8 Common SRT Myths Busted
Since its initial creation and subsequent open source release two years ago, the Secure Reliable Transport (SRT) protocol has been steadily gathering momentum within the broadcast and video streaming industries. Designed to enable secure and reliable transport of data across unpredictable networks, SRT is particularly optimized for live video streaming and is shaping the future when it comes to easing the transition to IP based solutions. In this post we set out to debunk some of the most common myths that continue to surround SRT. In no particular order, here they are:
SRT Myth #1: SRT Is Not Widely Adopted
From broadcast heavyweights Sky News, Fox News and NBC Sports to industry giants such as Avid, MediaKind and Microsoft, SRT is everywhere. Endorsed by growing user and developer communities along with adoption by open source initiatives VLC, GStreamer, Wireshark and OBS Studio, SRT is fast becoming the de facto low latency video streaming standard for the broadcast and streaming industries. There are well over 200 active members (and growing) of the SRT Alliance along with hundreds of SRT ready solutions – from cameras, encoders and decoders to gateways, OTT transcoding services and CDNs. SRT is currently deployed by thousands of organizations globally in a number of applications and markets. Don’t just take our word for it, read more about how SRT has been making waves in the industry since its public launch at NAB in 2017.
SRT Myth #2: I Need to Buy a License to Use SRT
Not to be confused with other expensive and closed proprietary protocols, SRT can be implemented using a free, open source code base, keeping costs low for all parties. There are no royalties, long-term contracts or monthly subscription fees required. Being open source encourages SRT’s widespread adoption and helps to ensure both interoperability and longevity for end users while avoiding vendor “lock-in”. It’s collaboration at its finest.
SRT Myth #3: SRT Doesn’t Support All Video Codecs
Unlike some other protocols that only support specific video and audio formats, SRT does not limit you to a specific container or codec, since it is media or content agnostic. SRT operates at the network transport level, acting as a wrapper around your content. This means it can transport any type of codec, resolution or frame rate. This is important because it can future proof workflows by working transparently with MPEG-2, H.264, and HEVC for example.
SRT Myth #4: SRT Can’t Stream 4K Video Over the Internet
See myth #3. SRT is content agnostic and can fully support 4K UHD and HD video. For example, Haivision’s Makito X4 video encoder designed for ultra low latency 4K and HD video includes native support for the SRT protocol. This makes it ideal for streaming over unpredictable networks such as the public internet. With built-in AES 128/256-bit encryption, SRT allows Maktio X4 users to keep their valuable 4k content safe and secure.
SRT Myth #5: SRT Can Only Be Used Over the Internet
While it’s true that SRT was originally designed to address the main challenges of streaming video content over the internet, once it was open sourced, developers began implementing SRT on their own hardware and software stacks for all types of networks. Beyond the public internet, SRT can also be used over managed networks such as MPLS as well as satellite, SD-WANs and cellular networks. You can read more about just how versatile SRT is in this blog post: Using SRT to Live Stream Over the Internet and Other Networks.
SRT Myth #6: SRT Doesn’t Support OTT Workflows
Quite the contrary! In the race to bring OTT latency down to linear television levels, SRT has a critical role to play. Although the battle for low latency streaming is heating up at the last mile, where content is delivered to screens for viewing, the truth is that the low latency win begins much earlier, at the first mile. When covering remote events, the first mile of streaming consists of capturing content from a camera, encoding it over h.264 or HEVC and streaming it over an IP network to a production facility. Also called broadcast contribution, this stage is critical in managing overall end-to-end latency and SRT includes major features that are ideal for the first mile, including low latency packet loss recovery and content encryption. The bottom line? SRT is the ideal first mile to distribution streaming protocol, keeping latency low all the way to the final last mile stage of OTT transcoding to ABR streams in HLS, MPEG-DASH, and CMAF.
SRT Myth #7: SRT Isn’t Interoperable With RTP
SRT allows you to transmit RTP payload reliably and securely, so you can absolutely leverage SRT while maintaining your existing RTP-based broadcast infrastructure.
SRT Myth #8: SRT Only Supports up to 30 MBit/s Bitrates
There used to be a default setting in SRT that set the maximum bandwidth to be used by SRT to 30 MBit/s. This was simply the default and could be set to any other value, e.g. 100 MBit/s for supporting lightly compressed contribution video and 4K UHD workflows or 5 MBit/s for low-bandwidth streaming. In the latest SRT version (1.3.3) the default value has been raised to 1 GBit/s.
Get the facts about the SRT protocol, download your copy of the SRT Protocol Technical Overview for more detailed insights into the unique capabilities of SRT.