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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP Interactive and Remote Application Protocols

Other Berkeley Remote ("r") Commands (rcp, ruptime, rwho) 1 2 3 TCP/IP Administration and Troubleshooting Utilities and Protocols

The primary advantage that electronic mail offers over conventional mail is speed. Instead of having to wait for days or weeks for a message to be delivered, it usually arrives in minutes or even seconds. This makes electronic mail far more useful than the regular postal service for most types of information transfer. There are some cases, however, where speed of delivery is not sufficient to make electronic mail an ideal mechanism for communication. One such case is where a dialog is required between two parties.

Consider that even though electronic mail may be delivered very quickly, it uses a decoupled model of communication. When person A sends an e-mail to person B, the message may show up in B’s inbox in a matter of seconds, but B may not in fact be around to read it at the time it arrives. B might not see the message until hours later; he would then send a response to A, who in turn might not see it for a while. If the subject they are discussing requires several dozen iterations of this sort, it could take a very long time before the exchange is completed.

In the real world, of course, most of us would never use mail for such a conversation, preferring instead that high-tech communication device that we call… the telephone. J Many people using computers realized that it would be useful to have a way for two or more people to interactively discuss issues in a manner similar to a telephone conversation. In the online world, this is commonly called chatting, and one of the first and most important application protocols designed to implement it in TCP/IP was the Internet Relay Chat Protocol (IRC).

Prior to the widespread use of the Internet, people with computers would often communicate by dialing in to a bulletin board system (BBS) or other proprietary service. IRC was originally created by a gentleman from Finland named Jarkko Oikarinen, based on his experience with chat applications on BBSes. He wrote the first client and server software in 1988; the protocol was later formally defined in RFC 1459, Internet Relay Chat Protocol, published May 1993. In April 2000, the IRC standard was revised and enhanced with several new extended capabilities, and published as a set of four smaller documents: RFCs 2810 through 2813. Each of these focuses on one particular area of IRC functionality.

Other Berkeley Remote ("r") Commands (rcp, ruptime, rwho) 1 2 3 TCP/IP Administration and Troubleshooting Utilities and Protocols