Path: utzoo!attcan!uunet!lll-winken!lll-lcc!ames!elroy!judy!stevo From: stevo@judy.Jpl.Nasa.Gov (Steve Groom) Newsgroups: news.software.b Subject: Grading of UUCP news traffic Keywords: Different UUCP grades for articles vs control messages? Message-ID: <7182@elroy.Jpl.Nasa.Gov> Date: 30 Jun 88 21:18:15 GMT Sender: uucp@elroy.Jpl.Nasa.Gov Reply-To: stevo@elroy.Jpl.Nasa.Gov (Steve Groom) Organization: Image Analysis Systems Grp, JPL Lines: 67 We have been slowly adding Trailblazer news feeds using ihave/sendme. However, for some sites we deal with (including us), 'blazer time can be hard to come by. You know, several modems available, but the 'blazers are busy or just not available at all hours. What we do now is put a grade limitation on the slower modems so that it doesn't try to send news over a slow line if the 'blazer(s) is/are busy, but holds news waiting for the 'blazer. What I would like to do is be able to send news control messages across the slow lines, and just reserve actual article traffic for the 'blazers. (For those of you unfamiliar with 4.3 BSD UUCP grading: for UUCP commands such as uux you can specify a 'grade'. Then in the L.sys file, along with the time-to-call information, you can specify the minimum grade permissible for jobs when connecting on that line. Jobs not qualifying remain queued and are not run until the line grade allows it. By putting mail at a different grade from news and setting the minimum grade for a slow line somewhere in between the two, you can restrict a line to mail only.) Since we run ihave/sendme, I would like to be able to get those ihave's and sendme's out to the other system as soon as possible, and at the same time not worry about having news flow over slow lines. This would, I believe, make the protocol more effective, as timely replies help reduce redundant traffic. It would also help ensure that the sender had articles ready to go when the fast line does become available, and time wouldn't be wasted with the exchange and processing of ihave's and sendme's during that time. Doing something like this might also help improve the effectiveness of cancel messages, by allowing them to propogate at a higher "priority" than the regular message. One drawback to giving all control messages a higher priority (that you've probably already thought of) is that "sendsys" messages could also flood the net that much faster. (Note: we're running news 2.11 patch 14) The mechanism I would propose to implement this would be to use different UUCP grades for control messages and article batches. Since news uses the same uux flags (which include the UUCP grade specification) for everything it sends, setting this up requires more than just a header fix and recompile. (Actually, the flags are specified once in the 'localize' script and copied everywhere else during the install.) The quick solution would be to fix sendbatch and inews (actually defs.h) directly after localize had been run. Sendbatch invokes uux to send articles and inews invokes uux to send control messages, so I think that would allow a 'control message' grade and an 'article batch' grade. An extravagant solution might be to set up the software with several different sets of uux flags which could be specified from 'localize', with perhaps a different set of flags for each type of control message, and another for article batches. I'm sure that, in practice, this would be overkill. I would like to hear what others think about this. I will be hacking a bit locally for my own purposes, but I thought that this might be of general interest and a possibility for inclusion in later releases. -steve /* Steve Groom, MS 168-522, Jet Propulsion Laboratory, Pasadena, CA 91109 * Internet: stevo@elroy.jpl.nasa.gov UUCP: {ames,cit-vax}!elroy!stevo * Disclaimer: (thick German accent) "I know noothingg! Noothingg!" */