Here we discuss the basic concepts behind the operation of a Usenet news system.
Xref: news.starcomsoftware.com starcom.tech.misc:211 starcom.tech.security:452 Newsgroups: starcom.tech.misc,starcom.tech.security Path: news.starcomsoftware.com!purva!shuvam From: Shuvam <shuvam@starcomsoftware.com> Subject: "You just throw up your hands and reboot" (fwd) Content-Type: TEXT/PLAIN; charset=US-ASCII Distribution: starcom Organization: Starcom Software Pvt Ltd, India Message-ID: <Pine.LNX.4.31.0107022153490.30462-100000@starcomsoftware.com> Mime-Version: 1.0 Date: Mon, 2 Jul 2001 16:27:57 GMT Interesting quote, and interesting article. Incidentally, comp.risks may be an interesting newsgroup to follow. We must be receiving the feed for this group on our server, since we receive all groups under comp.*, unless specifically cancelled. Check it out sometime. comp.risks tracks risks in the use of computer technology, including issues in protecting ourselves from failures of such stuff. Shuvam > Date: Thu, 14 Jun 2001 08:11:00 -0400 > From: "Chris Norloff" <cnorloff@norloff.com> > Subject: NYSE: "Throw up your hands and reboot" > > When the New York Stock Exchange computer systems crashed for 85 > minutes (8 Jun 2001), Andrew Brooks, chief of equity trading at > Baltimore mutual fund giant T. Rowe Price, was quoted as saying "Hey, > we're all subject to the vagaries of technology. It happens on your > own PC at home. You just throw up your hands and reboot." > > http://www.washingtonpost.com/ac3/ContentServer?articleid=A42885-2001Jun8&pagename=article > > Chris Norloff > > > This is from -- > > From: risko@csl.sri.com (RISKS List Owner) > Newsgroups: comp.risks > Subject: Risks Digest 21.48 > Date: Mon, 18 Jun 2001 19:14:57 +0000 (UTC) > Organization: University of California, Berkeley > > RISKS-LIST: Risks-Forum Digest Monday 19 June 2001 > Volume 21 : Issue 48 > > FORUM ON RISKS TO THE PUBLIC IN COMPUTERS AND RELATED SYSTEMS (comp.risks) > ACM Committee on Computers and Public Policy, > Peter G. Neumann, moderator > > This issue is archived at <URL:http://catless.ncl.ac.uk/Risks/21.48.html> > and by anonymous ftp at ftp.sri.com, cd risks . > |
NNTP is the de facto mechanism of choice for moving queued newsfeeds for carrier-class Usenet servers on the Internet, and unfortunately, for a lot of other Usenet servers as well. The reason why we find this choice unfortunate is discussed in Section 12.1> below. But in NNTP feeds, an intermediate step of building batches out of queue files can be eliminated --- this is both its strength and its weakness.
In the case of queued NNTP feeds, articles get added to queue files as described above. An NNTP transmit process periodically wakes up, picks up a queue file, and makes an NNTP connection to the downstream server. It then begins a processing loop where, for each queued article, it uses the NNTP IHAVE command to inform the downstream server of the article's message~ID. The downstream server checks its local repository to see whether it already has the message. If not, it responds with a SENDME response. The transmitting server then pumps out the article contents in plaintext form. When all articles in the queue have been thus processed, the sending server closes the connection. If the NNTP connection breaks in between due to any reason, the sending server truncates the queue file and retains only those articles which are yet to be transmitted, thus minimising repeat transmissions.
> A queued NNTP feed works with the sending server making an NNTP connection to the receiving server. This implies that the receiving server must have an IP address which is known to the sending server or can be looked up in the DNS. If the receiving server connects to the Internet periodically using a dialup connection and works with a dynamically assigned IP address, this can get tricky. UUCP feeds suffer no such problems because the sending server for the newsfeed can be the UUCP server, i.e. passive. The receiving server for the feed can be the UUCP master, i.e. the active party. So the receiving server can then initiate the UUCP connection and connect to the sending server. Thus, if even one of the two parties has a static IP address, UUCP queued feeds can work fine.
Thus, NNTP feeds can be sent out a little faster than the batched transmission processes used for UUCP and other older methods, because no batches need to be constructed. However, NNTP is often used in newsfeeds where it is not necessary and it results in colossal waste of bandwidth. Before we study efficiency issues of NNTP versus batched feeds, we will cover another way feeds can be organised using NNTP: the pull feeds.
NEWNEWS comp 15081997 |
Xref: news.starcomsoftware.com control:814217 Path: news.starcomsoftware.com!linux594.dn.net!news.dn.hoopoo.com! feed-out.newsfeeds.com!newsfeeds.com!feed.newsfeeds.com! newsfeeds.com!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu! newsfeed.icl.net!newsfeed.skycache.com!Cidera!newsfeed.gamma.ru! Gamma.RU!carrier.kiev.ua!goblin.nadrabank.kiev.ua!not-for-mail From: tale@uunet.uu.net (David C Lawrence) Newsgroups: news.groups,humanities.hipcrime Subject: cmsg newgroup humanities.hipcrime Control: newgroup humanities.hipcrime Date: Sun, 18 Feb 2001 11:50:28 GMT Organization: The Cabal Lines: 20 Approved: tale@uunet.uu.net Message-ID: <3afWYZTIR.G5YOC2@uunet.uu.net> NNTP-Posting-Host: 203.145.147.67 X-Trace: goblin.nadrabank.kiev.ua 982528840 21455 203.145.147.67 (18 Feb 2001 20:40:40 GMT) X-Complaints-To: usenet@nadrabank.kiev.ua NNTP-Posting-Date: 18 Feb 2001 20:40:40 GMT X-No-Archive: Yes humanities.hipcrime is an unmoderated newsgroup which passed its vote for creation by 326:10 as reported in news.announce.newgroups on 18 Feb 2001. For your newsgroups file: humanities.hipcrime HipCrime for Humanity - you committed one now! Anyone can create a newsgroup in the alt, biz, comp, earth, humanities, misc, news, meow, rec, sci, soc, talk, us, or any other Usenet hierarchy. New newsgroup proposals may be optionally discussed in news.groups. Please be sure that your /usr/lib/news/control.ctl is configured correctly: ## NEWGROUP MESSAGES ## honor them all and log in \${LOG}/newgroup.log newgroup:*:alt.*|biz.*|comp.*|earth.*|humanities.*|misc.*|news.*|\ meaw.*|rec.*|sci.*|soc.*|talk.*|us.*:doit=newgroup ## RMGROUP MESSAGES ## drop them all and don't log rmgroup:*:*:drop Meow! David C Lawrence |