TCP/ IP Application Protocols

DNS stands for Domain Name System, which is a protocol used to translate domain names into IP addresses. When we type a domain name into a web browser, the DNS system is responsible for finding the corresponding IP address of that domain. This is necessary because computers communicate using IP addresses, but domain names are more user-friendly. DNS servers store a database of domain names and their corresponding IP addresses, allowing users to access websites and other resources on the internet by simply typing in the domain name.

SMTP stands for Simple Mail Transfer Protocol. It is a protocol used for sending and receiving email messages over the internet. SMTP provides messaging services over TCP/IP, which is the standard communication protocol used on the internet. It supports most internet email programs, allowing users to send and receive emails using their preferred email client. SMTP is responsible for the transmission of email messages from the sender's email client to the recipient's email server. It ensures that the email is delivered to the correct destination and handles any necessary routing and delivery processes.

FTP stands for File Transfer Protocol. It is a set of rules that govern how files are transferred between computers on a network. FTP allows multiple simultaneous connections to remote file systems, enabling users to upload, download, and manage files on a remote server. It is commonly used for website maintenance, software distribution, and file sharing. SMTP (Simple Mail Transfer Protocol) is used for sending emails, HTTP (Hypertext Transfer Protocol) is used for web browsing, and DNS (Domain Name System) is used for translating domain names into IP addresses.

Telnet is the correct answer because it is an application that allows users to remotely access, control, and troubleshoot computers and network devices. It provides a command-line interface to interact with remote systems, making it useful for tasks such as remote administration and remote login. FTP is a file transfer protocol, SMTP is a protocol for email transmission, and DNS is a system for translating domain names into IP addresses.

HTML stands for Hypertext Markup Language and is a page description language used to create the structure and layout of web pages. It is not a programming language, but rather a markup language that uses tags to define elements like headings, paragraphs, links, images, and more. HTML is interpreted by web browsers to render the content and determine how the page should look and behave. It is not related to Telnet or SMTP, which are network protocols, or HTTP, which is a communication protocol.

HTTP (Hypertext Transfer Protocol) is the correct answer because it is the protocol that governs how files such as text, graphics, audio, and video are exchanged on the Internet or World Wide Web. It is the foundation of data communication for the World Wide Web and allows for the retrieval and display of web pages. FTP (File Transfer Protocol) is another protocol used for file exchange, but it is primarily used for uploading and downloading files, rather than the exchange of web content. HTML (Hypertext Markup Language) is a markup language used for creating web pages, but it is not responsible for the exchange of files on the Internet.