Video: When Low Latency Matters, and When it Doesn't
Learn more about latency at Streaming Media's next event.
Watch the complete video of this panel from Streaming Media West, DT103. The Road to Scalable, Real-Time Live Streaming, in the Streaming Media Conference Video Portal.
Read the complete transcript of this clip:
Tim Dougherty: I get on the phone with folks who want to build the next gigantic, big, evil streaming corporation dot-com, and they don't always know what they need. One of the first things I ask when they saw low latency--I seriously ask them--"Why? Are you sure you need low latency? What is latency to you?"
Because ultra-low latency is cutting-edge technology. This is something that's continuing to evolve. There are more codecs and there's more about this story that's going to be told, but right now it's a challenging thing to do. We can do it, but if you can do it with Apple HLS and a more conventional, more stable workflow, I strongly suggest doing that.
But in the case of auctions, eSports, gambling, medical applications, sports, it matters. Nobody wants to see on Twitter what happened 30 seconds ago. You want to be sync'd up.
When there's a touchdown and one of your friends has got it on Facebook and you see comments about it, you want to see what’s happening right now, not 30 seconds ago.
I think about auctions. A few years ago I got a call from a couple of cowboys in Alberta, Canada, and you know, we all work in the tech business for the most part, and we're always thinking about these really cool companies we work with. I was working with such and such broadcaster, and we love to talk about these really cool workflows. These were a couple cowboys that I pictured smelled like cows, and they had that vibe, you know? And they're kind of like "Yeah, we want to do a cattle auction.” And I ended up having this really cool conversation.
They need low latency. They have a cattle auction that's live. They're selling cattle live. That's a great, albeit a very simple, probably a very small-scale use case, but it applies. There are a lot of opportunities for low latency to make sense. Social media, eCommerce, government. I won't belabor this too much. The game shows, the HQs, the really cool interactive stuff happening now. Just a little bit of background.
There are a few ways that we can categorize this. Number one, you've got common HTTP latencies today. I love what I do. I really enjoy working with the Wowza Streaming Engine software, and sometimes people don't understand that HTTP latency isn't necessarily our fault. HTTP was designed for graphics and images. Those older guys like me that have been around, we remember how slow things happened over dial-up, and remember when the internet and the browsers, there was Netscape and there was those older technologies, and they could barely render an image, right?
That's the same protocol except somebody--Apple--figured it out how to do it over HTTP. So there is an inherent latency because you're watching a chunk of video right after a chunk of video back to back to back to back. It's super stable, but it does create a latency problem.
So you get 45 seconds out of the box with standard, reliable, good, old-fashioned, Apple HLS or MPEG-DASH. There's ways to do it where you can squeeze it down. OTTs have it inside an 18-second range. This might be something you would get from a cable operator. Maybe you have a set-top box that's using a more aggressive protocol.
We did this when we were starting to get into the low-latency business. We had a whole bunch of Wowza employees figure out the latency on their cable box at home. We had a way of comparing it to OTA versus what they were seeing on Spectrum, on DirecTV, on Comcast, on whatever, and it's about a five-second latency to live. So even watching satellite television, cable television, it's about five seconds.
Latency isn't something new, and then you move over into the lower-latency category where you're dealing with user-generated content, live streams, game streaming, eSports. So the farther you go to the right, the more challenging, the more cutting-edge, the more difficult it is for the networks, the more difficult it is for the clients, but you're getting into more real-time protocol. You guys probably use Zoom, GoToMeeting, BlueJeans, those type of clients. Those are cutting edge. That is near-realtime communication.
Low latency video streaming is on everyone's mind, but figuring out the latency your project needs—as well as how to get it—can be a slow process. Let this article be your guide.
Wowza Media Systems Senior Solutions Engineer Tim Dougherty surveys the recent and current state of streaming latency in this clip from his presentation at Streaming Media West 2018.
RealEyes' David Hassoun discusses what low latency is and what it isn't, and sets reasonable expectations for the current content delivery climate.
Wowza Senior Product Manager Jamie Sherry discusses key latency considerations and ways to address them at every stage in the content creation and delivery workflow.
Wowza's Mike Talvensaari confronts the myth that low latency for large-scale streaming is always worth the expense, and discusses various applications and use cases along a continuum of latency requirements for effective delivery.
Ooyala's Paula Minardi and Level 3's Jon Alexander discuss the key issues facing live streaming and VOD providers regarding latency times, buffering, and meeting evolving viewer expectations.