How Does Live Streaming Work? All You Need to Know About the Process

Live streaming is a powerful tool for organizations, with 53% of them using it at least once a year. There's a good reason for this.
Live streams have been more accessible to businesses and individual creators in the last decade or so. And when they're shown to hold viewers' attention 20 times more than on-demand streaming, it's a no-brainer why they're so popular.

But while you may be drawn to the allure of live streaming for your organization, have you ever wondered, 'How does live streaming work?' On the viewer's end, it seems so simple. All they do is load up the streaming site, press play, and enjoy.

On the backend, however, there's a lot that has to take place for the stream to play correctly. Every live broadcaster's biggest fear is that slight misconfiguration or technical glitch that disrupts a meticulously planned stream. The audience leaves disappointed, there's frustration for the broadcaster, and there's embarrassment all around.

Take Apple, for example. Their highly anticipated live-streamed product launch for the iPhone 6 was plagued with constant buffering, low-quality streaming, and technical glitches. Suffice it to say, it's a nightmare scenario for any organization.

This is where many organizations get stuck. They want to leverage the benefits of live streaming, but learning about the technical know-how to set up and optimize that live stream seems daunting. Where do you even begin?

If you find yourself in a similar situation, don't worry. In this blog, we'll dissect the entire live streaming process, from the broadcaster's setup to the smooth playback on viewers' screens. We'll equip you with the knowledge to navigate the technical aspects and ensure a professional live-streaming experience for your organization.

But before diving in, let's review a brief overview of the live-streaming process.

How Does Live Streaming Work: An Overview

Before we dive into the technical inner workings of live streaming, let's take a step back to familiarize ourselves with how does live streaming work from start to finish.

Streaming video, whether live or on-demand, takes much longer than any other form of media streaming. This all comes to the way video works in general. A video is a series of frames stitched together along with accompanying audio. Higher resolutions, higher bitrates, and longer runtimes mean that the video will be much larger in file size and take much longer to stream.

But there's another side to it. When you stream video content, you also have to take into consideration the encoding and decoding processes that will be happening to make the video delivery possible.

When it comes fresh off a camera, video content is still in raw form and can't be streamed as effectively. It needs to be converted into a format that is more easily recognizable by the devices on which it will be played.

Think of it like reading a book. It's not just enough to have all the words in the right order. It would be best to have punctuation and formatting to help your brain parse the text more efficiently. For streaming, the encoding process adds the 'punctuation' to the video data, making it easier for devices to interpret and display the information correctly.

Once the stream is encoded, it's sent over an optimized network of servers called a content delivery network (CDN), which helps cut down on the latency of the live stream.

Lastly, the content is served to the viewer, where the pre-packaged encoded data is decoded and played. In our reading example above, this would be the step where your brain comprehends all the words it just read.

What is Live Video Streaming?

You may already be familiar with live video streaming. If not, we recommend checking out this blog post on what live streaming is and why you should use it. However, let's brush up on the basics, just in case.

Quite simply, live streaming is the process of broadcasting media—in this case, video and audio—to viewers in real time over the internet. This is different from streaming an on-demand video because the content is not pre-recorded and cannot be edited or modified. The video is played almost as soon as it's broadcast (give or take a few moments of delay).

What is Live Streaming Used For?

Video has always been used for several applications. However, advancements in live streaming technology have also made live streaming a popular medium. The real-time nature of live streaming makes it suitable for use cases such as:

Training and Learning

Educational institutes often use live streaming to broadcast lectures, demonstrations, and interactive sessions to distance learning students. With roughly 10 million college students enrolling in distance education in 2022, there is a real need in the education sector for technological solutions like live streaming to overcome educational barriers.

It's a similar case for corporate professionals who need to implement training and learning programs across the workplace. Live streaming helps organizations train their employees using team orientation sessions, hands-on product training, expert talks, and skill development workshops. The live element of live streaming helps feedback and questions to be instantly exchanged.

Corporate Communication

Aside from training, organizations utilize live streaming for corporate communication purposes, such as executive communication with company leaders and senior executives or employee engagement programs instituted by HR departments. They may also use live streams to host company-wide town hall meetings to get everyone on the same page.

Externally, corporate live streaming can be a useful tool for franchise communications, investor relations, investor relations, and even product launches. This can help organizations spread their communications across a wide geographic area, such as live-streamed updates on company policies, change management, or new announcements.

Live Events

Event streaming is one of the most popular use cases for live streaming. In-person events, even in their most ideal form, will have some limitations that prevent them from being accessible to everyone. These reasons can vary from geographical restrictions to scheduling conflicts, budget constraints, or even limitations on the physical capacity of the venue.

Live streaming breaks down these barriers by allowing anyone with an internet connection to participate in the event virtually. For instance, a conference with limited seating can be live streamed to a global audience, offering a wider reach. Using either in-person, virtual, or hybrid live streams, organizations can cater to audiences beyond the limitations of traditional events.

Video Marketing

Video is essential to an organization's marketing efforts, given their success in broadening reach. According to research, 51% of people are more likely to share a video than any other form of marketing content.

In a similar vein, organizations and brands can use live streams to host launch events, stream product demos, host webinars, and conduct other events to create buzz, generate excitement, and foster a more personal connection with their audience.

What Components Are Needed to Make a Live Stream Work?

Here's a question: how does live streaming work to deliver video playback in real-time when the viewer is watching from halfway across the world? Intuitively, it may sound a bit confusing, given that large amounts of video data have to be transmitted seamlessly.

Luckily, advancements in live streaming technology have helped ensure that high-resolution video can be streamed in real-time to audiences across the world. Let's delve into the components that work together to make this real-time experience possible:

Audio/Video Source

Your audio and/or video source is the content you'll be capturing and streaming over the internet. It can be a video camera filming a live event, a webcam for a personal stream, or even a screen capture of your computer for an educational stream.

This source generates the raw audio and video data that will be the foundation of your live stream. The key word here is 'raw' since it has to go through processes before it can be turned into a streamable format.

Encoding

Remember the raw format we just talked about? Encoding is the process that helps 'refine it.' It does this in two major ways. The first is simply converting the raw video input into a more manageable digital form through the use of codecs. This is done to help with the compatibility of the video and make it playable across a range of devices and browsers.

The second part is compression, where the file size of a video is reduced by getting rid of redundant frames and stitching the remainder of the video back together. This helps lower the bandwidth required to stream video content and the storage space requirements of the CDN.

Transcoding

Even in the best of circumstances, live streaming can be prone to delays, buffering, and occasional stops in playback. A broadcaster can go live under the most ideal conditions, but they can't account for the less-than-ideal internet quality of viewers tuning in for that stream.

That's where transcoding comes in. Transcoding creates several renditions of the video in several bitrates and resolutions. This is essential to help make adaptive bitrate (ABR) streaming possible, where the video is switched to a lower quality when internet speeds drop rather than stopping the stream entirely.

There's a lot more to learn about adaptive bitrate streaming. Check out our detailed blog post on what ABR is and how it works to know more.

Live Streaming Protocols

Live streaming protocols dictate how the encoded audio and video data gets packaged, transmitted, and received to ensure a smooth and synchronized playback experience. The live streaming protocols provide the instructions necessary for encoding, transcoding, and adaptive bitrate processes.

Think of these protocols as the code that defines the packaging rules, optimizing, transmitting, and streaming data to the end user. There are several different streaming protocols out there. Each of them works a certain way and has advantages and drawbacks. We'll discuss these in a bit.

Content Delivery Network (CDN)

A content delivery network is a network of geographically dispersed servers that take content from a single origin server and cache it on multiple edge servers so that it can be served to users across the world more efficiently and without the drawbacks of latency.

Say you're a viewer in Japan trying to stream a live video broadcast from the US. Normally, you'd experience high latency, meaning a significant delay as the video data travels a vast distance. This translates to constant buffering and frustrating start-and-stop playback as your video player struggles to keep up with the data stream from the origin server.

With a CDN, however, the scenario changes dramatically. A CDN might have an edge server located in Japan or a nearby region. This geographically closer server would hold a cached copy of the live stream, significantly reducing the distance the data needs to travel to reach your device.

Streaming Server

In a live streaming setup, the streaming server acts as the middleman between the encoder and the content delivery network (CDN). It receives the encoded audio and video data stream from the encoder and prepares it for delivery. This is also where live streaming protocols work their magic to produce video segments of different renditions necessary for adaptive bitrate streaming (ABR).

A streaming server can either be set up on-premises for organizations that require greater control over their data or hosted on cloud infrastructure for those that want to deploy with lower upfront costs and want to keep future-proof scalability in mind.

Live Streaming Platform

A live streaming platform is the final hub where everything comes together. It has all the functionalities needed to manage your live broadcast, connect with your audience, and deliver your content seamlessly.

Often, live streaming platforms will allow you to integrate external encoders and CDNs to make the process a bit simpler. Some platforms will even function as the streaming server by ingesting the encoder feed and pushing it out to their integrated CDNs.

Besides this, live streaming platforms come with additional features like analytics to keep track of the live stream and how it's being viewed, as well as interactivity options like live chats, FAQs, and social media feeds to engage viewers.

Live Streaming Protocols Used in Live Video Streaming

As discussed earlier, streaming protocols define how data is packaged, transmitted, and received to ensure a smooth and synchronized playback experience.

There are different kinds of streaming protocols out there, and they work in different ways, which makes them suitable for diverse applications. Depending on your priorities, you may find certain live-streaming protocols more suitable than others.

With that said, here are some of the most common protocols used for live streaming video content to viewers across the world.

Real Time Messaging Protocol (RTMP)

RTMP was developed in 2002 by Macromedia (now Adobe) to support its Flash Player. At one point, Flash Player was installed in 99% of computers in the Western world. This made RTMP a highly popular video streaming protocol. By 2020, Flash Player was officially retired owing to some security concerns and the rise of HTML5.

Although RTMP is no longer supported, it is still preferred in many organizations due to its ability to deliver low-latency streaming and compatibility with legacy hardware. A workaround called RTMP ingest allows it to be used. You can read more about that in this blog post about RTMP streaming.

The way RTMP achieves its low latency is by streaming video in a sequence of packets rather than segmenting the stream. Moreover, RTMP sends data over TCP instead of HTTP to deliver video streaming.

Real-Time Streaming Protocol (RTSP)

RTSP was developed in the late 90s in collaboration with RealNetworks, Netscape, and Columbia University. Like RTMP, RTSP does not transmit data over HTTP. (Although it works with a client-server process that's very similar to HTTP.)

The main advantage of RTSP is that it boasts lower latency than RTMP. However, this comes as a consequence of security and quality. RTSP cannot stream at a comparable quality to RTMP, and it does not use SSL/TLS encryption to protect streamed video content in transit.

HTTP Live Streaming (HLS)

HLS was developed by Apple in 2009 as a proprietary streaming protocol to replace its QuickTime Streaming Server (QTSS). Currently, it sits as the de facto standard for streaming audio and video content.

The popularity of HLS is rooted in its ability to stream over HTTP, which allows it to be streamed directly within web browsers. This makes it compatible with a wide range of devices. What's more, it includes support for adaptive bitrate streaming (ABR).

If HLS has a drawback, it's that it has a relatively high latency when compared to other streaming protocols. Luckily, Apple continually brings updates and improvements to HLS and has even created a low latency variant of HLS called Low Latency HLS (LL HLS).

Despite the high latency, HLS continues to be a popular choice for video streaming due to its impressive capabilities. In fact, some legacy streaming protocols, such as RTMP ingest or FFMPEG conversion in the case of RTSP, continue to exist today thanks to their conversion to HLS.

Dynamic Adaptive Streaming Over HTTP (MPEG-DASH)

Like HLS, DASH is another popular video streaming protocol that uses HTTP for data delivery. It was developed in 2012, just a short while after HLS entered the streaming market. DASH was developed by the Moving Picture Experts Group, an alliance of industry giants and experts established by ISO and the IEC.

DASH was developed to be an open-source, standardized protocol that is codec-agnostic and built upon the same functional benefits of DASH, like ABR support. The one shortfall of using DASH is that Safari does not support it.

Web Real-Time Communication (WebRTC)

WebRTC was first developed by Global IP Solutions (GIPS) in 1999, but it didn't gain significant traction until 2011 when Google released an open-source project for browser-based real-time communication.

Like MPEG-DASH, WebRTC is a free and open-source protocol that relies on peer-to-peer (P2P) data transmission to avoid the use of plugins or apps. It boasts impressive sub-second latencies, making it one of the fastest live streaming protocols and ideal for real-time streaming.

Although the secret to WebRTC's low delay is its use of P2P, that's also its downfall. The reliance on P2P means that the number of concurrent connections that it can establish is limited, which is a problem for scalability. This makes WebRTC suitable for live streaming where the viewer count is around 50 or lower.

The Live Streaming Process Explained In Depth

Now that we've mastered the fundamentals of live streaming, we can finally address the burning question: How does live streaming work on a technical level?

Believe it or not, despite all the technicalities and minor details involved, the live-streaming process can actually be fairly straightforward to understand. So, without further ado, let's find out the details of what makes a live stream tick.

Feed Capture

A live stream starts with capturing the raw audio and video data, often referred to as the "feed." The capture process depends on the type of audio/video source you're using.

In a very typical scenario, the light from the scene hits the digital camera sensor. The resulting image then undergoes an analog-to-digital conversion. At this point, even though the signal output is in a digital format, it is still considered 'raw' due to its large size and unoptimized state. This raw digital data isn't ready for efficient transmission over the internet for live streaming.

Encoding and Compression

After the recording device outputs the video feed, it is sent to the encoder for further processing. Encoders can come in different shapes and sizes, from dedicated hardware to software and even cloud encoders.

As we discussed earlier, this is the step where the video feed is made a bit more 'manageable' for transmission and streaming. The encoder does this in two concurrent steps: encoding and compression. The encoder processes the video frames in chunks called macroblocks, i.e., 16x16 displayed pixels.

In order to reduce the file size of the raw video, the encoder packages it with the help of an encoder. Common encoders for live streaming include H.264, H.265, VP9, and AV1. The way each encoder compresses data depends on the specific encoder.

For instance, H.264 uses a combination of different compression techniques like interframe compression, motion compensation, quantization, and entropy coding. These techniques utilize different processes, but the end goal is to reduce the amount of data without making changes that drastically affect the quality noticeably.

Here's an example. Say you have a live stream of a presenter against a static backdrop. The presenter may move around during the stream, but the backdrop will remain the same and won't require individual rendering for each frame.

Here's a breakdown of how common compression techniques work:

Interframe Compression

This technique analyzes the differences between consecutive video frames. Instead of repeatedly storing entire frames, only the changes between frames are saved. This is highly effective for videos with minimal scene movement, as less data is needed to represent the changes.

Motion Compensation

Building upon interframe compression, this technique analyzes camera movement within the video. Instead of storing entire frames with slight object movement, the encoder calculates the motion and stores only the information needed to adjust the position of objects within the previous frame.

Quantization

Quantization works on a technical level to reduce the data needed to represent the video. Instead of storing exact values of wide ranges of data, they are scaled and rounded down to simpler, smaller values.

Entropy Coding

Entropy coding recognizes patterns in video data. The more frequently occurring patterns are represented by more bits, and the less frequently occurring patterns are presented by fewer bits.

Of course, several other techniques depend on the specific codec being used. The other part of this process, the encoding itself, helps the video be compatible with a variety of devices and ensures that playback is supported. To play it, the user's device will need to 'decode' it again.

Segmentation

Streaming through modern protocols like HLS and MPEG-DASH requires the delivery of chunks of videos that can be sent to the video player to ensure efficient streaming. Segmentation involves dividing the encoded video stream into smaller chunks of data called segments. These segments typically range from a few seconds to ten seconds in length. (The length ultimately depends on the specific streaming platform and encoding settings.)

Transcoding

We discussed the importance of adaptive bit rate (ABR) streaming earlier and how it helps ensure a seamless streaming experience for the user. Transcoding is a critical process that makes ABR possible.

This step aims to create multiple renditions of the video with different bitrates and resolutions. These processes are called trans-rating and trans-sizing, respectively. Here are the steps involved in a typical transcoding process:

De-Muxing

First, the transcoder analyzes the encoded file segments to locate the video and audio streams. Once identified, they are separated into individual components for processing. This separation is necessary because audio and video streams undergo different compression processes.

Decoding

Next, the transcoder decodes the separated video stream into an intermediary format like YUV or RGB. It reverses the encoding processes, such as inverse quantization, to recover the original pixel values for each frame. This reconstructs the video.

Post-processing

This is the step where the video undergoes changes like trans-sizing to change the video frame to different resolutions. At this point, the video is still uncompressed.

Re-encoding

With the desired modifications applied, the video data is compressed and re-encoded using a chosen codec at the target bitrate and resolution. This creates a new rendition of the video stream optimized for a specific audience segment.

Muxing

Finally, the file is reassembled with the video and audio streams and any metadata that needs to be attached.

Manifest File Creation

If you remember, we created video segments earlier in this process to help with ABR. The only problem is, how does a video player keep track of so many different segments?

The answer is the manifest file.

After transcoding the video file, but before repackaging it, the system creates a manifest file to map out all the different video segments of each bitrate and resolution. This helps the video player and server track which segment to deliver and stream next.

The system creates manifest files (also known as playlist files) in the .m3u8 format. There can be a single primary manifest file or two manifest files—the primary manifest and the media manifest—mapped out to the master manifest file.

Primary Manifest

This is the first file that the video player requests. The primary manifest contains information about all the possible video streams available. It lists the video resolution of the streams, the bandwidth required to stream them, and the decoder required for compatible playback. In the case of only a primary manifest, it also contains information about the segments.

Media Manifest

The media manifest contains information about the duration and the URL of each playback segment.

There can be other types of manifest files for different streaming protocols, such as Media Presentation Documentation (MPD) in the case of MPEG-DASH.

Progressive Delivery to CDN

After transcoding and segmentation, the video stream is typically packaged using a container format like MPEG-TS (Transport Stream). This format efficiently organizes the video segments, manifest files, and other metadata into a single streamable unit. This is then sent to an origin server, which acts as a central repository to store the data. However, it only stores this data and doesn't stream it directly to users.

The origin server transmits the packaged stream content to edge servers using protocols that are optimized for efficient delivery of live streaming data like HTTP Live Streaming (HLS).

Caching on Edge Server

As edge servers start receiving data from the origin server, they utilize various caching mechanisms to store the content locally. These mechanisms can involve caching entire segments, specific data chunks within segments, or using techniques like byte-range requests to efficiently serve only the necessary data for each viewer.

Since live streams are constantly updated with new segments, there are often mechanisms in place to invalidate outdated content from the edge server cache, like Time-To-Live (TTL) values or invalidation messages from the origin server. This ensures viewers receive the latest version of the stream.

Video Delivery

As the viewer loads up a live video stream on their player, it requests the manifest file from the CDN. The video player evaluates the size of the playback window and the network speed to determine the appropriate quality of the video rendition it needs.

Once the video player determines the requirements, it requests the desired video segment from the CDN. The CDN reroutes this request until it reaches the closest geographic edge server, which then establishes a persistent TCP connection to the viewer to ensure the continuous delivery of the stream without any stopgaps.

The video player will usually look up the appropriate sequence of the video segments and request two or three of them at a time from the edge server. Upon receiving this request, the edge server checks if it has that particular video segment available. If the segments are found in the cache (a "cache hit"), it serves it to the viewer. If it doesn't (a "cache miss"), it requests it from the origin server.

Decoding and Playback

Once the video player receives the video segments, it uses the appropriate decoder (based on the chosen codec specified in the manifest file) to convert the compressed video data back into a streamable format.

As the stream starts, the player assembles and plays back the segments in the appropriate order listed in the manifest file. The video player makes sure it has a store of the segments it received. As playback progresses, the player decodes and displays video frames from the buffer. It also requests new segments from the CDN edge server to keep a buffer ahead of playback.

When the internet connection quality changes, the player requests higher or lower bandwidth segments from the edge server. Of course, playback can sometimes have errors, and the stream can be lost in transit. When that happens, the player re-requests and re-delivers it from the edge server.

How Does Live Streaming Work on Live Streaming Platforms?

We've unpacked the technical journey of how a live stream works from start to end. If you're still with us, we just need to go over the last piece of the puzzle—live streaming platforms. But what are live streaming platforms? And how does live streaming work with them?

Live streaming platforms simplify broadcasters' workflows by providing a user-friendly interface for managing streams and interacting with viewers. These platforms offer features for scheduling live streams in advance and promoting them to generate anticipation among viewers.

What's more, a live streaming platform offers interaction and audience engagement using interactivity options like live chat, FAQs, Q&As, and social media feeds. This allows viewers to participate and actively ask questions in real time.

Besides this, these platforms also come with analytics to track viewer data during the live stream. This gives organizations data to monitor and refine their content strategies.

Lastly, live streaming platforms make content sharing a breeze. Features like social media sharing buttons allow broadcasters to easily promote their live streams across various platforms. This helps them expand their reach and attract new viewers.

Go Live Effortlessly with EnterpriseTube

Live streaming may seem easy on the surface until you look at the process under the hood. There can be a lot of moving parts and complexities that are hard to account for. While understanding how does live streaming work is important, so is having all the necessary components to make it work.

Traditional live-streaming workflows can be complex and require several technical considerations. But it's that last-mile delivery that's crucial. You could have a live stream set up perfectly from the start. However, if your end-user experience is not up to par, it could leave your viewers to drop off.

This is where live streaming platforms come in. They simplify the process and empower organizations to leverage the power of live video. These platforms offer viewers an easy interface to navigate through, built-in features for live interactions, and analytics to track performance.

EnterpriseTube takes live streaming a step further, specifically catering to the needs of businesses and organizations. As a platform, it offers robust security features, secure delivery options, and scalability to handle large audiences.

Whether you're hosting a product launch, conducting training sessions, or delivering internal communications, EnterpriseTube empowers you to create professional and engaging live streams that reach your target audience effectively. And after the live stream, you can host the recordings for on-demand viewing.

Ready to take your live streaming efforts to the next level? Sign up for a 7-day free trial, or contact us to learn more.

People Also Ask

How does live streaming work?

Live streaming works through a process of encoding, transcoding, and CDN video delivery to distribute live video content to viewers. It uses a combination of encoders, live streaming protocols, and CDNs to achieve this.

What is live streaming technology?

Live streaming technology allows real-time video transmission over the internet. It involves encoding, packaging, delivery via CDNs, and playback on viewers' devices.

What is corporate live streaming?

Corporate live streaming uses live video for business purposes like product launches, training sessions, or internal communications.

What do I need to start streaming video live?

To start streaming video live, you will need a video source, an encoder, a CDN, a streaming server, and a live streaming platform.

What are live streaming platforms?

Live streaming platforms offer tools for broadcasters to manage live streams. They also allow broadcasters to interact with viewers and track analytics. They simplify the live streaming workflow and offer features for viewers to watch and participate.

What is live video streaming?

Live video streaming transmits video content over the internet in real time. This lets viewers watch the video as it's recorded.