We’ve all come to rely on video streaming for entertainment, connection, and productivity. But have you ever wondered what makes it possible? The answer is the complex world of video streaming protocols – a combination of technology and innovation that delivers your favorite shows and virtual meetings to your screen.

Let’s take an in-depth look at how these protocols work and what they mean for the future of video streaming.

What Are Video Streaming Protocols?

Nowadays, it’s hard to go a day without streaming video. Many people predominantly watch movies, TV series, live sports, news, and more through on-demand streaming services.

While many take this technology for granted today, it wasn’t always available. Traditional film takes up a great deal of space when converted into digital format. Meanwhile, uncompressed audio and video also take up a huge amount of storage space, and their size makes smoothly streaming them nearly unfeasible. Thus, the rise in popularity of streaming can be attributed to the availability of newer protocols used to break down video files into chunks and deliver them to viewers.

These protocols use compression codecs like H264 to shrink the file size of the videos and store them in a container format (like .mkv or .avi) before they are transferred over the web. Depending on whether you are watching a live stream or VoD (video-on-demand), the source of your video will differ, and the speed and compression requirements will also vary.

The Rise of Video Streaming

Thanks to streaming platforms, entertainment is now available on demand, often in different regions at the same time. Binge-watching has become so popular that it has become part of the popular culture.

Instead of being restricted by a network’s programming schedule, people can now watch whenever they want, whenever they want. More significantly, streaming platforms have made entertainment much more accessible, regardless of income or location, through subscription plans and other options.

Television networks and cable companies have had to find new ways to keep up with the ever-evolving digital space. Some have started their own streaming services, while others have formed collaborative relationships with those that already exist. All this competition has led to an improved level of content available as companies try to hold onto and attract more viewers.

But it’s this rapidly growing demand that has presented challenges for the existing video streaming technology. With increasingly higher definition and the sheer volume of content streamed, the demand for improved streaming protocols is seemingly never-ending.

The Traditional Titans – RTMP and RTSP

Many viewers have probably experienced RTMP (real-time messaging protocol)_and RTSP (real-time streaming protocols) when watching video content online. These traditional streaming protocols are widely accepted due to their reliable performance. They are usually compatible with players that have been around for decades, such as (the recently deprecated but once-ubiquitous) Adobe Flash or Apple QuickTime Player. That said, there are still some drawbacks when using these protocols. For example, RTMP is not the best choice for mobile device streaming, and RTSP often requires additional setup on your firewall. Let’s go deeper into both.

Real-Time Messaging Protocol (RTMP)

Real-Time Messaging Protocol (RTMP) is one of the oldest protocols for live video streaming over the network. It keeps a persistent connection between servers and end destinations, producing solid performance with reduced latency.

Although many browsers and devices no longer accept RTMP, it remains popular for sending video data online due to its reasonably low latency for an old protocol and support for legacy software. Combining RTMP with other streaming protocols may allow for video streaming across various devices from different eras.

Real-Time Streaming Protocol (RTSP)

RTSP is a protocol that lets you control streaming media servers, like turning the TV on or off. To use RTSP, a user sends an RTSP request to the streaming server. This starts the setup process for video and audio streaming. After that, the actual data is sent using RTP. You can think of RTSP as a remote control for streaming media – it helps you turn streams on and off without having to send the data. The RTP protocol does that job instead.

The Up-And-Coming Video Streaming Protocols

As technology evolves, so too does video streaming – meaning more secure and efficient ways to distribute content. Next time you fire up your favorite show or movie, take a moment to appreciate the intricate network of protocols making it all possible.

HTTP Live Streaming (HLS)

HLS stands for HTTP Live Streaming, which is an effort by Apple to make watching video content online much easier. Before HLS, most smartphones used QuickTime Streaming Server as their media streaming standard. Unfortunately, QuickTime depended on non-standard ports for data transfer, and this caused firewalls to block real-time streaming protocol (RTSP).

Apple fixed this by introducing HLS, which uses the web’s native protocol. This means that you can now deploy content using regular web servers and content delivery networks. It works well in wired and wireless connections, automatically optimizing playback speed even when conditions vary.

Faster-Than-Light (FTL)

FTL stands for Faster Than Light—the speed of light, that is. FTL is a live streaming protocol that delivers low-latency streams to devices and platforms like XSplit, OBS Studio, Windows, and Xbox One. It uses two powerful modern video and audio codecs – Opus and H.264 – to provide streams that look and sound crisp, but the tradeoff is lower bitrate than RTMP’s, about 7 Mbps.

Unfortunately, since FTL is still relatively new, it can sometimes be a bit unpredictable. But it’s already been integrated into the Restream ecosystem, so you can count on quality streaming experiences with Mixer and Restream.

Secure Reliable Transport (SRT)

SRT is an open-source streaming protocol developed by Haivision and Wowza, which will likely replace RTMP soon. It offers similar advantages, such as high stability and low latency, making it possible to stream over unreliable networks. A downside is that the playback option isn’t available yet.

The developers claim SRT helps protect live videos from stutters, bandwidth fluctuations, and packet loss. Additionally, it supports real-time communication since its latency is close to FTL and WebRTC. It’s also codec-agnostic, meaning any modern video or audio codec can be used with it. However, note that since this technology is still relatively new, not all platforms have support for SRT yet.

Web Real-Time Communications (WebRTC)

WebRTC stands for Web Real-Time Communications. It works over the web and inside browsers. Every modern browser supports it, so even if you’re using a native application, you can still use WebRTC. This makes communication across different applications and websites much easier.

In the past, if you wanted to build anything with voice or video calling capabilities, you’d have to develop it in C, C++, or similar, which had long development cycles and was expensive. WebRTC changes all that by providing a JavaScript API layer, so developers don’t have to use complex code to build their applications. Although WebRTC is primarily written in C++ internally, many developers won’t need to touch it.

Dynamic Adaptive Streaming over HTTP (DASH) – MPEG-DASH

MPEG DASH uses a single XML-based file, usually with the .mpd extension, and can be used to send protected content through its compatibility with DRM and CENC encryption.

It’s well-supported across many major platforms like YouTube, Netflix, Roku, Chromecast, and Android/Apple ecosystems. Popular media players that support MPEG DASH include VLC Media Player.

Adobe HTTP Dynamic Streaming (HDS)

Adobe HDS is a streaming service that breaks up live videos into smaller chunks and sends them to the player in real time over the internet.

With adaptive bitrate streaming, the video quality will automatically change so viewers have the best possible experience, even with large audiences. Adobe HDS can also be used for DRM protection and to stream videos to places where a Flash Player isn’t available.

The Rise of FAST Channels

Ad-supported streaming television is gaining momentum as subscription plans become more expensive in the era of streaming services. People are actively seeking alternative ways to consume content without incurring additional expenses. This opens up new possibilities for creating protocols that can satisfy both viewers’ needs and maximize monetization opportunities. In other words, it’s no longer just about the technology but also about how videos are delivered.

This has led to the development of FAST (free ad-supported streaming TV) services. These channels allow you to watch traditional TV on your web-connected devices like CTV.

Choosing the Right Protocol

Finding the right streaming protocol to use can be tricky. Each one offers different advantages and drawbacks; which you choose depends on the situation. For example, for broadcasting a live event, SRT or WebRTC might work best as they reduce lag time. On the other hand, if you’re sharing pre-recorded videos, HLS or MPEG-DASH is probably the better choice.

Some of the most popular protocols for streaming video include RTMP (Real Time Messaging Protocol), RTSP (Real Time Streaming Protocol), Apple HLS, Low Latency HLS, MPEG DASH, Low Latency CMAF for DASH, Microsoft Smooth Streaming, Adobe HDS, SRT (Secure Reliable Transport), and WebRTC (Web Real-Time Communication).

Some of these protocols are considered obsolete but still have a purpose in varying scenarios. There are several competing modern standards, so at this point, there is no definitive “ideal” protocol. Factors such as latency, scalability, cost of delivery, consumer device requirements, support for DRM protection, and more affect the protocol of choice for each platform and provider.

Prime Protocol

Video streaming protocols are the foundation of how digital video works, whether you’re an enthusiast or content creator. So, there’s no harm in taking some time to become familiar with them and exploring the vast diversity of protocols.