2015/4/25~ deep understanding of the Web request process

1, from the C/s architecture to B/s architecture two points of benefit:

1, the client unified use of the browser, the browser's interactive features make it very easy for users to use it, and shielding the different service providers to provide users with the difference of service.

2, the service side based on a unified HTTP protocol, using a unified HTTP protocol, so that service providers simplify, standardize the development model, greatly reducing the development costs, the server and framework can be used directly, without their own development, to promote the emergence of more services.

2, with the traditional C/s architecture using long-link interaction data, HTTP uses a non-state short-link communication mode, each request to complete a data interaction, usually also corresponds to a business logic.

3, a request process:

1, the user enters a URL in the browser, requests DNS to resolve the domain name to the corresponding IP address

2, through the IP address to the Internet to find the corresponding server

3, the server may have more than one, the load Balancer device distributes the request to different servers

4, get the return data, the data may be stored in the distributed cache, the static file, or the database

5, the returned data if it is static resources, such as CSS files, JS files, pictures, etc., will also initiate additional HTTP requests. These files may be on the CDN server, and the CND server will process these requests.

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Summary: No matter how the architecture changes, some immutable principles need to be adhered to. 1, so resources have to be represented by a URL, url is a Uniform Resource Locator, 2, must be based on HTTP and server interaction; 3. The data must be displayed in the browser.

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2015/4/25~ deep understanding of the Web request process