So far, we have described the message system as it operates within our local network. A network is a group of machines that are connected to each other. You may wish to send messages outside our network to computers or hosts on other networks.
U.C. Berkeley is directly connected to a network called the Internet. The Internet is a collection of regional networks that support the TCP/IP networking protocol. Over 250,000 computers are connected to this network. U.C. Berkeley can indirectly access networks like BITNET through computers that serve as gateways between the Internet and that network. There are very few networks that we cannot access in some fashion.
Internet username@host.organization.domain Internet username@host.subdomain.organization.domain BITNET username@bitnethost.bitnetIf you don't know a network address, contact your correspondent (by phone or paper mail) and ask for a network address. You can send mail to network addresses on the Internet, BITNET and many other popular networks.
If someone wants to send you mail, they should use an address of the form:
username@hostname.EECS.berkeley.edu orwhere username is the username you use when you login to your account and hostname is the name of the computer you are on.
username@hostname.berkeley.edu
Network connections on the Internet and BITNET are reliable and do
not often cause problems. However, other networks (especially
networks like UUCP) can be unstable. This means that
sometimes your mail will not make it to another host or that it will
travel slowly. The more complicated the network connection, the
less likely it is that your message will reach its destination. If
you are experiencing a problem, you should address a
question to postmaster@berkeley.edu. Be sure to detail the
problem and provide any error messages you might have received from
the remote host.
The From: field produced by mh or mail may not always allow mailers on other hosts to reply correctly to your mail. Some remote hosts modify the address in the From: field in an attempt to ensure an accurate reply. If the From: field is changed incorrectly by a remote host, the address may be unusable.
If this is a problem for one of your correspondents, you can insert a field called Reply-to: that contains the appropriate reply address allowing users on other hosts to send you mail with less aggravation. If the other mailer does not automatically use the Reply-to: field, hopefully the other user may notice and try the return address listed there; mh will not alter explicitly stated Reply-to: fields.
You may also want to include a signature block that contains your name and network address. Signature blocks are a common way to end mail messages. To do this, create a file called ".signature" in your home directory and put your name and network address in it. This file will be appended to every mail message that you send out.