This topic describes how to prevent stuttering and network instability and accelerate live streaming when the streamers and viewers reside in different countries/regions.
Differences between live streaming in and outside the Chinese mainland
Compared with live streaming in the Chinese mainland, live streaming outside the Chinese mainland has the following requirements:
Acceleration region and live center of domain names and uplink and downlink monitoring
When you stream across different countries/regions, you must select the most suitable acceleration region and live center to prevent unstable transmission and mitigate video stuttering.
You can monitor the uplink frame rate and bitrate to check the live streaming status of streamers in real time, and collect downlink playback statistics to understand viewer behaviors.
Qualifications, including Internet Content Provider (ICP) filings for domain names
To use a domain name to provide live streaming services for viewers in the Chinese mainland, you must apply for an ICP filing for the domain name, regardless of whether the streamers reside in or outside the Chinese mainland.
Features of ApsaraVideo Live for live streaming outside the Chinese mainland
ApsaraVideo Live allows you to encrypt live streams outside the Chinese mainland, especially in scenarios in which the live streams are ingested and played outside the Chinese mainland.
ApsaraVideo Live supports adaptive bitrate streaming depending on the network conditions. Adaptive bitrate streaming meets the requirements for long-distance transmission over cross-border links.
ApsaraVideo Live provides a Secure Reliable Transport (SRT)-compliant solution for cross-border live streaming of National Radio and Television Administration (NRTA) regulation-based activities, events, and concerts.
Solutions for different scenarios in terms of network link optimization
Live streaming outside the Chinese mainland
Problem description
Viewers are widely distributed around the globe, and your streams cannot reach all of the viewers.
The locations of streamers are not fixed. In addition, the network transmission is unstable, and the live streaming quality is low.
Live streams are easily affected by poor network conditions due to long transmission links. As a result, stuttering occurs.
Solution
ApsaraVideo Live provides live centers in the Germany (Frankfurt), Singapore, and Japan (Tokyo) regions for streamers outside the Chinese mainland. We recommend that you select a live center that is nearest to the streamers. Then, ApsaraVideo Live can ingest streams to the live center.
Configure edge ingest.
Alibaba Cloud CDN provides edge nodes that cover most countries and regions. ApsaraVideo Live uses edge ingest to deliver streams to the edge nodes that are nearest to the streamers. Then, ApsaraVideo Live uses the network that is optimized by Alibaba Cloud to deliver the streams to the live center that you specify.
NoteApsaraVideo Live uses edge ingest to distribute content for streaming domains that are added after February 21, 2019. If you are still using live center ingest, you must switch to edge ingest. To do so, submit a ticket. For more information about how to submit a ticket, see Contact us.
Monitor the network conditions in real time.
To monitor the network conditions of a streamer in real time, perform the following steps: Log on to the ApsaraVideo Live console. In the left-side navigation pane, choose . On the Stream Management page, click the Active Streams tab and find the domain name that you want to query. Then, click Stream Monitoring in the Actions column to check the stream ingest status and network conditions of the streamer in real time. This helps ensure the stability of stream ingest. For more information, see Manage live streams.
You can also call an API operation to query the frame rate and bitrate of a stream in real time. For more information, see DescribeLiveDomainFrameRateAndBitRateData.
If your live streams stutter frequently, you can activate https://www.alibabacloud.com/zh/product/ga based on your business requirements. You can also submit a ticket to contact us for link optimization.
Features of ApsaraVideo Live for live streaming outside the Chinese mainland
Content security
ApsaraVideo Live supports Alibaba Cloud proprietary cryptography. Live streams are encrypted in live centers based on the cooperation between the server and players. In addition, Key Management Service (KMS) is used to dynamically manage keys. To decrypt and play live streams, you must use a player that is allowed by the server. For more information, see Alibaba Cloud proprietary cryptography.
Adaptive bitrate streaming
If the uplink network conditions permit, you may be inclined to set parameters to values that can produce a higher definition. For example, you set a higher bitrate. However, network conditions are complex and changeable. To meet downlink playback requirements in a variety of environments, you can enable adaptive bitrate streaming. This way, live streams are played at an appropriate bitrate based on the viewers' network conditions. After you enable adaptive bitrate streaming, the player automatically selects the best definition when the viewers start to play a live stream. When the player detects that the viewers are in poor network conditions, the player switches to playing the live stream at a lower bitrate.
RTS
The RTS feature supports end-to-end live streaming with a latency of 1.5 seconds. Uplink streams are ingested based on Real-Time Messaging Protocol (RTMP). In terms of downlink stream playback, the Alibaba Real-Time Communication (ARTC) protocol is supported in addition to RTMP, Flash Video (FLV), and HTTP Live Streaming (HLS). ARTC is evolved based on open source Web Real-Time Communication (WebRTC). You can add sub-streaming domains to ensure ultra-low-latency streaming based on ARTC. You can use ApsaraVideo Player SDK, RTS SDK for .NET, or a third-party SDK to integrate RTS into your business logic. The time required for instant loading and the stuttering rate of RTS are less than or equal to those of RTMP-based streaming. For more information, visit the RTS page.
Low-latency HLS (LHLS)
LHLS is developed to reduce the latency over the HLS protocol. LHLS can reduce the latency of HLS from a range of 15 to 30 seconds to a range of 3 to 5 seconds.
Live streaming based on SRT and Dolby Atmos
This feature is applicable to the live streaming of professional, large-scale NRTA regulation-based events. For more information, see Live streaming based on SRT and Dolby Atmos.