1. carried by the internet engineering task force(ietf)

1. Introduction                         HTTP stands for Hyper Text Transfer Protocol. HTTP works at application layer, transfering data for world wide web(www). Thisprotocol was devloped initially by Tim-Berners-Lee at CERN in 1989. Standardsdevelopment of HTTP was further carried by the Internet Engineering TaskForce(IETF) and the World Wide Web Consortium(W3C).

HTTP is designed to allow elements insidenetwork to enable communications between clients and servers. A web browser isan example of a client, this list also include the indexing software used bysearch provide, mobile apps, voice browsers, and other software that accesses, consumes, or displays web content. 2. HistoryThe term hypertext was coined by Ted Nelson in1965 in the Xanadu Project, which was in turn inspired by Vannevar Bush’s 1930svision of the microfilm-based information retrieval and management” memex” system described in his 1945 essay “ As We MayThink”. Tim Berners-Lee and his team at CERNare credited with inventing theoriginal HTTP along with HTML and the associated technology for a web serverand a text-based web browser.

Year    HTTPVersion1991    0. 91996    1. 01997    1.

12015    2. 0The first documented version of HTTP was HTTPV0. 9 in 1991. They wanted to improve protocol’s efficency by extendingoperations, richer meta-information, tied with a security protocol .

2. 1 HTTP V0. 9 The Hypertext Transfer protocol originally asimplemented by the World Wide Web initaitive software in the prototypereleased.

This was HTTP 0. 9 which was subset of the full HTTP protocol. It usedTCP-IP link as used in old traditional styled internet.

It mainly has 4 steps, Connection, Request, responce, disconnect:  Connection            Theclient makes a TCP-IP connection to the domain or IP, at the port number givenin     the address. The port number forHTTP is 80 by default. The server accepts the connection. Request            Theclient sends a request of a line of ASCII characters       terminated by a CR LF pair. A well-behaved server will notrequire the carriage return character.

This request             consists of the word “ GET”, a space, thedocument address. Response            Theresponse, in ASCII to a simple GET request is a message in hypertext mark-up         language (HTML ). Error are supplied in human readable text in HTML. There is noway       to distinguish an error responsefrom a satisfactory response except for the content          of the   text.

Disconnection            Theconnection is disconnected by the server when the whole document has been           transferred. Thus, the server do notneed to store any information about the request after disconnection. For the newdocument, client has to repeat the whole process. StatusCodes: The values of the numeric status code to HTTPrequests are as follows.

The data sections of messages Error, Forward andredirection responses may be used to contain human-readable diagnosticinformation. Success (2xx)These codes indicate success. The body sectionif present is the object returned by the request. It is a MIME format object. It is in MIME format, and may only be in text/plain, text/html or one fo theformats specified as acceptable in the request.

?    OK (200) : The request wasfulfilled.?    CREATED(201): This occurs when the webpage is successfully created.?     Accepted (202): This occurs when therequest has been accepted. The further processing takes place afterwards.?    PartialInformation (203) : This states that the information provided is not complete set ofmetadata.?    No Response(204): This indicates that server has got request butthere is nothing to return the client.  Error (4xx, 5xx)The 4xx codes are for cases in which theclient have erred, and the 5xx codes for the cases which the server has erred. ?    Bad request (400) : The client request is with bad/wrong syntax to be satisfied.

?    Unauthorized(401) : The parameter passed for authentication have failed to do so.?    PaymentRequired(402) : The parameter to this message gives aspecification of charging schemes acceptable.?    Forbidden(403) :  Therequest is for something forbidden. ?    Not found(404) : The server has not found anything matchingURI.?    InternalError (500) : The server encountered an unexpectedcondition.?    Notimplemented (501) : The server does not support thefacility.

?    Servicetemporarily overloaded (502) : The server cannotprocess the request due to a high load.?    Gatewaytimeout (503) : This is equivalent to Internal Error500, the server is waiting for some other service for reply which the serverdid not receive within the timeout limit. Redirection 3xxThecodes in this section indicate action to be taken by the client in order tofulfill the request.

?    Moved (301): The datarequested has been assigned a new URI. Browsers should automatically relink to the new reference.?    Found (302): The datarequested actually resides under a different URL, however, the redirection maybe altered on occasion as for “ Forward”.?    Not Modified(304) : Ifthe client has done a conditional GET and access is allowed, but the documenthas not been modified since the date and time specified in If-Modified-Since field, the server respondswith a 304 status code and does not send the document body to the client.

2. 2 HTTP V1. 0 HTTP V1. 0 is evolved from the original HTTPV0.

9. The process leading to HTTP V1. 0 involved significant debate andexperimentation, but never result to a formal specification.

HTTP V1. 0 usesmany of the constructs defined for MIME. HTTP allows for different use ofInternet Media Types than is typically found in Internet mail. HTTP is also usedas a protocol for communication between user agents and proxies/gateways.