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ApsaraVideo Live:Overview

Last Updated:Apr 10, 2024

Real-Time Streaming (RTS) is a premium feature of ApsaraVideo Live. This feature provides easy-to-access live streaming services characterized by ultra-low latency, high concurrency, high definition, and smooth playback. This topic describes basic information about RTS and how to use the feature.


On top of ApsaraVideo Live, RTS provides enhanced streaming performance through various approaches. It supports latency monitoring throughout the live streaming process, revamps CDN transmission protocols, and optimizes underlying technologies such as User Datagram Protocol (UDP). RTS also integrates ApsaraVideo Player SDK. Compared with conventional live streaming that has a latency of 3 to 6 seconds, RTS can support the playback of tens of millions of concurrent streams at a latency of milliseconds. This ensures that the streams load instantly and play smoothly.


To use the RTS feature, you only need to add an RTS streaming domain to ApsaraVideo Live. Then, you can pull streams over various protocols. The following figure shows the architecture of RTS.

  • Streams are ingested over Real-Time Messaging Protocol (RTMP). The latency of streams depends on the network quality for stream ingest, the Group of Pictures (GOP) size of the streams, and the player cache.

  • For standard streaming over RTMP, the streaming URL starts with rtmp://; for standard streaming over Flash Video (FLV) or HTTP Live Streaming (HLS), the streaming URL starts with http://. For RTS over UDP, the streaming URL starts with artc://.

Differences between RTS and standard streaming

You can seamlessly upgrade from standard streaming to RTS. If you are using standard streaming, enable RTS in the ApsaraVideo Live console to use standard streaming and RTS at the same time. If RTS encounters playback failures, you can revert to standard streaming to ensure business reliability.


  • RTS 2.0 must be integrated on both the stream ingest side and playback side.

  • RTS 1.0 must be integrated on the playback side.

Feature comparison



Standard streaming

RTS 2.0

RTS 1.0

Streaming protocol

Alibaba Real-Time Communication (ARTC), a protocol based on Web Real-Time Communication (WebRTC)



End-to-end latency

200 to 400 ms

500 to 1,000 ms

  • Streams over RTMP and FLV: 3 to 6 seconds

  • Streams over HLS: at least 10 seconds

Resistance to poor networks

Smooth playback even at an end-to-end packet loss rate of 30%

Smooth playback even at a playback-side packet loss rate of 30%

Limited performance under poor network conditions


  • Native: RTS 2.0 is compatible with mainstream operating systems.

  • Web: The device compatibility rate is greater than 98%.

  • Native: RTS 1.0 is compatible with mainstream operating systems.

  • Web: The device compatibility rate is greater than 98%.

  • HLS: Standard streaming over HLS has good compatibility.

  • RTMP: Standard streaming over RTMP has poor compatibility. We recommend that you not use RTMP for playback.

  • FLV: Standard streaming over FLV has poor compatibility with HTML5 on mobile clients.





Best practices

A live streaming latency of 200 to 400 ms is achieved. For more information, see Reduce the latency to 200 to 400 ms.

A live streaming latency of 500 to 1,000 ms is achieved. For more information, see Get started with RTS.

For more information, see Get started with ApsaraVideo Live.

Scenario comparison




  • High user interaction: RTS is commonly used for e-commerce, chat groups, education, and corporate live streaming. Its low latency and high interactivity help improve lead conversion and user engagement.

  • Synchronized viewing: RTS is also commonly used for sports live streaming. It provides real-time on-site updates and maintains screen consistency for all viewers.

Standard streaming

Minimal user interaction: Standard streaming enables viewers to watch streams, but varying network conditions can result in inconsistent viewing experiences across different screens.

Performance showcase

The following video shows the performance improvements of RTS over standard streaming:




Education live streaming

In online large classes, a large number of students can interact with teachers at a low latency.

E-commerce live streaming

Sellers can communicate with buyers, answer questions from buyers, and exchange product information with buyers in real time.

Sports live streaming

Sports and e-sports events are broadcast in real time.

Interactive entertainment

Streamers can give real-time response when viewers send virtual gifts, which creates a more interactive and engaging experience.


The billing of RTS is different from that of standard streaming. The following rules apply:

  • You are charged based on the billable items of RTS rather than those of standard streaming.

  • The metering methods for RTS and standard streaming are the same. You can pay for RTS by traffic or bandwidth.

  • If you change the metering method for standard streaming, the metering method for RTS also changes.

For more information about the billing of RTS, see Billing of RTS.


To download RTS demos, use DingTalk to scan the following QR code:




If you have questions or suggestions when you use RTS, join the DingTalk group (group ID: 44533142) for RTS technical support. For troubleshooting and quality tuning, submit a ticket to contact Alibaba Cloud technical support. For more information, see Contact us.