As more viewers around the globe stream more live video more often, programmers are increasingly using multiple content delivery networks (CDNs) to ensure the high-quality video consumers want and—in a testament to advances in the field—have come to expect.
Splitting business among two or more CDNs, particularly for live sporting events, can be an insurance policy in case one falters, or a nod to the fact that some CDNs cover certain geographic areas better than others.
“For a sizable event, we use at least three [CDNs],” said Joe Inzerillo, executive vice president and CTO of Walt Disney’s BAMTech Media. Operating under Disney streaming services, BAMTech provides the backend platform for ESPN+ streaming and streaming services for other Disney products and external clients. “We almost never go under two [and] have gone as high as five or six.”
The goal is to limit latency, or time lost to buffering and unplanned outages that can be caused by heavy traffic. “Think of it like a nightclub with rooms and you’re having a good time. Then a different DJ comes on and the floor gets crowded and then you aren’t having such a good time,” Inzerillo said.
Eric Black, senior vice president and CTO of NBC Sports Digital and Playmaker Media, said the multiple-CDN strategy was initially seen as a way save money by pitting networks against each other to get the lowest transfer cost. Now it’s about ensuring quality.
“It’s a hedge,” said Black, who orchestrated three of the biggest digital events of 2018—Super Bowl LII, the Winter Olympics and the FIFA World Cup. He said he tends to use a primary CDN for the lion’s share of traffic, with several others providing backup. He knows programmers that use as many as seven.
“Adding [that many] more is not necessarily better,” he said, given the intricacies of prestream setup and testing ahead of large events. “It’s not worse, but more prep. You have to think, are you adding value?”
With more than 13 billion connected devices worldwide, video streaming accounted for 75% of all internet traffic in 2017—a figure expected to jump to 82% by 2020. And livestreaming, about 13% of the total and growing, is no longer a niche but a staple. Sports draws the most live viewers.
CDNs are networks of servers that deliver web content to users based on the geographic locations of users and servers and the origin of the websites. The closer a server and viewer are, the better the stream. The biggest CDNs, including Akamai and Limelight, have their own proprietary networks with servers around the world. It’s a highly competitive industry that recently started to emerge from a broad slump in revenue from media, according to Kagan, a research division of S&P Global Market Intelligence. Kagan anticipated that CDN provider revenue of $1.8 billion in 2017 will rise to an estimated $2.2 billion in 2022 as continued declines in price per gigabyte are offset by increases in overall traffic and a growing number of streams to larger screens like connected TVs.
There are some 50-plus players in the CDN market from pure plays to innovators like Qwilt and Fastly to diversified titans like Amazon, Verizon, Google and Comcast.
For CDNs, sharing the proverbial stage for livestreaming events is a growing reality of their business.
“There is a global audience and a lot of traffic,” said Mike Milligan, senior director and product and solution marketing at Limelight. “We have a private network in more than 80 locations and 35 terabytes of capacity to deliver, but that does not mean we can do that at full scale around the world all the time,” he said, “especially if there are large events in different parts of the world."
Clients use the multi-CDN strategy differently, he said. Some award traffic based on geography, others on a percentage model with perhaps each of three CDNs getting a third. Programmers can also base traffic allocation based on real-time data culled by sophisticated software or human staffers who monitor the multiple delivery networks during a stream and can switch between them.
“They know what your performance is. They can reward you in real time,” said Milligan. “We are okay with that. We are quite happy with that.”
Jon Alexander, senior director of product management for Akamai, also saw the multiple-CDN trend as an opportunity to prove itself by going head-to-head with rivals.
But Alexander urged cautioned. “If you switch traffic aggressively you can cause problems,” he said. “When you get it wrong, you can make things worse.”
The industry’s endgame, constantly challenged by rapid shifts in consumer habits and technology, is ultimately to perfect a livestreaming experience to rival live television. Some think it could even be better.
After all, streaming “has 4k and potential for interactivity,” said Jason Thibeault, executive director of the Streaming Video Alliance, an industry forum based in Fremont, California. “But at least right now can we just bring it up to par, so it’s consistent?”
“You press the power button and the TV just works. You move channels and it just works,” he said. In livestreaming there’s “sometimes a buffer, sometimes a jitter. And you say, ‘That’s not like TV.’”
Inzerillo agreed that, “Doing [livestreaming] okay has gotten easier” but, “it is really hard to do well.”
“The internet does not really want [us] to exist. [It] was never orchestrated for the carrying of video files,” he said. “If you were going to start today and start on a clean sheet of paper, you would not design it the same way.”