MULTIMEDIA

1. What are the sequences of steps for each HTTP request from a client to the server?

1. Making the connection

2. Making a request

3. The response

4. Closing the connection

2. Write a note on Internet Information Server (IIS)?

Microsoft’s Web server that runs on Windows NT platforms, In fact, IIS comes

Bundled with Windows NT 4.0. Because IIS is tightly integrated with the operating system, it is relatively easy to administer. However, currently IIS is available only for the Windows NT platform, whereas Netscape’s Web servers run on all major platforms, including Windows NT platform, OS/2 and UNIX.

3. Explain about HTTP Connection?

It is a communication channel between web browser and web server. It begins on the

Client side with the browser sending a request to the web server for a document.

Request Header Fields are

1. From

2. Reference

3. If_modified_since

4. Pragma

5. User Agent

4. What is meant by Stateless Connection?

When a web server receives a HTTP request from a web browser it evaluates the

request and returns the requested document, if it exists, and then breaks the HTTP connection. This document is preceded by the response header, which has details about how to display the document that will be sent by the server. Each time a request is made to the server, it is as if there was no prior connection and each request can yield only a single document. This is known as Stateless Connection.

5. Write a note on Environment variables.

In CGI, the server prepares the environment variables before it launches the CGI

Script. These represent the current state of the server that is asking for the information. The environment variables are not set from the command line but are created on the fly, and lasts only until that particular script is finished. Each script gets its own unique set of variables and multiple scripts can be executed at once, each in its own environment.

6. What are STDIN and STDOUT?

These are mnemonics for standard input and standard output, two predefined stream

/ file handles. Each process already inherits these two handles already open. From the script’s point of view, STDIN is what comes from the browser via the server when the post method is used, and the STDOUT is where it writes its output back to the browser. The script picks up the environment variables and reads STDIN as appropriate. It then does whatever it was designed to do and writes its output to STDOUT