IT1451 -WEB TECHNOLOGY

1. What is the difference between node and host?

A node is any addressable device connected to a network whereas the host is a more specific descriptor that refers to a networked general-purpose computer rather than a single purpose device (such as a printer).

2. What is the purpose of routers?

Router operates like electronic postal workers that evaluate and forward packets

between networks.

3. Define protocol.

A protocol is a formal set of rules that must be followed in order to communicate.

4. Why are the protocols layered?

Layering protocols simplifies the task of communicating over the network and it

allows for reuse of layers that are not specific to a particular application.

5. Define encapsulation.

Placing the data inside a package of headers is known as encapsulation.

6. Define port.

A port is a logical channel to an application running on a host. ie., The applications running on the host machines are uniquely identified by port numbers.

7. What do you mean by well-known ports?

Port numbers can range from 1 to 65535; however ports 1 to 1023 are reserved.

These reserved ports are referred to as we1l-known ports because the Internet Assigned Numbers Authority publicly documents the applications that use them.

8. What is meant by Name Resolution?

Name Resolution is the process of mapping a hostname to its corresponding IP

Address.One way to translate a hostname to an IP address is to look it up in a simple text file.The second way is the domain name service, which is a distributed database containing all registered hostnames on the Internet and their IP addresses.

9. Define protocol tunneling.

Protocol tunneling is the process of encapsulating one protocol within another

protocol that operates on the same layer.

10. Define URI, URL, URN.

1. URI (Uniform Resource Identifier): It identifies an object on the Internet.

2. URL (Uniform Resource Locator): It is a specification for identifying an such as a file, newsgroup, CGI program or e-mail address by indicating the exact location on the internet.

3. URN (Uniform Resource Name): It is a method for referencing an object   without declaring the full path to the object.

11. What are the components of HTTP URL?

The components are host, an optional port, path, filename, and section and query string

12. Define URL encoding.

URL encoding involves replacing all unsafe and nonprintable characters with a

 Percent sign (%) followed by two hexadecimal digits corresponding to the character’s ASCII value.

13. Explain the various Specifics of SMTP Protocol?

 Operational Scenario.

 Command Semantics & Procedures

 Forwaring of Messages.

 Example of Forwarding

14. What is meant by Scripting Language?Explain any one of the Scripting Languages?

    Definition-To create Dynamic Web content.

        Eg:VB Script & Java Script

        Introduction about VB Script

        Functions of VB Script

       VB Script Execution Environment

        Embeding VB Script in to HTML.

        Objects & Events.

       Manipulating VB Script Variables with Operators.

        Functions & Procedures.

15. Explain the various methodologies by which you can retrieve data from Internet?

     Internet Search Engine

     Protocols used to retrieve the Data

     i)FTP –Concepts

     Commands &Semantics

     Anonymous FTP

     ii)TELNET

     Network Virtual Treminal

     Commands *Control Functions

     Negotiable Options

     iii)HTTP

     iv)TFTP