Content Delivery Networks¶
The vast majority of today’s Internet traffic is media files (often video or audio) being sent from a single source (the Content Provider) to many thousands or even millions of destinations (the Content Consumers). CDNs are the technology that make that one-to-many distribution efficient. A CDN is a distributed system of servers for delivering content over HTTP(S). These servers are deployed in multiple locations with the goal of optimizing the delivery of content to the end users, while minimizing the traffic on the network. A CDN typically consists of the following:
- Cache Servers
- The cache server is a server that both proxies the requests and caches the results for reuse. Traffic Control uses Apache Traffic Server to provide cache servers.
- Content Router
- A content router ensures that the end user is connected to the optimal cache server for the location of the end user and content availability. Traffic Control uses Traffic Router as a content router.
- Health Protocol
- The Health Protocol monitors the usage of the cache servers and tenants in the CDN.
- Configuration Management System
- In many cases a CDN encompasses hundreds or even thousands of servers across a large geographic area. In such cases, manual configuration of servers becomes impractical, and so a central authority on configuration is used to automate the tasks as much as possible. Traffic Ops is the Traffic Control configuration management system, which is interacted with via Traffic Portal.
- Log File Analysis System
- Statistics and analysis are extremely important to the management and administration of a CDN. Transaction logs and usage statistics for a Traffic Control CDN are gathered into Traffic Stats.