HTTP response Messages

The HTTP response is also made up of three parts: the status line, the message header, and the response body.

Where http-version represents the version of the server HTTP protocol, Status-code represents the response status code sent back by the server, and Reason-phrase represents a textual description of the status code. The status code consists of three digits, the first number defines the category of the response, and there are five possible values.

• 1XX: Indicates that the request has been received and continues processing.
• 2XX: Success-Indicates that the request has been successfully received, understood, accepted.
• 3XX: Redirect--further action is required to complete the request.
• 4XX: Client Error--the request has a syntax error or the request is not implemented.
• 5XX: Server-side error-the server failed to implement a legitimate request.

A description of the common status code and status is described below.

• OK: Client request succeeded.
• Bad Request: Client requests have syntax errors and cannot be understood by the server.
• 401 Unauthorized: Request is not authorized, this status code must be used with the Www-authenticate header domain.
• 403 Forbidden: The server receives the request but refuses to provide the service.
• 404 Not Found: The request resource does not exist, for example: The wrong URL was entered.
• Internal Server error: Unexpected errors occurred on the server.
• 503 Server Unavailable: The server is currently unable to process client requests and may return to normal after a period of time, for example: http/1.1 OK (CRLF).

HTTP response Messages