on the Internet, quietly grow a time for people of the service network, it is like an invisible courier, will deliver a wide variety of content to the user, this is a content distribution network (CDN Content, Distribute Network).
CDN basic concepts and background
Content Network Distribute, literally translated into content distribution network, or someone wrote Content Delivery Network, content delivery network.
big talk about the Internet, is the broad sense of the Internet, consisting of two layers: one layer is represented by TCP/IP network layer (also the concept of narrow sense of the Internet); another layer is the world wide web WWW as the representative of the application layer. At present, there is a common misunderstanding, is the Internet and the world wide web Hunzuoyitan. Recognize the nature of the Internet, identify the difference between the Internet and the world wide web, is the key to understanding the entire Internet economy and the foundation, but also the basis of understanding CDN.
to TCP/IP as the core of the narrow sense of the Internet (Internet), in fact, is the lower level of the broad sense of the Internet, is the basis of the network, in general, is the TCP/IP network. The main role of this layer is through the interconnection between computers, a variety of information packets to the very low cost of transmission, commonly known as "pipeline", all the information and content in this pipeline for transmission. The design concept of the Internet is that the network is neutral and uncontrolled, and no one has the right to decide. The network is irrelevant to the application. This design concept from the beginning of the birth of the Internet has never been shaken, any attempt to optimize the Internet for some (type) content of the final results are not ideal. Therefore, we can think that the Internet will not attempt to optimize the transmission of any content.
to the world wide web WWW as the representative of the application layer, the upper layer of the broad internet. This layer includes the flow and application of many types, mail, software, online video, games, e-commerce, mobile applications, all SP (Service Provider, service provider) are provided by these users tangible, they enrich and facilitate the people’s lives, which we often said the Internet business and economic information.
Development history of
CDN is used for service on the Internet, it is accompanied by the development of the Internet and gradually grow, development in the process of its development, the ups and downs of peaks and valleys are basically consistent with the entire Internet, figure 1-4 is the historical development of the CDN curve, we take a review of the development history of CDN. >