Q: What are the main causes of latency in live streaming?

1. Method of capture A delay at the source because of the capture workflow of the publisher’s environment. For example, a video publisher may have pre and post processing requirements which cause the stream to be delayed before being sent to the receiving endpoint. 2. Encoding It takes time for an encoder to receive the stream, process it, and output the new stream for delivery. Encoding can take place at the source of the capture or in the cloud, both cases will produce some delay. 3. Method of delivery A traditional CDN will need to cache live stream segments on a global network before they are able to be delivered to viewers over HTTP, this will generally add 30-60 seconds of latency to a live stream. Specialized network deployments are required to deliver sub-second latency streaming at scale.

Q: For ultra-low and real-time latency, what are the advantages Dolby.io Real-time Streaming?

• No setup required, instant activation Simply activate your account and you can begin streaming to your audience instantly, at any scale. • Affordability The time, money and risk required to properly configure, deploy, scale and manage your own infrastructure is far more expensive than a hosted solution like Dolby.io Real-time Streaming. • Scalability Dolby.io Real-time Streaming has a true global CDN, allowing you to scale your stream to over 100,000 concurrent users. • Security To properly secure your streams and infrastructure from unauthorized access requires advanced knowledge and experience. With Dolby.io Real-time Streaming this is built into the service by industry experts who understand the importance of securing your streams. • Future proof Regardless of changes to device support, browsers or protocols, updates to the service are updated and deployed for you with no extra cost, time or attention required.

Question 1

What is real-time/ultra-low latency streaming?

Accepted Answer

Many of us have heard buzz words being thrown around in the streaming industry like “low latency,” “ultra low latency,” and “real-time latency” but many are still confused about what these terms mean, and are curious if latency is important for their streaming initiatives.

This FAQ is meant to cut to the point and answer the most important questions, in a simple and straightforward way.

Question 2

What is Millicast?

Accepted Answer

You may see Millicast mentioned in our product pages and documentation. Millicast is a real-time streaming provider that was acquired by Dolby.io in February 2022. Through Dolby.io Streaming you can access all of the power of the Millicast real-time streaming platform as well as the integrations with Dolby.io’s Communications and Media APIs.

Question 3

What is latency and why is it important for streaming video?

Accepted Answer

Latency in streaming is the time it takes for a live video stream to get from the point where a camera captures the live feed, to the device where the stream is viewed. Sometimes this is referred to as “glass-to-glass.”

Latency is important when a live video feed is time-sensitive and viewers must receive the live content in a short and predictable amount of time, like an online auction for example.

Question 4

What is the difference between low latency streaming and real-time video streaming?

Accepted Answer

Low latency streaming is typically video being delivered from capture to viewer in under 10 seconds. Ultra-low latency streaming is typically under 5 seconds. Both of these use traditional HTTP streaming protocols like HLS or MPEG-DASH.

Real-time video streaming, on the other hand, aims to re-create live human interaction which requires less than 1 second from the source to the viewer. For specific use cases, like cloud gaming, the target is even faster, with 100-500 milliseconds of round-trip time to create the user experience needed for 2-way interactivity.

Question 5

Who is real-time streaming for?

Accepted Answer

Real-time streaming is especially important for live auctions, AR, VR, metaverse, financial news, live events, gaming, sports, trivia, and other cases where time-to-delivery and synchronicity of the live stream is mission critical.

Question 6

What are the main causes of latency in live streaming?

Accepted Answer

1. Method of capture
A delay at the source because of the capture workflow of the publisher’s environment. For example, a video publisher may have pre and post processing requirements which cause the stream to be delayed before being sent to the receiving endpoint.

2. Encoding
It takes time for an encoder to receive the stream, process it, and output the new stream for delivery. Encoding can take place at the source of the capture or in the cloud, both cases will produce some delay.

3. Method of delivery
A traditional CDN will need to cache live stream segments on a global network before they are able to be delivered to viewers over HTTP, this will generally add 30-60 seconds of latency to a live stream. Specialized network deployments are required to deliver sub-second latency streaming at scale.

Question 7

What low latency streaming technologies are currently available?

Accepted Answer

WebRTC technology was originally developed for “real-time communication” in a browser, which is essentially live video conferencing. However, WebRTC has evolved tremendously to become the de facto standard for publishing and playback of real-time, sub-second live streaming.

Dolby.io Real-time Streaming product is built on Millicast technology, which uses WebRTC to support large-scale live broadcasting with sub-second latency audio and video streaming.
Historically RTMP (Real Time Messaging Protocol) was the standard for low and ultra-low latency streaming. The RTMP protocol is still used today for live publishing. However, it is now obsolete for playback because it requires the Adobe Flash plugin which disappeared in April 2020.

SRT (Secure Reliable Transport) is a protocol developed by Haivisionis not supported natively in the web browser and not designed to scale to large audiences.

Other low-latency protocols and formats include CMAF, Apple Low Latency HLS (LL-HLS), and QUIC. However, these protocols are not yet accepted standards.

Question 8

What are my options for low latency streaming?

Accepted Answer

There are several options, the best solution for you depends on your use case and requirements. If 30-60 seconds latency is acceptable for your stream, you can use just about any existing solution on the market from CDN providers. If you need better than 30 seconds there are specialized media server software providers which can help you solve this problem.

If you want true real-time latency, Dolby.io Streaming is a fully managed solution, which includes provisioning features and dashboard i.e. configuring, deploying, and managing your streaming business with guaranteed uptime.

Question 9

For ultra-low and real-time latency, what are the advantages Dolby.io Real-time Streaming?

Accepted Answer

• No setup required, instant activation
Simply activate your account and you can begin streaming to your audience instantly, at any scale.

• Affordability
The time, money and risk required to properly configure, deploy, scale and manage your own infrastructure is far more expensive than a hosted solution like Dolby.io Real-time Streaming.

• Scalability
Dolby.io Real-time Streaming has a true global CDN, allowing you to scale your stream to over 100,000 concurrent users.

• Security
To properly secure your streams and infrastructure from unauthorized access requires advanced knowledge and experience. With Dolby.io Real-time Streaming this is built into the service by industry experts who understand the importance of securing your streams.

• Future proof
Regardless of changes to device support, browsers or protocols, updates to the service are updated and deployed for you with no extra cost, time or attention required.

Streaming APIs

Real-time Streaming

Real-time Latency

Device Compatibility

Broadcast Quality

Affordability

Scale Reliably