k's Space计算机网络
互联网协议（五层模型）
- 应用层
- 传输层
- 网络层
- 链接层
- 实体层
HTTP协议
HTTP/0.9
发送
http
GET /index.html接收
http
<html>
<body>Hello World</body>
</html>只能接收HTML格式
HTTP/1.0
发送
http
GET / HTTP/1.0
User-Agent: Mozilla/5.0 (Macintoch: Intel Mac OS X 10_10_5)
Accept: */*接收
http
HTTP/1.0 200 OK
Content-Type: text/plain
Content-Length: 137582
Expires: <...>
Server: Apache 0.84
\r\n
<html>
<body>Hello World</body>
</html>\r\n代表空行
Content-Type (MIME type)
- text/plain
- text/html
- text/css
- image/jpeg
- image/png
- image/svg+xml
- audio/mp4
- video/mp4
- application/javascript
- application/pdf
- application/zip
- application/atom+xml
HTTP1.0只能连接一个请求，为了解决这个问题，引入HTTP1.1。
二者最大的区别在于HTTP1.1引入了持久连接，默认
Connection: keep-alive
HTTP1.1
特性
持久连接
管道机制
Content-Length字段
分块传输编码
Transfer-Encoding: chunkedhttpHTTP/1.1 200 OK Content-Type: text/plain Transfer-Encoding: chunked 25 This is the data in the first chunk 1C and this is the second one 3 con 8 sequence 0
HTTP/2
一个彻底的二进制协议 头信息和数据体都是二进制，统称为“帧”