* You need to know the exact address of your recipient, and whether he's using this mailbox regularly. Many users have mailboxes that they use rarely or never. For example, don't try to send mail to my mailbox on Dow Jones/News Retrieval. I only use this service sporadically. Think of the easiest way for a recipient to respond before sending a message to him or her.
* You need to know how to rewrite the recipient's address to fit your system. For example, you may have to use a domain address to send through Internet, and a different form when sending through an X.400 network. (More about this later.)
* The recipient's mailbox system may be connected to a network that does not have a mail exchange agreement with your system's network(s). Sometimes, you can use a commercial mail relay service to get your message across (see chapter 9). Users of the Internet can send messages to recipients on the Dialcom network through the DASnet relay service.
* Sometimes, you need to know how to route a message through other systems to arrive at its destination. For example, a message sent from the Ulrik computer in Oslo must be routed through a center in London to get to Dominique Christian on the Difer system in Paris (France),
Internet ———— is the name of a computer network (here called "INTERNET"), and a term used of a global web of systems and networks that can exchange mail with each other (here called "Internet"). INTERNET is a very large network that has grown out of ARPANET, MILNET, and other American networks for research and education. This core network has many gateways to other systems, and it's when we include these systems and their connections that we call it the Internet. Others call it WorldNet or the Matrix. Internet users can exchange mail with users on networks like EUnet, JANET, Uninett, BITNET, UUCP, CompuServe, MCI Mail, EcoNet, PeaceNet, ConflicNet, GreenNet, Web, Pegasus, AppleLink, Alternex, Nicarao, FredsNaetet, UUNET, PSI, Usenet, FidoNet and many others. We therefore say that these networks are also "on the Internet." If you have access to the Internet, you can send email to users of online services all over the world. You can send to people using Bergen By Byte and Telemax in Norway, TWICS in Tokyo, and Colnet in Buenos Aires. Now is the time to take a closer look at the art of addressing mail through the Internet.
Domain name addressing ——————————— On the Internet, the general form of a person's email address is:
user-name@somewhere.domain
My main, international Internet mailbox address is:
opresno@extern.uio.no
You read the address from left to right. First, the local name of the mailbox (my name abbreviated). Next, the name of the mailbox system or another identification code (in this case EXTERN, to show that I have no affiliation with the University), the name of the institution or company (here UIO or "Universitetet i Oslo"), and finally the country (NO for Norway). People have sent mail to my mailbox from New Zealand, Zimbabwe, Guatemala, Peru, India, China, Greece, Iceland, and Armenia using this address. Some users must send their messages through a gateway to the Internet. In these cases, the address may have to be changed to reflect this: Users of AppleLink use opresno@extern.uio.no@INTERNET# . Those on JANET use opresno%extern.uio.no@eanrelay.ac.uk. On SprintMail, use ("RFC-822": <opresno(a)extern.uio.no>, SITE:INTERNET) . CompuServe subscribers use >INTERNET:opresno@extern.uio.no . The core of these address formats is "opresno@extern.uio.no", in one way or the other. We call this basic addressing format a Domain Naming System. "EXTERN.UIO.NO" is a domain. The domain may also contain reference to the name of a company or an organization, like in twics.co.jp, compuserve.com, or IGC.ORG. The CO, COM, and ORG codes identify TWICS, CompuServe and IGC as companies/organizations. To send mail from the Internet to my CompuServe mailbox, use: