HTTP protocol performance-related technical essentials

1.http Protocol Introduction

HTTP is a request/response protocol that transmits data based on the TCP protocol.

HTTPS is a combination of the HTTP protocol and the condom layer (SSL), the security-enhanced version of HTTP.

The HTTP request consists of three parts: the request line, the message header, and the request body (optional).

Request line e.g.

get/http/1.1

Request Line Format:

1) Method (Request method) 2) Request-uri (Uniform Resource Identifier) 3) Http-version (HTTP protocol version) 4) CRLF (carriage return or newline)

Request Method:

Get: Request to get the resources identified by Request-uri Common

Post: Append new data to the resource identified by Request-uri common

HEAD: Request for a response message header for the resource identified by Request-uri

PUT: The requesting server stores a resource and uses Request-uri as its identity

Delete: Request Server Delete Request-uri The resource that is identified is commonly used

TRACE: Requests the server to echo received request information, primarily for testing or diagnostics

CONNECT: Keep Future use

Options: Request performance of the query server or query for resource-related options and requirements

The HTTP response consists of three parts: the status line, the message header, the response body

Status Line e.g.

http/1.1 OK

Status code:

1**: Indication information-Indicates that the request has been received and continues processing

2**: Success-Indicates that the request has been successfully received, understood, accepted

3**: Redirect--further action is required to complete the request

4**: Client Error--Request syntax error or request not implemented

5**: Server-side error-the server failed to implement a legitimate request

Common Status Codes:

$ OK//client request succeeded

Requests Bad//client request syntax error, cannot be understood by the server

401 Unauthorized//request unauthorized, this status code must be used with the Www-authenticate header field

403 Forbidden//server receives request, but refuses to provide service

404 Not Found//request resource does not exist, e.g. the wrong URL was entered

Internal Server error//server unexpected errors

503 Server Unavailable//server is currently unable to process client requests and may return to normal after some time

HTTP protocol performance-related technical essentials