An overview of the Live Streaming industry
Live Streaming is considered an industrial industry in the future. It attracts major organizations like Facebook, Youtube, Apple, and Adobe 8230; however, prior to online broadcasting (Live Streaming) with standard manager: Coach, DASH, the download speed is usually sent to the host. And with the HTTP-FLV standard, the server will push. This will enhance the maximum experience for the last user when they watch videos on the Website or the business app.
Earlier capturing this potential, many of the CDN services (Content Delivery Network) of the world have applied to HTTP-FLV to please the entertainment markets and OTT network.
Not missing the trend of the world, VNETWORK’s CDN technology also supports HTTP-FLV to ensure a latency of less than 3 seconds to bring excellent quality of Live Streaming service to OTT television and entertainment organizations. such as: POPS WORLDWIDE, Vinh Long Television,…
Outstanding features of VNCDN technology
CDN service with the name VNCDN of VNETWORK is rated as the number 1 CDN technology in Vietnam.
In which, VNCDN is capable of meeting up to 3 million CCUs (concurrent viewers, domestic bandwidth of more than 3Tbps, and CDN Server infrastructure available in 32 countries and territories.
These can be mentioned as follows:
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High-speed Live Streaming & VoD video transmission (ultra-low latency)
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Anti-stealing of token links, effective protection of digital content
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Using new HTTP/3 CDN technology Support for fast data transmission for web browsers with current HTTP/3 applications
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Possessing a huge amount of domestic CDN bandwidth (to more than 3Tbps)
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CDN server network covered 32 countries and territories
VNCDN’s CDN Server network is available in 32 countries and territories
CDN VNCDN supports HLS, RTMP and especially HTTP-FLV
VNCDN brings solutions for CDN, Transcoder, Cloud Storage, and digital content security, making it easier to expand your market and increase your revenue but still save a lot of money.
How CDN support low latency Live Streaming under 3s
The video processing process is done as follows:
Stage 1:
VNCDN’s Live Streaming CDN system will receive input videos (can be VOD - Video on Demand or Video Live Streaming).
Input Video standards are as follows:
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Input Codecs: H.264, AAC
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Input Protocols: RTMP, MPEG-TS IP
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Input Stream: Supports all bitrates (volume of data transmitted in a period of time) ) and resolution
Stage 2:
VNCDN’s Live Streaming CDN system will transcode the input Videos into many different formats, with different sizes. At this time, the transcoder will perform functions such as Transcoding, Trans-site, and Transrate.
Stage 3:
VNCDN’s Live Streaming CDN system completes Video transcoding to standards such as:
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Output Codecs: H.264, AAC
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Output Protocols: RTMP (Real-Time Messaging Protocol), HTTP-FLV, HLS (HTTP Live Streaming)
Output Video format standards suitable for end-user devices such as:
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Live, VOD or HLS
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UHD (Ultra-high Definition)
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HD (High Definition)
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SD (Standard Definition)
Stage 4:
Technology VNCDN’s CDN is used to transmit Video content after they have been transcoded into various formats suitable for the end user’s device. Content is delivered almost instantaneously, thanks to VNCDN’s network of CDN PoPs spanning 32 countries.
To understand how CDN HTTP-FLV technology supports the efficient transmission of Live Streaming Video content, let’s first learn about the protocols used in Live Streaming.
3 main protocols commonly used for Streaming
RTMP (Real-Time Messaging Protocol):
RTMP is a protocol developed by Adobe, used to transmit audio and video with Adobe Flash Player. It’s like 10 years ago when you went to the Internet, you had to install Adobe Flash Player for IE to watch videos. Because at that time flash webs were very popular.
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The advantage of RTMP is very low latency
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The downside is that it is Flash-based
Because nowadays Flash is outdated and fewer and fewer devices support it. In addition, bit-rate streaming is limited, and Apple devices do not support RTMP.
Nowadays browsers don’t need to install Flash player anymore, html5 already supports playing video directly.
Features of RTMP protocol:
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Requires a dedicated web server to deliver the frames of the video the user is currently watching
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Requires a specific server (Wowza, Nginx-RTMP) and protocol (RTMP)
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Process the playback will be interrupted if the connection speed drops below the minimum bandwidth required for the video
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Needs streaming media type like flv
HLS (HTTP Live Streaming)
HLS stands for HTTP Live Streaming, which is a protocol for streaming video across the internet.
Developed by Apple, initially only the iPhone supported this protocol, but today all devices and software support it and it has become the most popular protocol.
HLS is HTTP-based, it uses a web server to transmit content. This means you don’t need to have a dedicated infrastructure just have a web server or use a CDN. Since HLS is HTTP-based, it is also less likely to be blocked by the Firewall.
With HLS, the video will be divided into small segments, which is an adaptive video bitrate method that can choose the appropriate video format (480p, 720p …) for transmission over the Internet depending on your network speed.
Its disadvantage is high latency. For example, when many people are watching football on a certain ABC channel, the ball has gone into the net. But in some other XYZ football channels, there is no signal of the ball entering the net. This is all because the Live Streaming transmission speed in the XYZ football channel has a higher latency than the ABC football channel.
HTTP-FLV
HTTP-FLV is a protocol that supports the delivery of live streams in flv (flash video) format using http. This is a very popular method of media streaming that is used a lot in China because it has the advantage of low latency with rtmp and easy delivery due to using http.
For the server side, the rtmp stream (rtmp stream) is converted to Flv because rtmp is pretty much the only method used for push stream nowadays. For the client side, playing a flv stream is the same as playing a flv video from a static server. However, a player that supports flv is required.
Benefits of HTTP-FLV
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Same low latency as rtmp
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No special protocol needed, much easier than rtmp
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Widely supported flv standard (except apple)
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Support dns 302 redirect
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Less likely to be blocked by Firewall.
Compared to RTMP Streaming, HTTP-FLV is a widely used protocol in China.
HTTP-FLV features
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Use http: no server or special protocol needed, same as the continuous download shown above
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Low latency (better than rtmp)
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Flv is easily created on the fly
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The distinguishing feature of HTTP-FLV is that it has a long connection with a .flv suffix.
Difference between 3 most popular Live Streaming methods: RTMP, HLS, HTTP-FLV
The future of HTTP-FLV
Flash/flv has some disadvantages so it is not supported by apple even adobe has given up developing it. Html5 replaces flash and mp4 replaces flv.
But the biggest advantage of flv is that it is searchable, which means it can start playing from any location in the file. That’s why when we use ffmpeg to push rtmp stream, we should specify the format as flv ( -f flv). In a word, flv is still the main container format used in live streaming to date.
In general, a website that plays live content tends to use a variety of streaming methods in different streams. This is because there is no single method that can work for all platforms and all applications.
Therefore, if you want a Web site or application dedicated to Live Streaming, learn VNETWORK’s CDN Live Streaming technology or register for a trial of HTTP-FLV CDN service. Contact now for advice and support at Hotline: (028) 7306 8789 or contact@vnetwork.vn or email to: sales@vnetwork.vn.