Theory-74:-TCP /IP /FTP /Telnet

Protocols:

A protocol is a set of rules and guidelines for communicating data. A protocol is a standard used to define a method of exchanging data over a computer network such as local area network, Internet, Intranet, etc. Each protocol has its own method of how data is formatted when sent and what to do with it once received, how that data is compressed or how to check for errors in data.

Network protocols serve these basic functions:

• Address data to the correct recipient(s)
• Physically transmit data from source to destination, with security protection if needed
• Receive messages and send responses appropriately.

 

TCP/IP:

Short for Transmission Control Protocol/Internet Protocol, TCP/IP is a set of rules (protocols) governing communications among all computers on the Internet. More specifically, TCP/IP dictates how information should be packaged (turned into bundles of information called packets), sent, and received, as well as how to get to its destination. TCP/IP was developed in 1978.

How does TCP/IP work?

As the name implies, TCP/IP is a combination of two separate protocols: Transmission Control Protocol (TCP) and Internet Protocol (IP). The Internet Protocol standard dictates the logistics of packets sent out over networks; it tells packets where to go and how to get there. IP has a method that lets any computer on the Internet forward a packet to another computer that is one or more intervals closer to the packet's recipient. You can think of it like workers in a line passing boulders from a quarry to a mining cart. The Transmission Control Protocol is responsible for ensuring the reliable transmission of data across Internet-connected networks. TCP checks packets for errors and submits requests for re-transmissions if any are found.

(FTP)File Transfer Protocol:

File Transfer Protocol (FTP) is a client/server protocol used for transferring files to or exchanging files with a host computer. It may be authenticated with user names and passwords. Anonymous FTP allows users to access files, programs and other data from the Internet without the need for a user ID or password. Web sites are sometimes designed to allow users to use 'anonymous' or 'guest' as a user ID and an email address for a password. What File Transfer Protocol can do:

• Transfer files between computers.
•  Create directories.
•  Remove directories.
•  List files.

 

Telnet :

Telnet (short for TErminal NETwork) is a network protocol used to provide a command line interface for communicating with a device.

Telnet is used most often for remote management but also sometimes for the initial setup for some devices, especially network hardware like switches, access points, etc. Managing files on a website is also something Telnet is sometimes used for. Telnet is sometimes written in uppercase as TELNET and may also be misspelled as Telenet.

The Telnet Protocol:

The Telnet protocol is designed to provide a bi-directional, eight-bit byte oriented communications facility to allow for aa standard method of interfacing terminal devices and processes.

• Telnet is not the same thing as other TCP/IP protocols like HTTP, which just let you transfer files to and from a server. Instead, the Telnet protocol has you log on to a server as if you were an actual user, granting you direct control and all the same rights to files and applications as the user that you're logged in as.