University Department of Management Science

Sub Campus Osmanabad

Seminar Topic

Hypertext Transfer Protocol

Guided By

Mr. Varunraj Kalse

Conducted By

Mr. Vikrant S. PotdarM.C.A. Sem III

Introduction

Introduction to Hypertext Transfer Protocol(HTTP)

HTTP Communication

Request Headers

Request Methods

Responses

Status Codes

Error Status Codes

Introduction to Hypertext Transfer Protocol

• It is a method of transferring information over world wide web.

• It provides a way to publish HTML pages.

• World wide web consortium and Internet Engineering Task Force(IETF) develops this protocol.

• In these days we use Http1.1 version.

• It is request / response protocol between clients and servers.

• Web browsers are called user agents and specified servers are called as origin servers.

• Http clients initiate request by establishing Transmission Control Protocolconnection to the remote host.

• On receiving request servers sends a status line such as Http:/1.1 200to the clients.

HTTP Communication

• Client sends request to server then new TCP/IP connections are open using Domain name, IP address, Port number.

• If port number is not defined then it take default port number 80.

• Then client places the request by issuing the word “GET”.

• Then Client must wait for reply from server.

Server

Client

Request Headers

• Request line such as GET/images/logo.gif http/1.1 which requests image from the image directory.

• Headers are in the format of Accept – language : en or an empty line or an optional massage body.

•The request line and headers must all end with CRLF(Carriage Return followed by Line Feed).

•Some headers are optional while some required by http:/1.1 protocol.

Request Methods

1. HEADUseful for retrieving meta information written in response

header.

2. GETRequest a representation of specified resource.

3. POSTSubmit a data which is processed.

4. PUTIt is useful for uploading the resources.

5. DELETEIt is useful for deleting the resources.

6. TRACEIt is useful for getting echoes of send requests. Generally it is

used in search engines.

Responses

It generally contains the information about server like

http:/1.1 200 okdate : (date with time)server: apache/1.3.27( Unix )last modified: (date & time)accept range : bytescontent length : size of resourceconnection : (State of connection open/close)content type : text/html

Status Codes

1. The first line of http response is known as status line.

2. Status line includes numeric status code such as 404.

3. Status also includes textual reason phrase such as “not found”.

4. When user agent encounters the code it uses Custom status code.

Error Status Codes

1. If status code indicate problem then user agent shows the reason phrase and the nature of problem.

2. The above described code is called as Error Status Code.

Question and Answer