resting on top of several existing physical networks. These
networks include, but are not limited to, UUCP, the Internet, an
Ethernet, the BLICN network, an NSC Hyperchannel, and a BERKNET.
What is important is that two neighboring systems on USENET have
some method to get a new message, in the format listed here, from
one system to the other, and once on the receiving system, processed
by the netnews software on that system. (On UNIX systems, this
usually means the rnews program being run with the message on the
standard input. )
It is not a requirement that USENET hosts have mail systems capable
of understanding the Internet mail syntax, but it is strongly
recommended. Since "From", "Reply-To", and "Sender" lines use the
Internet syntax, replies will be difficult or impossible without an
Internet mailer. A host without an Internet mailer can attempt to
use the "Path" header line for replies, but this field is not
guaranteed to be a working path for replies. In any event, any host
generating or forwarding news messages must have an Internet address
that allows them to receive mail from hosts with Internet mailers,
and they must include their Internet address on their From line.
4.1. Remote Execution
Some networks permit direct remote command execution. On these
networks, news may be forwarded by spooling the rnews command with
the message on the standard input. For example, if the remote
system is called remote, news would be sent over a UUCP link
with the command:
uux - remote!rnews
and on a Berknet:
net -mremote rnews
RFC 1036 Standard for USENET Messages December 1987
It is important that the message be sent via a reliable mechanism,
normally involving the possibility of spooling, rather than direct
real-time remote execution. This is because, if the remote system
is down, a direct execution command will fail, and the message will
never be delivered. If the message is spooled, it will eventually
be delivered when both systems are up.
4.2. Transfer by Mail
On some systems, direct remote spooled execution is not possible.
However, most systems support electronic mail, and a news message
can be sent as mail. One approach is to send a mail message which
is identical to the news message: the mail headers are the news
headers, and the mail body is the news body. By convention, this
mail is sent to the user newsmail on the remote machine.
One problem with this method is that it may not be possible to
convince the mail system that the "From" line of the message is
valid, since the mail message was generated by a program on a
system different from the source of the news message. Another
problem is that error messages caused by the mail transmission
would be sent to the originator of the news message, who has no
control over news transmission between two cooperating hosts
and does not know whom to contact. Transmission error messages
should be directed to a responsible contact person on the
sending machine.
A solution to this problem is to encapsulate the news message into a
mail message, such that the entire message (headers and body) are
part of the body of the mail message. The convention here is that
such mail is sent to user rnews on the remote system. A mail
message body is generated by prepending the letter N to each line of
the news message, and then attaching whatever mail headers are
convenient to generate. The N's are attached to prevent any special
lines in the news message from interfering with mail transmission,
and to prevent any extra lines inserted by the mailer (headers,
blank lines, etc.) from becoming part of the news message. A
program on the receiving machine receives mail to rnews, extracting
the message itself and invoking the rnews program. An example in
this format might look like this:
RFC 1036 Standard for USENET Messages December 1987
=9= |