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:
Date: Mon, 3 Jan 83 08:33:47 MST
Subject: network news message
NFrom: derek@sask.UUCP (Derek Andrew)
NSubject: necessary test
NDate: Mon, 3 Jan 83 00:59:15 MST
NThis really is a test. If anyone out there more than 6
Nhops away would kindly confirm this note I would
Nappreciate it. We suspect that our news postings
Nare not getting out into the world.
Using mail solves the spooling problem, since mail must always be spooled if the destination host is down. However, it adds more overhead to the transmission process (to encapsulate and extract the message) and makes it harder for software to give different priorities to news and mail.
RFC1036: [Source:"RFC-1036"] [Last Changed:December 1987] [Copyright: 1987 M. Horton, R. Adams]
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