RIST solves a problem by transforming unmanaged networks into reliable paths for video contribution. This comes amidst increasing interest in using the public internet to contribute video and audio. This is partly because it is cheaper than dedicated data circuits, partly that the internet is increasingly accessible from many locations making it convenient, but also when feeding cloud-based streaming platforms, the internet is, by definition, part of the signal path.
Packet loss and packet delay are common on the internet and there are only two ways to compensate for them: One is to use Forward Error Correction (FEC) which will permanently increase your bandwidth by up to 25% so that your receiver can calculate which packets were missing and re-insert them. Or your receiver can ask for the packets to be sent again.
RIST joins a number of other protocols to use the re-request method of adding resilience to streams which has the benefit of only increasing the bandwidth needed when re-requests are needed.
In this talk, Ciro Noronha from Cobalt Digital, explains that RIST is an attempt to create an interoperable protocol for reliable live streaming – which works with any RTP stream. Protocols like SRT and Zixi are, to one extent or another, proprietary – although it should be noted that SRT is an open source protocol and hence should have a base-level of interoperability. RIST takes interoperability one stage further and is seeking to create a specification, the first of which is TR-06-1 also known as ‘Simple Profile’.
We then see the basics of how the protocol works and how it uses RTCP for singling. Further more RIST’s support for bonding is explored and the impact of packet reordering on stream performance.
The talk finishes with a look to what’s to come, in particular encryption, which is an important area that SRT currently offers over and above reliable transport. Watch now!
OB vans have been notable early adopters of Video over IP, both in the form of SMPTE ST 2110 and ST 2022-6. The reasons are simple, all new vans are ‘green field’ sites, weight and space are at a premium and many need more weekly flexibility than SDI has been giving them.
In this case study, Hartmut Opfermann discusses design considerations for all IP large OB trucks dedicated for sports, music and entertainment production and explores the decisions that have been made for ORF’s new FU22 OB tuck including the drivers behind switching to IP technology and SMPTE ST 2110 for media transport.
Interesting to note is the proportion of SDI Vs IP in new IP installations. BBC Cardiff, for instance, has a minimum quota for IP-enabled endpoints but isn’t assuming it can reach 100%. There are few IP installations which are 100% IP.
In ORF’s truck we also see that, although the truck is fully based on IP technology, SDI-IP gateways have been provided to keep compatibility with existing baseband infrastructure. Keeping all internal processing in the IP domain simplifies cabling, reduces cable weight but, importantly, enables the use of flexible FPGA based processing platforms – functionality thus depends on software and can be changed on fly.
The broadcast control system provides a single point of control over complex infrastructure of the truck and provides a seamless experience for operators who used to work in the SDI domain. However, configuration and troubleshooting of IP systems requires a very different skillset, so training had to be provided to ORF engineering team.
The still-growing NMOS suite of specifications from AMWA defines ways in which your IP network can find and register new devices plugged in to it (e.g. camera, microphone etc.), manage their connections and control them. They fit neatly along side the SMPTE ST 2110 suite of standards which define the way that the essences (video, audio, metadata) are sent over networks intended for professional media.
As such, they are core to a network and as the market for uncompressed media products matures, the attention is on the details such as whether they scale and security.
In this talk, Simon Rankine from BBC R&D starts by explaining the objectives which means looking at the different aspects of security which is split into three; securing data transfer, ensuring data goes to the right place, ensuring only authorised people can act.
TLS, standing for Transport Layer Security, is the same protocol used for secure websites; those which start with https://. It is also referred to by the name of the protocol it replaced, SSL. Given the NMOS APIs are sent over HTTP, TLS is a perfect match for the use case. TLS provides not only the ability to encrypt the connection but also provides the basis for certificate exchange which allows us trust that the data is being sent to the right place. Simon then covers ciphers and TLS versions before talking about certificate management.
This talk was given at the IP Showcase at NAB 2019.
Well ahead of video, audio moved to uncompressed over IP and has been reaping the benefits ever since. With more mature workflows and, as has always been the case, a much higher quantity of feeds than video traditionally has, the solutions have a higher maturity.
Anthony from Ward-Beck Systems talks about the advantages of audio IP and the things which weren’t possible before. In a very accessible talk, you’ll hear as much about soup cans as you will about the more technical aspects, like SDP.
Whilst uncompressed audio over IP started a while ago, it doesn’t mean that it’s not still being developed – in fact it’s the interface with the video world where a lot of the focus is now with SMPTE 2110-30 and -31 determining how audio can flow alongside video and other essences. As has been seen in other talks here on The Broadcast Knowledge there’s a fair bit to know.(Here’s a full list.
To simplify this, Anthony, who is also the Vice Chair of AES Toronto, describes the work the AES is doing to certify equipment as AES 67 ‘compatible’ – and what that would actually mean.
This talk finishes with a walk-through of a real world OB deployment of AES 67 which included the simple touches as using google docs for sharing links as well as more technical techniques such as virtual sound card.
Packed full of easy-to-understand insights which are useful even to those who live for video, this IP Showcase talk is worth a look.
For many building a good network for a 2110 or other media-over-IP standards is new and a bit scary. But if there’s one person who knows how to do it, it’s Arista’s Gerard Phillips who’s here to go through the basics and build up the network needed for a large and scalable network.
Scalability is the heart of this, because life does change – your company grows, technology pushes you from SD to HD to UHD etc. So you need to build scalability in from the beginning. Getting this right comes down to choosing the right hardware and having the right architecture.
Gerard looks at switch architecture and bandwidth both in the switch and of the network cables. He then looks towards ‘hub and spoke’ Vs monolithic switch design. What are the pros and cons to each and which is right for you?
SDN – Software Defined Networking – is also a key ingredient in such a network. This is where the routing decisions of the switch infrastructure is taken out of the switches because they have automatic and blinkered algorithms and takes it to a server which has a complete overview of the whole system. For a broadcaster who deals with critical signal chains – this is usually the best approach to give determinism and safety to the network.
PTP – Precision Time Protocol – provides the foundation of the 2110 standard and is therefore very important to studio installations being used to replace black and burst. What are the best ways to distribute this and how can you deal with redundancy?
These topics and more are all covered at this IP Showcase presentation from IBC 2018.
With all the talk of the SMPTE ST 2110 standards suite, it’s sometimes forgotten that it only deals with content. If you want a working system, you’ll need to do a few more things – find new devices on the network, work out what they can do, control them, guarantee the bandwidth and often deal with metadata that arrives separately like tallies.
This is what the AMWA NMOS specifications do. Peter Brightwell and Thomas Edwards have been heavily involved in creating them and in this video lead us through what each one does and how they are used.
In a continuing series of videos which dig deeper than just saying ‘hooray, IP is great’, we look at the onerous task of actually planning and deploying a whole building’s worth of 2110. From the IPShowcase at IBC 2018, Ultich Voigt from Qvest Media explains how they helped Swiss public broadcaster SRG/SSR to build their new facility – the TPC Sports, News & Technology centre.
Ulrich looks at how functions can be centralised and/or consolidated and whilst he talks of the technology standards in use, the highlight here are the workflows achieved.
Aims of the project
Technical Goals and Standards
How they got experience in using IP ahead of the project
Testing planning & issues rectification
Deciding whether to go ‘Full IP’ and what that means
AMWA’s discovery and registration protocols IS-04 and IS-05 play a big role in making IP systems usable, allowing the system to easily identify new kit when it’s plugged in and understand its capabilities. However, deploying such systems at scale should give anyone pause for thought – how scalable are they? How does the system recover after a network outage? Clearly we wouldn’t want the system to be brought down by the administrative burden.
Rob Porter, from Sony Europe Ltd., has done the research and presents it here at the VSF’s IP Showcase at the 2018 IBC.
Rob gives a brief overview of the two specifications, describing their APIs and the open source nature of them. He then goes on to explain how he emulated this large number of devices and what he found.
Finally, Rob wraps up the session by explaining how he optimised network-loss recovery times and summarises best practices.
An increasing amount of broadcast video is travelling over the public internet which is currently enabled by SRT, Zixi and other protocols. Here, Merrick Ackermans explains the new RIST specification which aims to allow interoperable internet-based video contribution.
Speaking at the IP Showcase at IBC 2018, Merrick covers:
Andy Rayner from Nevion looks at using SMPTE ST 2110 on a Wide Area Network (WAN).
While using ST 2110 is a much discussed topic in the studio or within a building, there are extra difficulties in putting it between buildings, cities and countries with some saying it shouldn’t even be done. Here, Andy examines how you can do it whilst acknowledging the industry still has some decisions to make.