Once the 실시간중계 has undergone segmentation, compression, and encoding, which takes just a few seconds, it has to be made available for the various viewers who are in millions who want to watch your content. To be able to maintain the high quality that has minimal latency, while at the same time ensuring you serve a stream to a variety of viewers who are in different locations, there is a need for CDN.
CDN refers to a distributed network of servers that can cache and serve on behalf of the initial server. When a CDN is used, it creates a performance that is faster because the requests of the user will not have to travel several miles to the initial server but will be taken care of by the CDN server.
Being able to handle requests and deliver content in this manner to various users across the globe ensures the initial server is not overloaded. The content is efficiently served to users worldwide because there are servers dotted around the world instead of one in a specific geographical area.
A CDN can cache, which is to save each live stream segment meaning temporarily, most viewers will be watching the live stream from the cache of the CDN instead of coming from the main server. It makes the live stream real-time, even though what is cached is typically a few seconds behind. It is so because it can cut on some to and fro trips of video from the main server.
Why use CDN for live stream
Bandwidth
Bandwidth is the given point on a network that allows a specific amount of data to pass through. If a data stream gets to a point on the data amount that exceeds capacity, it is referred to as a choke point as the data that is supposed to be delivered tends to be choked off, causing it to slow down. It can be compared to when traffic slows down the movement of vehicles when several vehicles try to attempt to use a single lane road.
If there is a case when all viewers are trying to stream data from the original point, then the server of origin plus its surrounding infrastructure network are choked, becoming a choking point and making the stream to slow down. But in case the main burden of delivery of stream is shifted to the CDN, then it eliminates the choke point.
Global delivery of content
Since the CDNs are all throughout the world, they can deliver data globally to the audience. It is good, especially with heavy content such as video. But the CDN is able to forward as well as serve content from one point on the network from the nearest CDN point of the audience instead of coming from the main server, which might be miles away.
RTT reduction and Latency
Using CDN to deliver content locally tends to reduce the latency on a live stream by views because it cuts down on the round trip time .
