilities. Jed explains how this can all be achieved with the existing specifications or an extension non top of them. Extending the encryption methods for the API to essences allowed them to meet the encryption requirements and adding some other calls on top of the existing NMOS provided a unified routing interface which allowed setting modes on equipment.
As you walk around any exhibitions there seems to be a myriad of ‘benefits’ of IP working, many of which don’t resonate for particular use cases. Only the most extraordinary businesses need all of the benefits, so in this talk, Imagine Communication’s John Mailhot discusses how IP helps sports venues.
John sets the scene by separating out the function of OB trucks and the ‘inside production’ facilities which have a whole host of non-TV production to do including driving scoreboards, displays inside the venue, replays and importantly has to deal with over 250 events a year, not all of which will have an OB truck.
We see that the scale that IP can work at is a great benefit as many signals can fit down one fibre and 2022-7 seamless switching can easily provide full redundancy for every fibre and SFP. This is a level of redundancy which is simply not seen in SDI systems. With stadia being very large, necessitating cable runs of over 500m, the fact that IP needs fewer cables overall is a great benefit.
John shows an example of an Arista switch only 7U in height which provides 144x 100G ports meaning it could support over 4000 inputs and 4000 outputs. Such density is unprecedented and for OB trucks can be a dealbreaker. For sports venues, this can also be a big motivator but also allow more flexibility in distributing the solution rather than relying on a massive central interconnect with a 1100×1100 SDI router in a central CTA.
TV is nothing without audio and the benefits to audio in 2110 are non trivial since with the audio being split off from the video, we are no longer limited to dealing with just 16 channels per video and de-embedding from a video frame any time we want to touch it.
Timing is an interesting benefit. I say this because, whilst PTP can end up being quite complex compared to black and burst, it has some big benefits. First off, it can live in the same cables as your data where as black and burst requires a whole separate cable infrastructure. PTP also allows you to timestamp all essences which helps with lip-sync throughout your workflow.
John leads us through some examples of how this works for different areas finishing by summing up the relevant benefits such as scalability, multi-format, space efficient, and timing amongst others.
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