RTS (RTS) is a value-added feature of ApsaraVideo Live. It provides a live streaming service that features easy client access, ultra-low latency, high concurrency, and smooth high-definition playback. This topic describes the basics and usage of RTS.
Features
RTS builds on ApsaraVideo Live with end-to-end latency monitoring, CDN transport protocol modifications, and underlying technology optimizations such as User Datagram Protocol (UDP). By integrating with the ApsaraVideo Player SDK, RTS supports millisecond-level latency between nodes in scenarios with tens of millions of concurrent users. This addresses the 3 to 6 second latency of traditional live streaming and ensures an ultra-low latency, low stuttering, and fast-loading playback experience.
Certifications
Alibaba Cloud, in collaboration with the China Academy of Information and Communications Technology (CAICT), developed the "Ultra-low Latency Live Streaming Performance and Service Quality Grading Model" and the "Capability Specifications for Transport and Distribution Networks for Real-time Audio and Video" standards. Alibaba Cloud also received an ultra-low latency live streaming evaluation certificate from CAICT. As one of the first companies to be evaluated, ApsaraVideo Live received an "Excellent" rating in the interactive streaming capability assessment, which is the highest rating available. For more information, see Alibaba Cloud Real-Time Streaming receives "Excellent" rating from CAICT.
Architecture
To use RTS, you can add an RTS streaming domain to your existing live streaming service to enable stream pulling with multiple protocols. The following figure shows the architecture.
The stream ingest client continues to use the Real-Time Messaging Protocol (RTMP) for stream ingest. The end-to-end latency is affected by factors such as the network quality of the ingest client, the Group of Pictures (GOP) size of the stream, and the viewer's player cache.
Standard live stream pulling (RTMP, FLV, HLS) uses the original
rtmp://andhttp://formats. RTS stream pulling (UDP) uses theartc://format.
Differences between RTS and standard live streaming
You can smoothly upgrade from standard live streaming to RTS. If you are using the standard live streaming service, you can enable RTS to use both services simultaneously. If RTS playback fails, you can fall back to standard live streaming to ensure service reliability.
Limits
For RTS stream ingest and playback, you must use the Push SDK and the ApsaraVideo Player SDK.
Differences between the solutions
Solution | Real-Time Streaming (RTS) | Standard live streaming |
Ingest protocol | Supports stream ingest over RTMP and Alibaba Real-Time Communication (ARTC). | Supports stream ingest over RTMP. |
Playback protocol | Supports playback of streams over ARTC, which is based on Web Real-Time Communication (WebRTC). | Supports playback of streams over RTMP, FLV, and HTTP Live Streaming (HLS). |
Performance in poor network conditions | Smooth playback is possible with an end-to-end packet loss of 30%. | Limited performance in poor network conditions. |
Compatibility |
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Coverage | Global | Global |
End-to-end latency |
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Best practices |
Differences in scenarios
Streaming type | Scenario |
Real-Time Streaming (RTS) |
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Standard live streaming | Low-interaction scenarios: Primarily for viewing. Video may be out of sync between users due to network differences. |
Demonstration
The following video compares the performance of RTS and standard live streaming:
Scenarios
Scenario | Description |
Education live streaming | Used for large classes. It supports a massive number of students interacting with the teacher online with ultra-low latency. |
E-commerce live streaming | Sellers and buyers interact in real time to answer questions and exchange product information. |
Sports live streaming | Broadcasts exciting sports, e-sports, and other events, allowing viewers to follow the action in real time. |
Interactive entertainment | Streamers can respond instantly when viewers send gifts, which enhances interaction. |
Billing
Unlike standard live streaming, RTS uses a different pricing model. The following rules apply:
RTS is billed based on its own billable items. Billable items for standard live streaming are not included.
Similar to the billing methods for standard live streaming, RTS can be billed by traffic or by bandwidth.
If the billing method for standard live streaming changes, the billing method for RTS also changes.
For more information about RTS billing, see Real-Time Streaming (RTS) pricing.
Try the demo
Use DingTalk to scan the QR code to download and install the RTS demo.
FAQ
Contact us
If you have any questions or suggestions about the RTS (RTS) product, join the DingTalk group by searching for group number 44533142. This group is for technical discussions and Q&A about the RTS product. For product issues or quality tuning, submit a ticket to contact Alibaba Cloud technical support. For more information about how to submit a ticket, see Contact us.