Low-latency streaming has become the go-to standard for delivering real-time content, but what does it actually mean? Is it something your business needs, or is it just a hyped-up buzzword?
Spoiler: Low latency could be incredibly important for your brand, depending on the types of content you produce and deliver.
Ultra-low-latency streaming might not be critical for watching a live music concert, but you can imagine its application for betting on a live event or avoiding spoilers in a sports game because your friend’s streaming service delivers it faster.
Fans and customers demand near-real-time streaming, and it’s up to you to deliver. Below, we’ll walk you through everything you need to know about low latency to stream better content, satisfy your customers, and beat out the competition.
What Is Latency?
Latency refers to the amount of time it takes for data to transfer over a network connection. The camera captures the action, the data is uploaded to the network and delivered to the consumer, and the consumer watches it—the time it takes for that to happen is what we call video streaming latency.
We measure latency in milliseconds (ms), and it’s estimated based on the round-trip time for a packet to travel from the source to the destination and back to the source.
Naturally, sending data over a network takes time, especially when the source and end destination are far apart. However, the ultimate goal is to decrease latency and make the viewing experience as real-time as possible.
That’s easier said than done.
Fortunately, we have a few ways to help you achieve low-latency video streaming, regardless of your content or audience size—more on that soon.
Many people use terms like latency, lag, and buffering interchangeably—yet, these aren’t the same terms and don’t mean the same thing. Here’s a quick overview of the differences:
- Buffering: Buffering is when a device stores data temporarily to deliver it in a continuous flow, resulting in fewer disruptions during playback.
- Lag: Latency measures the time it takes for a data packet to travel, while lag measures the time between an action and a result. For example, you’re experiencing lag when you press a button on a controller and it takes time for the device to respond accordingly.
- Packet loss: Packet loss refers to data lost in the transferring process.
What Causes Latency?
Latency isn’t an unavoidable byproduct of livestreaming. It can be changed and improved. Before we can learn how to improve your latency and achieve low latency streaming (or ultra-low latency), we need to understand the impacting factors.
The following aspects affect your latency:
- Encoding: Your encoder must process, compress, and format the raw video files for delivery and playback.
- Transcoding: Your streaming server must transcode the live video files for playback on different devices, screen sizes, bandwidths, and resolutions.
- Content delivery network (CDN): Your data must be transferred to the appropriate local CDN, where it will then be delivered to the customer.
- Bandwidth: Your bandwidth (and your customer’s bandwidth) impact how long it takes data to travel between the source and destination.
- Physical distance: The further the end destination is from the source, the longer it’ll take to deliver the content. CDNs help alleviate this issue, but it’s always going to take longer to stream something across the world than it would be to stream it to your next-door neighbor.
- Hardware: Old hardware mixed with new software can cause latency issues—and the hardware matters from the source to the server to the end user.
What Is Low Latency?
Low latency lacks an official definition, but most sources agree that it means a glass-to-glass delay of five seconds or less. However, the difference between five seconds, two seconds, and real-time can be extremely important depending on your live-streamed content. That’s why sub-categories of low latency have emerged:
- Ultra-low latency: Tends to be one second or less of glass-to-glass delay.
- Real-time latency: Real-time latency (also called zero-latency live streaming) usually means the same as ultra-low latency—one second or less delay.
Normal latency can range from 30 to 120-second delays, while reduced latency refers to 5 to 18 seconds of delays.
Why Is Low Latency Important?
While all this latency talk might sound like nitty-gritty details, every second counts when it comes to live streaming. Today’s consumers want real-time content, and they want videos they can engage with. Whether commenting on an esports match or interacting with their cycling fitness instructor, they don’t want the experience muddled by lag and delay.
Here are a few reasons low latency is a must-have for modern-day streaming:
- User experience: Imagine attending a live event and watching a play on the big screen, seeing a quarterback get ready to make a throw, and hearing all the fans around you scream, “It’s a fumble!” Latency can hurt the user experience, spoil events, and irritate customers.
- Safety: There’s no room for latency when you need real-time monitoring of search-and-resue missions, drone footage, bodycams, or patient monitoring.
- Engagement: Low latency enables interactivity and engagement with live streams. Participants can communicate in real time via the chat, and hosts can respond immediately rather than after a 30-second delay.
Who Needs Low Latency?
Low latency is the goal for every publisher, but certain industries and use cases consider it non-negotiable. Here are a few examples of streaming use cases where low latency isn’t a nice-to-have—it’s a need-to-have:
Sports
Fans want the ultimate viewing experience when watching sports. Spoilers are an offense, and they’ll take it personally. You need to stream these live events in near real-time to avoid the following:
- Social media comments: 5-30 seconds delay gives your loyal social media friends plenty of time to Tweet about a goal or touchdown before you’ve seen it for yourself.
- App notifications: Sports apps (and even some live streaming apps) will send notifications when a significant event has happened, such as a touchdown, goal, or red card—if these apps deliver the news before the screen does, you’ve got a problem.
- In-person celebrations: Your neighbors or friends might be watching the big game via a television broadcast while you’re consuming it through a live streaming application—if you don’t have a low latency provider, you’ll hear all their “ooohs,” “ahs,” and cheers before you see it on your screen.
Gaming
Esports and online gaming streamers need low latency for engagement and fairness. Betting is a big deal for these sports (as well as in-person sports), and real-time betting gets messy when you’re at a latency disadvantage.
Big-time gaming influencers also need low latency to engage with their audiences. While playing games, they often interact with the chat and viewing participants—if there’s a significant delay, responses could be awkward or irrelevant.
Fitness
Once upon a time, users consumed fitness classes through DVDs—nowadays, they interact live with instructors during the workouts. Instructors engage with the audience and get real-time insights into the participants’ performance.
Whether hosting a live-streamed fitness class through social media or a live-streaming platform, you need low latency to engage with your audience. If you need to give instructions, provide tips, or answer questions, you (and your audience) want the conversations in real time—not with a 30-second delay.
News
News is all about timing, and every second counts. Every second your stream wastes in latency is an opportunity for a competitor to cover the story first, and that’s a golden chance for them to steal your audience for good.
Deliver timely news with all the latest information at low-latency streams to keep the trust and engagement of your audience.
Online Education
Latency isn’t as important when consuming VOD learning courses, but it’s critical for live-streaming learning for high school, college, or extracurricular classes. Teachers and participants need to interact, ask questions, and give answers. Delays can cause confusion, and instructors might start moving on before the high latency gives the class an opportunity to consume and engage.
Social Media
Live streaming on any social media platform (TikTok, Instagram, YouTube, etc.) needs to be in real-time. These are engagement opportunities where influencers and users interact through interactive video and chat. Any sort of latency would hurt the user experience and decrease the quality of the stream.
How Can You Achieve Low Latency Streaming?
You can’t control everything about your latency and the user experience, but you can own a handful of aspects. Everything from the video platform you use to the encoding options you set will impact latency. Here are a few best practices to optimize for low-latency streaming:
1. Encode Your Videos Correctly
Make compromises between quality and performance. You can reduce latency by using the right compression standards without significantly decreasing the quality of the live stream.
Industry-leading video encoders and decoders can compress videos to low bitrates without negatively impacting picture quality. This level of compression makes the data transfer faster, resulting in lower latencies for your audience.
2. Use a Multi-CDN Approach
CDNs reduce latency issues caused by geographic distance. Your server will send content to local CDNs, and the systems will direct traffic to the closest CDN to stream the content. A multi-CDN approach with points of presence (POPs) around the world will ensure smooth delivery and playback to a global audience.
3. Choose the Best Transport Protocols
HTTP-based protocols (like Apple HTTP Live Streaming (HLS) and MPEG-DASH) deliver top-notch experiences when it comes to quality, but they achieve this with buffering and adaptive bitrate streaming. While these elements improve the picture quality and performance, they increase the latency.
Instead, you’ll need to use a transport protocol designed for live-streaming content. Here are a few of the best transport protocols to consider:
- Real-Time Messaging Protocol (RTMP): RTMP uses Transmission Control Protocol (TCP) technology to transfer content from an encoder to a digital server. While it provides low-latency streaming, web browsers don’t support playback—so it’ll need to be paired with a playback-friendly alternative.
- WebRTC: WebRTC is a relatively new open-source low-latency solution with support from all the major browsers. However, it’s still expanding to one-to-many use cases and applications.
- Secure Reliable Transport (SRT): SRT is great for high-quality, low-latency streaming but lacks browser support and player customization. Like RTMP, it’s commonly used for ingest and not playback.
4. Give Your Customers the Know-How
Give your users advice on how to improve their stream. Using upgraded hardware and hardwired ethernet connections can enhance latency and streaming quality, as well as closing unused applications.
5. Upgrade Your Live Streaming Setup
The hardware and software you use (and mix together) will have a big impact on the quality and latency of your live stream. Everything from the camera to the encoder to the live streaming platform affects latency—thus, each can be improved to lower your latency and the quality of your stream.
You might even need to upgrade your internet connection to ensure faster upload and delivery. Choose a live-streaming video platform with low-latency streaming—one that uses leading encoders and transfer protocols.
Start Low-Latency Streaming Today
Ready to start low-latency streaming at scale? Get started with JW Player.
We provide the complete video platform for live streaming and video-on-demand (VOD) content. We use a multi-CDN approach (and leading encoding options and transport protocols) to ensure your content travels at standard television broadcast delay.
Give it a try, and see for yourself. Start a 30-day free trial to get full API and SDK access and 75GB of streaming—plenty to test our live streaming functionality and get a first-hand look at our low-latency capabilities.