Finctionality of Internet

Protocol

A protocol is a standard set of rules that governs how computers communicate with each other. Protocols describe both the format that a message must take and the way in which messages are exchanged between computers.

Different types of computers are able to communicate with each other - in spite of their differences - when they agree to use a protocol that offers a standard format and method for communication. Some of the protocols used on the Internet are TCP/IP, SMTP, FTP, HTTP, and NNTP.

A protocol is a standard set of rules that determines how computers communicate with each other across networks. A network is two or more computers that are physically connected to each other and able to share information.

When computers communicate with one another, they exchange a series of messages. To understand and act on these messages, computers must agree on what a message means.

Examples of messages include establishing a connection to a remote machine; sending or receiving e-mail; and transferring files and data.

A protocol describes:

• the format that a message must take, and

• the way in which computers must exchange a message

within the context of a particular activity, such as sending messages across networks, exchanging e-mail, establishing remote connections, or transferring files.

Think of an electronic mail message. Both the format of the electronic mail message and the way that it is transmitted across the network are described and governed by a protocol.

Protocols ensure that electronic mail messages are correctly formatted and transmitted from the originating computer to the destination computer. A comparison can be made to the rules that govern how letters are handled by the post office:

There are different protocols for different types of network services. For example, the Internet is based on the TCP/IP suite, or family, of protocols. Some of the protocols used on the Internet are:

• Simple Mail Transfer Protocol (SMTP) - to send and receive electronic mail

File Transfer Protocol (FTP) - to transfer files between computers

Hypertext Transfer Protocol (HTTP) - to transmit information on the World Wide Web

Network News Transfer Protocol (NNTP) - to transmit network news

Protocols enable different types of computers (Macintosh, PCs, UNIX, VMS, etc.) to communicate in spite of their differences. This is because they describe a standard format and method for communicating.

A very simple comparison can be made to Morse Code:

• People using Morse Code agree that a given combination of dots and dashes will always have the same meaning.

Someone who speaks only Russian and someone who speaks only Greek can exchange messages using Morse Code because they agree on the format and method for exchanging messages.