Web Technology

Pawan P. Kolhe. MBA IT (Iyr)- B PRN NO:060341067

Topics Covered In Presentation •Typical Web Usage •Component of Web Usage HTML XML URL HTTP -Client side -Server side Proxy Server

Typical Web Usage

HTML

XML

HTTP

HTTP Methods

Proxies

Client Side Client-side dynamic content is generated on the client's computer. The Web server retrieves the page and sends it as is. The Web browser then processes the code embedded in the page (normally JavaScript) and displays the page to the user. The inner HTML property (or write command) can illustrate the "Client-side dynamic page" generation: 2 distinct pages, A and B, can be regenerated (by an "event response dynamic") as document. Inner HTML = A and document. Inner HTML = B; or "on load dynamic" by document. Write (A) and document write (B). The problems with client-side dynamic pages are: 1.Some browsers do not support the language or they do not support all aspects (like write command and inner HTML property) and of the language. 2.The information cannot be stored anywhere but the user's computer, so it cannot really be used for statistics gathering. 3.Search engines are not able to run client-side languages and cannot crawl links generated by them. 4.Some users have scripting languages disabled in their browsers due to possible security threats.

Server Side Server-side dynamic content is a little bit more complicated. 1.The browser sends an HTTP request. 2.The server retrieves the requested script or program. 3.The server executes the script or program which typically outputs an HTML Web page. The program usually obtains input from the query string or standard input which may have been obtained from a submitted Web form. 4.The server sends the HTML output to the client's browser. 5.Server-side has many possibilities for dynamic content, but the use of it can be a strain on low-end, high-traffic, machines. Some Web sites use the Robots Exclusion Standard to keep Web crawlers from accessing dynamic pages for this reason. If not properly secured, server-side scripts could be exploited to gain access to a machine. 6.Server-side has many possibilities for dynamic content, but the use of it can be a strain on low-end, high-traffic, machines. 7.If not properly secured, server-side scripts could be exploited to gain access to a machine.

Proxies

Summary Web Technology underlies web services - HTTP is the basic transport