What Is TCT/IP Protocol?
- HTTP is built on the TCP / IP protocol and the default port number is 80
- HTTP is a connectionless stateless of
- HTTP packets
- Request message
The HTTP protocol is transmitted in ASCII code and establishes an application layer specification over the TCP / IP protocol. The specification divides the HTTP request into three parts: the status line, the request header, and the message body. Similar to the following:
<method> <request-URL> <version>
HTTP defines different ways to interact with the server, there are four basic methods, namely GET, POST, PUT, and DELETE. Add, change, delete, and delete operations on the network, and the HTTP GET, POST, PUT, and DELETE on operations.
1.GET is used for information acquisition and should be safe and idempotent.
The so-called safe means that the operation is used to obtain information instead of modifying information. In other words, GET requests should not generally produce side effects. That is to say, it will only obtain obtainable resource information, just like a database query, it will not be modified, add data, will not affect the state of the resource can get by proxysite.
Impotence means that multiple requests to the same URL should return the same result.
Example of a GET request message:
GET / books /? Sex = man & name = Professional HTTP / 1.1
User-Agent: Mozilla / 5.0 (Windows; U; Windows NT 5.1; en-US; rv: 1.7.6)
Gecko / 20050225 Firefox / 1.0.1
- The POST indicates that the request to change resources on the server may be modified.
- POST / HTTP / 1.1
- Host: www.example.com
- User-Agent: Mozilla / 5.0 (Windows; Windows NT 5.1; en-US; rv: 1.7.6)
- Gecko / 20050225 Firefox / 1.0.1
- Content-Type: application / x-www-form-urlencoded
- Content-Length: 40
- Connection: Keep-Alive
- Sex = man & name = Professional
The amount of data that GET can submit is limited by the length of the URL, and the HTTP protocol specification does not restrict the length of the URL. This limit is limited by the specific browser and server
Theoretically speaking, POST is not limited in size, and the HTTP protocol specification has no size limit. For security reasons, server software will impose certain restrictions when it is implemented.