Ensuring Live Streaming Achieves Broadcast Grade

Broadcast service providers delivering live production, contribution, playout and transmission services have observed the continuous and accelerating movement towards OTT services.


This article is part of 'The Big Guide To OTT - The Book'

For years they have been providing live streams to the OVPs (Online Video Providers) of their broadcaster customers, who have then delivered Direct to Consumer via various encoding, packaging, origin, CDN, IXP and ISP platforms.

As the mix of general content delivery continues to shift towards D2C/OTT, and as audience expectations increase for broadcast-grade live video delivery on D2C services, a problem has more clearly emerged – there is one (very high) standard of content production and delivery on existing broadcast transmission networks and onwards to the consumer through various, Satellite, IPTV and Cable TV platforms, and there is another (lower, yet oxymoronically with the potential to be much higher) standard of content delivery on OTT networks. This is bothering leading broadcaster service providers.

To them, the fact that the very high quality, low latency video they prepare and distribute can be damaged and destroyed during OTT delivery is a disservice to their work and to their broadcaster customer’s brand reputation. To them, this type of problem should not, and in fact, must not, exist.

Customer experience of live video is something that keeps broadcasters awake at night. Anyone who has ever stood in a Playout Master Control Room knows that it feels like the emergency room in a hospital or a network operations center in a Telco. The state of readiness is palpitating. The Broadcaster Service Providers who provide the networking and playout services to the industry and make their living from ensuring that live video gets through flawlessly hour after hour feel exactly the same. Live means live, video quality must be excellent, reliability is essential. No discussion.

So what happens when a live stream is handed off perfectly in the figurative video delivery relay race from camera to consumer, and the final leg of the race is full of stumbles, slow-downs, dropped “batons” and a jittery finish to cross the line? Is the company that made such a perfect start to the race happy about the end result? Do they wish they could have finished it themselves?

Enter stage left the next generation of broadcast-grade streaming providers.

Fully equipped with all the skills, instincts, and desires to ensure live video reaches the consumer in the same high standard as it has always reached the consumer, these industry specialists are turning their attention to fix what they see as a growing problem that is eminently fixable. It is also fast becoming their problem to fix, and their revenue to earn.

These trusted partners to broadcasters for many decades have multiple intensifying reasons to act now, summarized simply as 4K+, 5G, FTTH (Fiber To The Home), and D2C. These acronyms spell out why broadcaster service providers should be at the heart of live video delivery for broadcaster D2C services.

4K+ (meaning the ensemble of 4K, UHD, HDR, 8K and future immersive viewing experiences) is coming at us fast. 4K+ will soon become the new normal.  Connected TVs that can handle these formats are being purchased as the new standard, the content (particularly sports and documentaries) is being produced in these formats, the leading content brands are offering it, and the streamers are pushing it. The bitrates for streaming video will at least double from today’s SD/HD norms. Legacy video networks will not keep pace, while Broadband networks are being expanded to handle many 4K+ streams into a single home. OTT will be the home of 4K+ which is a big reason why it will become the new norm for most of the population.

5G will make mobile content consumption easier and better. Mobile devices are already evolving to allow “flip-open bigger-screen” experiences. 5G implementation may even move faster than some fixed broadband networks to offer faster download and streaming speeds. This will simply amplify the interest in OTT services and consumers will become ever more familiar with these apps. D2C service providers know that mobile has typically been for content snacking, while the big screen is for consumption of long-form content and group viewing occasions, but so many of us snack a lot that the volumes on mobile are already significant. 5G and better mobile devices just make this easier, driving the streaming habit forwards.

FTTH is the subject of enormous multi-billion-dollar investments to underpin digital economies everywhere. The 2020s will see most developed nations become FTTH enabled for the majority of their populations, with standard speeds of 1 Gbps expected to most people’s homes. Receiving high quality streams will be easy for those homes (with the important caveat that the CDNs and Telco Core Networks must be able to handle it). That doesn’t mean sustained bitrate to the home will be easy for the ever-higher 4K+ bitrates, but the networks will be beefy enough most of the time. As history has demonstrated, once the technology is there and works well it will be used by consumers (3D did not work well, plus it needs high bandwidth, hence the lack of uptake so far; Broadband and internet-based services on the other hand have grown and grown). In addition, developing countries are improving their network infrastructure and data plans to make broadband services more accessible and affordable. We can expect the additional and affordable bandwidth to be consumed, creating more momentum for D2C service uptake.

And then there is the whole D2C trend. Major broadcasters all over the world are doubling down on their D2C strategies. It is clearly essential for their future. New content production is being targeted at OTT services, audiences are embracing OTT faster than before, and all the above technology is making it the more natural choice for the optimal content consumption experience. On top of that, cord-cutting on traditional Pay-TV services continues as people manage their monthly budgets, leading to the forecast that AVOD services (ad-supported) will very soon surpass SVOD services (subscription-supported) in subscriber volumes, and broadcaster D2C growth for live, linear and VOD is part of that advertising-supported or license-supported picture.

At the moment a peak audience on a mature and successful D2C service – like BBC iPlayer, RAI Play or DAZN – is approximately 10-15% of TV viewing peak. In the next 10 years we may reach 60-80% of a national population at peak on a D2C service, accompanied by much higher bitrates. A lot more video streaming capacity will be required, and quality of delivery will be of paramount importance.

New Opportunities

As specialist broadcast service providers and network operators look at the fast growing requirement for at-scale broadcast-grade streaming video, it is a big opportunity for them to address.

The last 10 years have been mostly about VOD and binge-watching, live that is “good enough” mostly on smaller-screen mobile devices, and a side-business of broadcaster D2C or “TV Everywhere” that is soon set to become the main business. The next 10 years are a big opportunity for the broadcast industry service providers to become big streaming players.

Already these service providers provide broadcast-grade contribution and transmission services to their broadcaster customers. Now they want to add streaming services to their portfolio. And why not? CDN services and solutions exist that they can utilise in new and economically scalable ways compared to the traditional public CDN resell model. ISPs could benefit from specialist partners that aggregate and manage the big streamers who represent such a high percentage of total internet bandwidth consumption. And consumers are moving rapidly to streaming as the preferred platform. So, broadcasters need to ensure their services are of the best quality. Which always means “broadcast-grade” because what else defines “best quality”?

Broadcast service providers that specialise in live video delivery know that they have the operational capability to deliver broadcast-grade services. They need to wrap their arms around the CDN platforms, the ISP relationships, and the player and client analytics, to take as much control as they possibly can of the end-to-end video delivery chain. With this control they can streamline and optimise delivery efficiency, and proactively manage quality. Exactly what the broadcasters require in order to satisfy their quality-expectant audiences and monetize their content.

Looking at the full value chain, already the broadcaster service providers know how to deliver low-latency and high quality. Their first rule is that the end-to-end chain must be set up for success. Upconverting a stream part way through the chain is not a good idea. Progressive content is a must, not interlaced. While you can convert interlaced to progressive, it is best to capture content in progressive. Second, it is best to have dedicated fibre connectivity from point of capture to point of origination. Internet protocols like SRT, Zixi and RIST are helpful for lower budget productions, but when live must mean live these protocols add too many seconds to end to end latency. What we first want is point-to-point fibre transmission with intra-frame encoding like J2K/J2XS for lowest delay and highest quality.

At this point broadcast-grade encoding is necessary to produce consistently high quality and low latency outputs. Then, for high bitrate streaming to bigger screens, low-latency HLS/DASH/CMAF are best – they achieve highest quality at lowest latency. CDN-based delivery of these streams to the receiving Players is required to handle the chunked video fragments to the consumer. This is the dominant model for streaming today and into the future because it sustains the highest quality, which we need on our larger screens and for enjoyable viewing experiences.

When very low latency is required (<1 second), but lower video quality is acceptable, WebRTC (Web Real-Time Communication) is a good choice.  This protocol was developed for video conferencing on browsers and is not compatible with CDN-based delivery. WebRTC can handle all levels of resolution, and it is very fast. But it is not based on video fragments, meaning that a very low level of signal disruption due to network problems (like congestion) can cause a problem with the quality. When consumers request a stream they are directed to the closest WebRTC servers and then receive CBR streams to their devices. If the quality of the connection degrades, the servers will switch to lower bitrate CBR streams. With these two primary content delivery choices, because the internet is not a perfectly consistent system and our viewing enjoyment is generally more important than a few seconds of latency, OTT video uses the chunk-based CDN/Player approach.

Figure 1 – The E2E video delivery chain, encompassing traditional networks and CDNs.

Figure 1 – The E2E video delivery chain, encompassing traditional networks and CDNs.

Once encoded and packaged the streams are pushed out into the distribution networks. The first rule is that for best performance you cannot use an unmanaged IP network like the internet. You must have a managed network. And managed doesn’t mean hundreds or thousands of D2C broadcasters running in a multi-tenant environment where capacity is difficult or impossible to manage. So what does managed mean? Managed means that individual streams are clearly visible to the streaming operator and are proactively managed to broadcast-grade SLAs during live events. Managed means that the fibre connections and hops in the chain from encoder to ISP are under the tight control of an E2E network operator. Managed means that Edge nodes are under the control of the broadcaster service provider so that traffic can be handled, and capacity can be deployed and upgraded rapidly to support D2C service growth.

The CDN component is a major component in this chain. Rather than hand-off to multi-tenant, multi-purpose public CDNs on a pay-as-you-go basis, the leading broadcaster service providers are looking to create purpose-designed video delivery networks. These video delivery networks will be dedicated to live video delivery first, with VOD (or rather catch-up TV which is more relevant for live video) as a natural secondary use case. As we know, live sports and live shows are the big drivers of the largest audiences, and catch-up follows for a short period afterwards. VOD rumbles on all the time but doesn’t drive the biggest peaks of viewing. Plus, from a network management perspective and service management perspective, VOD is easy and Live is hard, simply because of peak capacity consumption and what this means for video delivery quality in a congested and dynamic network environment. This is the basic reason why broadcast service providers offering purpose-built live video streaming services can best solve for 4K+ prime-time live video delivery. They know best what is required to get the video through the pipe.

The ISP relationship is quickly becoming a much more strategic relationship for content providers and their service providers. ISPs are fundamental to the delivery of high-quality video. Edge caches need to be as close as possible to the consumer and the network topology must be designed carefully for live event surges that appear in different geographies (the classic situation is the local sports derby when audiences are more densely populated in particular locations). These situations require ISP collaboration. Ideally the Edge caches are deployed deep inside the ISP networks, not at peering points. Network routing tables should be configured for the expected traffic and should be dynamically adjustable during live events according to the audience behaviour. This becomes even more important as video resolutions increase and the video consumes more bandwidth. The vision is for the broadcaster service provider to become a live video hyper-scaler, representing the collective interests of the small number of broadcasters who are big bandwidth consumers for the ISPs. This approach could also bring benefits to the ISPs who can consolidate operations, reduce core network capacity usage, and optimise their network design to handle 4K+ OTT video.

Broadcast-grade also means having SLAs that provide high-levels of video delivery performance and service availability. This results in broadcaster service providers having 24x7 operational teams with experts on call and swift escalation processes. It also means having resiliency and redundancy built into the network design, so that peak traffic can be managed even if there are significant network outages. Fiber cuts and maintenance outages are notoriously awkward and unavoidable, so systems must cater for these types of unexpected outages, rerouting traffic with no notice. Applying the same design and operational approaches to streaming is essential in order to reach broadcast-grade.

Robert Szabo-Rowe, Senior Vice President of Engineering & Product Management at The Switch states, “For years we have worked with some of the world’s largest live events, ensuring high quality delivery from camera to Headend or Origin Server. Today our customers are ramping up their D2C business and demanding parity of experience between delivery platforms. We believe we can assure quality of delivery to the consumer, leveraging all our experience in video network management for the most demanding audiences”.

In the end, the demand for high bandwidth streaming is coming. It won’t be stopped. The wave already started and is building up, and the tsunami will crash heavily onto the shores of the ISP networks unless there is a change in how we manage the delivery of the video. The Super Bowl is expected to drive about 100 Tbps of bandwidth in the US in 2023. Offering 4K to subscribers on a premier streaming platform in one European country is expected to triple the size of the CDN required to reach about 30 Tbps. These are colossal numbers compared to what we are used to, and they are growing much faster than internet capacity is growing. It needs managing.

Broadcaster service providers who know how to manage live events and live video can respond to this challenge, adopting new technology models that offer a win-win-win for themselves, the broadcasters, and the ISPs. Ultimately, the consumer benefits as these three major industry players can together ensure that the highest possible video quality appears flawlessly on our screens.

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