YouTube adopts SRT protocol to bolster low-latency live video ingest
YouTube has officially joined the SRT Alliance to support the open-source Secure Reliable Transport (SRT) protocol for low-latency live video ingest. As part of this initiative, YouTube will participate in the SRT InterOp Plugfest in May 2023 to establish vendor interoperability for live stream contribution into its platform.
Key Takeaways
- YouTube will integrate the SRT protocol to support low-latency live video contribution globally
- Participation in the May 9-11, 2023, SRT InterOp Plugfest will establish multi-vendor hardware and software compatibility
- Move follows SRT's transition to open-source in 2017, now backed by over 700 alliance members
- Implementation targets the 'contribution' stage, enabling more reliable transport over unpredictable public internet paths compared to TCP-based alternatives
Why It Matters
YouTube’s adoption of SRT marks the decline of RTMP’s dominance in high-stakes live contribution. By shifting from TCP-based RTMP to UDP-based SRT, YouTube addresses the inherent latency and jitter issues of the public internet, providing professional broadcasters with a more resilient ingest path. This move validates SRT as the industry standard for low-latency transport, likely forcing remaining hardware and software holdouts to prioritize SRT integration. For the broader ecosystem, it bridges the gap between professional broadcast gear and consumer-scale streaming. Watch for YouTube to potentially deprecate legacy RTMP ingest points in favor of SRT-first workflows as interoperability results from the May 2023 Plugfest are finalized.
Additional Context
The transition to SRT comes at a critical time as broadcasters increasingly pivot away from legacy protocols. Per Haivision’s 2025 Broadcast Transformation Report, SRT usage among broadcasters grew to 77%, widening its lead over RTMP, which fell to 58%. This shift is driven by SRT’s ability to recover from packet loss and support modern codecs like HEVC (H.265) and AV1. While RTMP is limited to H.264, SRT enables higher visual quality at lower bitrates, a necessity for 4K live streaming over unmanaged networks. Competitively, the SRT Alliance continues to face pressure from the Reliable Internet Stream Transport (RIST) protocol. Per the RIST Forum, while SRT is widely adopted in the prosumer and streaming space, RIST is often favored for large-scale professional broadcast due to its support for multi-link bonding and SMPTE ST 2022-7 hitless switching. However, SRT 1.5 recently added connection bonding features to close this technical gap. YouTube's specific endorsement of SRT reinforces the protocol's position as the primary 'on-ramp' for global streaming platforms. Furthermore, the industry is closely monitoring how these ingest improvements affect end-to-end latency. While SRT handles the contribution side, YouTube continues to refine its delivery side via LL-HLS and DASH. Per Google Developers, the platform added support for LL-HLS in 2023 to complement its ultra-low latency ingest initiatives. The combination of SRT for ingest and LL-HLS for delivery allows YouTube to maintain sub-three-second latency while leveraging the scalability of its global CDN infrastructure.
Read full article at srtalliance.org