these  networks,  news  may  be  forwarded by spooling the
rnews command with the article 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".
It is important that the article be sent  via  a  reliable
mechansim, 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  article  will   never   be
delivered.   If the article 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 article 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.



                          - 14 -
 


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 article.  Another  problem  is  that  error  messages
caused  by  the  mail  transmission  would  be sent to the
originator of the news article, who has  no  control  over
news  transmission  between two cooperating hosts and does
not know who  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
article  into a mail message, such that the entire article
(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 article,  and  then  attaching  whatever  mail
headers  are convenient to generate.  The N's are attached
to prevent any special lines  in  the  news  article  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 article.  A program
on the  receiving  machine  receives  mail  to    "rnews",
extracting  the  article itself and invoking the   "rnews" 
program.  An example in this format might look like this:

     Date: Monday, 3-Jan-83 08:33:47 MST
     From: news@cbosgd.UUCP
     Subject: network news article
     To: rnews@npois.UUCP

     NRelay-Version: B 2.10  2/13/83 cbosgd.UUCP
     NPosting-Version: B 2.9 6/21/82 sask.UUCP
     NPath: cbosgd!mhuxj!harpo!utah-cs!sask!derek
     NFrom: derek@sask.UUCP (Derek Andrew)
     NNewsgroups: net.test
     NSubject: necessary test
     NMessage-ID: <176@sask.UUCP>
     NDate: Monday, 3-Jan-83 00:59:15 MST
     N
     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.
     N

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  article) and makes it
harder for software to give different priorities  to  news
and mail.

                          - 15 -
 


4.3  Batching

Since news articles are usually short, and since  a  large
number  of  messages are often sent between two sites in a
day, it may make sense to batch  news  articles.   Several
articles  can  be  combined  into one large article, using
conventions agreed upon in advance by the two sites.   One
such  batching  scheme is described here; its use is still
considered experimental.

News articles are combined into a script, separated  by  a
header of the form: