1321 lines
47 KiB
Plaintext
1321 lines
47 KiB
Plaintext
Volume 3, Number 7 17 February 1986
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| / \ |
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| - Fidonews - /|oo \ |
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| Fido and FidoNet _`@/_ \ _ |
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| Users Group | | \ \\ |
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| Newsletter | (*) | \ )) |
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| ______ |__U__| / \// |
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| / FIDO \ _//|| _\ / |
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| (________) (_/(_|(____/ |
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| (jm) |
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Editor in Chief: Thom Henderson
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Chief Procrastinator Emeritus: Tom Jennings
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Fidonews is published weekly by SEAdog Leader, node 1/1.
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You are encouraged to submit articles for publication in
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Fidonews. Article submission standards are contained in the
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file FIDONEWS.DOC, available from node 1/1.
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Disclaimer or don't-blame-us:
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The contents of the articles contained here are not our
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responsibility, nor do we necessarily agree with them.
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Everything here is subject to debate.
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Table of Contents
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1. EDITORIAL
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IFNA and You
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2. ARTICLES
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Software Tools in Pascal available on Fido 143/12
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Exploring MSDOS file structures
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Where Oh Where Can that Interrupt Be?
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Announcing two new newsletters
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Encryption, Public Keys and Otherwise
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XMODEM protocol benchmark
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3. COLUMNS
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Notes from Abroad
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4. FOR SALE
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DEC 11/23 Minicomputer for sale
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Entertainment Software for your PC!
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File Security and Secret*File
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5. NOTICES
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The Interrupt Stack
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Higher Education Net proposed
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New Host for MetroNet
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Orange County is no longer part of SoCalNet
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New Version of Rovermsg Available
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============================================================
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EDITORIAL
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============================================================
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IFNA and You
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IFNA? Wazzat? Well, maybe I should explain a bit first.
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There's been some idle chatter (idle typing?) lately about
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IFNA, but most people probably don't know what it's all
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about. For that matter, nobody really knows what it's all
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about yet, because it doesn't exist yet. At the moment, it
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is nothing more than a dream.
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Ken Kaplan and Ben Baker have been coordinating FidoNet
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activities for quite some time now. I'm not sure just how
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long, since they started doing it before I joined the net,
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and well before I started editing this newsletter. In all
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that time they've seen it grow from a handful of hobbyists
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to a major electronic mail system.
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Yes, yes, I'm talking about the FidoNet we all know and
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love. You may not realize it, but we (all of us, you too)
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are now running an international network on par with the
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major commercial nets. We're getting noticed, too. Refer-
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ences to Fido and FidoNet are becoming more and more common
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in the trade journals.
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We're also a public service, now. Those articles about
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FidoNet for the deaf and blind weren't just hot air. There
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are deaf people right now using FidoNet as a means to
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contact the rest of the world.
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Even this modest little publication is becoming widely read
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among those in the know, much to my surprise. Awhile back
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an article here stimulated, in a matter of days, a response
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by phone from the president of a major corporation (I won't
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say who, except to note that it's a Fortune 500 company),
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just to mention one incident. I must admit that I am not
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used to having my words quite so widely read, immortal prose
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though they may be.
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But back to Ken and Ben. They've watched all this grow, and
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have been thinking (and worrying) about how to handle it if
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it keeps growing. Perhaps I should say "when it grows even
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larger", as it shows every sign of growing bigger and bigger
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as time goes by.
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One thing they saw right off. FidoNet would soon (say about
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last Tuesday) get big enough that it would require someone
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working full time to hold it all together. This is no sur-
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prise to me; I've seen much the same situation in other
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groups I belong to. The big question, of course, is how to
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finance such a thing, particularly without reducing or
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charging for the many services we already enjoy.
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Fidonews Page 2 17 Feb 1986
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This is where the International FidoNet Association (IFNA)
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comes in. The general idea is to set up a not-for-profit
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service organization to provide services to FidoNet sysops
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and users. There are three main ways that this can be
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financed:
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1. Voluntary contributions from individuals and corpora-
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tions. There is a trickle of this now, and we can
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expect it to grow once IFNA is registered as a non-
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profit organization.
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2. Fees for new services not currently provided, such as
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the printed FidoNet magazine.
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3. Fees for providing commercial services to outside
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companies.
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As you can see, they're trying to come up with ways of
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paying for our hobby that don't call for coercing anyone
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into paying for things they don't want.
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Probably all three methods will be used, but the one that
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really interests me is number three. One example I've heard
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of it is collecting data for market research companies. The
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general idea is that participating sysops use the question-
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naire ability of Fido to collect the data, which is then
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sent to a central collection point that bills the outside
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company. Participating sysops get money back, depending on
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the amount of data collected. Sysops who don't want to
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participate don't have to.
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And THAT I like. Nobody is forced to do anything they don't
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want, and everybody has a chance to make a few bucks while
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helping out. All winners, no losers. That's really the
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whole point of IFNA, to figure out ways to benefit everyone
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on the net.
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Fidonews Page 3 17 Feb 1986
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============================================================
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ARTICLES
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============================================================
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Programs From
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"Software Tools in Pascal"
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Now Available on the
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Wyrld Wyrm BBS, Fido 143/12
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"Software Tools in Pascal", by Kernighan and Plauger
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(Addison-Wesley, 1981, $16.95) is a book on programming
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techniques that demonstrates good coding by building up a
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set of useful programming tools. These include an editor, a
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find-and-replace utility, a text formatter, and a number of
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smaller utilities, all useful.
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The authors have granted permission for noncommercial use
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and distribution of the software presented in the book. A
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version of the software, modified slightly to run under
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Turbo Pascal, appeared on the USENET (in mod.sources) a few
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months ago.
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These files, (edited slightly by me to eliminate a few
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glaring bugs) are available on my BBS, the Wyrld Wyrm BBS,
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Fido 143/12 (408) 263-8134. My BBS run 22 hours per day,
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with the two hours between 00:30 and 2:30 taken up by
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FidoNet. The file is about 50k long, and can be downloaded
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in under ten minutes at 1200 baud.
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While the programs are useful in themselves, they're
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invaluable as a Pascal source code library. Many routines
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that people tend to reinvent (sorting, string searching,
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etc.) are right there for the taking.
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I should warn you, though, that you'll need the book if
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you want to use these programs. The command line syntax,
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while simple, isn't obvious, and the person who typed in all
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the code left out the comments (assuming that you had the
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book in front of you, I suppose). The book is really good,
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though, so it's money well spent.
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-- Robert Plamondon
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Sysop, Wyrld Wyrm BBSs
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Fido 143/12
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Fidonews Page 4 17 Feb 1986
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Richard A. Karas
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Fido 107/29
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Exploring MSDOS File Structures
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Disks (floppy as well as hard) are formatted or initialized
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under MSDOS Version 2.0 to allow fast and convenient access
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to files. MSDOS supports several methods of accessing
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files. The handle method, the File Control Block method,
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and the direct access method through directory and the File
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Allocation Table (FAT) search. The handle and FCB methods
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require you to access files through the operating system and
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their respective function calls, while the direct method
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enables you to access files as it implies, directly. To
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access files directly, a little knowledge of the way MSDOS
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formats the disk is required. MSDOS disks after formatting
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contain the following structures in sequence:
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o Reserve boot loader area.
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o First copy of the FAT.
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o Second copy of the FAT (for recovery purposes).
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o Root directory.
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o Data area.
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Utility programs read the reserved boot area where disk
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media data may be found. This data provides the program with
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information about the device. Typically byte offsets 11
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through 29 have been set aside to define all the necessary
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attributes required.
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Disk space is allocated in the data area only when required
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and is accomplished in one allocation unit at a time. An
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allocation unit is referred to as a cluster and is represen-
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ted by one or more consecutive sectors. A sector is usually
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512 bytes. A cluster will contain from 1 to x sectors depen-
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ding upon the media. Some typical allocations are:
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o Double sided floppies 2 sectors/cluster.
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o 10mb hard 8 sectors/cluster.
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o 20mb hard 16 sectors/cluster.
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This method of storage presents some problems to the user
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(especially those running BBS systems) who store many small
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files. Consider storing 100 files of text containing ap-
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proximately 200 bytes each file on a 10mb hard disk (Like
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Fido stores messages). Figuring 8 sectors/cluster X 512
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bytes/sector = 4096 bytes per allocation unit. 100 alloca-
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tion units would be needed (providing each file only needs
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one allocation unit each) at 4K per representing 400K bytes
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of storage for 100 files. You are only actually storing 200
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bytes X 100 files or 20K bytes of data ( a very big waste of
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space). DOS 3.1 attempts to solve this problem by allowing
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Fidonews Page 5 17 Feb 1986
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the user to define the cluster size. Enough about problems,
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back to file storage techniques using the direct method
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(reference back Fido news issue).
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When information is written to the disk, the system looks
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for the cluster that is closest to the beginning of the data
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area and available. This criteria can easily be fulfilled
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by checking the FAT. The FAT maps every cluster of the data
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area and is in fact a large linked list to files occupying
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more than one cluster. FAT data is stored 1.5 bytes per
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cluster, with cluster #2 defined as the start of the data
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area. The first two FAT entries represent system data, entry
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3 through X actually map the entire disk. The value of each
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FAT entry could be one of the following:
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o 000H Unused cluster.
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o 002H-ff6H Next cluster of data.
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o ff7H Bad cluster.
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o ff8H-fffH Last cluster of file.
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The root directory is initially built at the time of disk
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format. It is a fixed value of clusters depending upon the
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size of the media. Each directory entry is 32 bytes in
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length and contains information required by the system to
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locate files. Since directories other than the root direc-
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tory are actual files, there is no limit to the number of
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entries they may contain. Reference the DOS manual for a
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complete description of the fields of a directory entry.
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For now all that you should know is that fields 00-07H
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contain the file name, 08-0aH contain the extension, and 1a-
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1bH contain the starting cluster number.
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The following brief discussion describes file access using
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the direct method (assume root directory only):
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1. The media data is read to obtain the necessary informa-
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tion as to number of sectors, where the root dir starts,
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how big it is, etc.
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2. The Root directory is read.
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3. Each 32 byte entry is scanned until the correct file is
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located.
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4. The starting cluster number at offset 1a/1bH of that
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directory entry is obtained and converted to logical
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sector number.
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5. X number of sectors per allocation is read to a transfer
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address starting at the sector calculated above. (X
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sect/allocation unit is a function of the media).
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6. Next the FAT map is checked to see if additional
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clusters must be read. This is accomplished by conver-
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ting the cluster just read from the directory entry to
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Fidonews Page 6 17 Feb 1986
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an offset value into the FAT. If the 1.5 bytes represen-
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ting the starting cluster contains data pointing to
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additional clusters, the system will read that cluster.
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This next mapped cluster entry will be checked and the
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process will continue until the last cluster is read.
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The following visually represents the process:
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DIRECTORY (Entry #3)
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___________________________________________________
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| | | Name.ext | | |
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| 1 | 2 | start cluster---- | X |
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|_____|_____|_____etc.______|_|_________________|____|
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___________|______
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_________| Routine to |
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| | access data |
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_________|_
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| | FILE ALLOCATION TABLE
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| ______2_|_____________5__________________________X__
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| | sys | 5 | | FFF| | |
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| |_____|_____|________|____|_____________________|____|
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| |_____________|
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|____ DATA AREA
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| _|__________________________________________________
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| | | | | _ | | |
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| | 2 | 3 | | 5 | | X |
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| |_____|_____|___________|____|__________________|____|
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|___________________________|
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The conversion of cluster number to logical sector and
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determining the byte offest into the FAT is simple. The
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method is written in any DOS manual near the system calls
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section. One trick which is not mentioned is that the
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formula to determine offset into the FAT table will only
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work if you operate on the table as if each byte were an
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entry ( that is if you read the table as bytes, and not
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words).
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I hope this small article has been of some help to the
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readers in understanding some of the file storage techniques
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of the MSDOS operating system. One example of using this
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method of file access is depicted in the public domain 'C'
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program DSKRPK.ARC located on Fido 107/29.
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------------------------------------------------------------
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Fidonews Page 7 17 Feb 1986
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Where Oh Where Can that Interrupt Be?
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I need some help, please. Maybe I am looking at the wrong
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elements in my system, but I have had a rash of
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communications problems lately.
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My system is a PCXT with a Hayes 1200b and fully populated
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Quadram Quadboard installed. My comm port is COM2: My
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problems is this:
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Since installing the Quadboard, I have had problems with
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telecommunications. I had installed the Quadram print
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spooler and clock device driver. When I would connect, the
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modem would return strange baud rate values, such as 20, or
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120, etc. I am using Pibterm as a comm program. Removing
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the print spooler from CONFIG.SYS solved this, I think.
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Now, I occasionally will have connection problems. Connec-
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tion is made, the remote tone is audible, but my system
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doesn't respond. This is rare and may be an artifact of a
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noisy non-Bell long distance service. Modem testing
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revealed no problems. Could it be a problem with the clock
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driver?
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I have removed it from CONFIG.SYS and am only using the
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clock setting .EXE file in my AUTOEXEC.BAT. A colleague
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thinks it is a conflict between the interrupts used in the
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clock device driver and the communications system.
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If you have any ideas please let me know. If you know of a
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print spooler that doesn't cause problems with communica-
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tions, please let me know about it, too.
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Thanks for your help.
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Bill Allbritten, 11/301
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Fidonews Page 8 17 Feb 1986
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Two New Newsletters for Fidonet
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Fidonet PCNews
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and
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Fidonet Languages
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Fidonews is an excellent way of getting news and information
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across the network to both the sysops and users of Fido
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boards. The nature of the articles though usually relates
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to Fido itself or to BBS's in general. The articles are
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also written primarily by sysops, perhaps because of the
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restriction of file attaches to users with sysop or extra
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privileges. There is nothing really wrong with this focus
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of Fidonews, the newsletter serves a very needed purpose in
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the network. Something more is needed though.
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What I propose is a concept similar to the news groups of
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Usenet. I would like to see one or more new newsletters
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built from netmail messages instead of from file attaches,
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thus making the newsletters more accessible to all users.
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The content of each newsletter would be focused on one
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specific subject, not necessarily having anything to do with
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computers. As an experiment, I am going to try and get the
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first of these going from The Ark Tangent. The two
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newsletters I'm going to be putting together are Fidonet
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PCNews and Fidonet Languages. The first will be concerned
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with IBM PC's and clones, while the second will have
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programming languages as its focus.
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Getting information into the newsletters will be simple.
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Send a netmail message to node 137/19 addressed to the name
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of the newsletter you are contributing to, either Fidonet
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PCNews or Fidonet Languages. Weekly, on Tuesday morning,
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the mail for each newsletter will be converted to straight
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text and concatenated into a text file to be distributed
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across the network. Responses to the messages in the
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newsletters could be directed back to the newsletter or the
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author of the message, whichever suits.
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In order to receive the newsletter on your node you will
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need to poll The Ark Tangent (137/19) to pickup an archived
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copy of the file. Send me a note requesting one or both of
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the newsletters and I'll set you up to pick up the files on
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a weekly basis.
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Wes Cowley
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Sysop, The Ark Tangent
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Fido 137/19
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Fidonews Page 9 17 Feb 1986
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Encryption, Public Keys and Otherwise
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PART One.
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If you know what "Public Key Encryption" is then feel
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free to skip to part two.
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Public Key Encryption is a special form of encryption
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which uses different keys for encryption (or scrambling) of
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a message and decryption (unscrambling, the reverse
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operation).
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The separate keys for each operation have several
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advantages. The first is that the encryption key can be
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distributed much more easily by less secure means without
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compromising the security of future encrypted messages.
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Simple knowledge of the encryption key does not enable
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decryption of encrypted messages. The decryption key is
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required to recreate the original message. For this reason
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the encryption key is commonly called the "public key" and
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the decryption key is the "private key".
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In operation, everyone who wants to receive secret
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messages creates their own pair of keys, one private and one
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public. The public key is them communicated to everyone who
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may want to send them a secret message. Perhaps a central
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key distribution center could be established. The private
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key is kept secret and never told to anyone.
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For example ... Art wants to send Beth a secret message.
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He would look up Beth's public key or ask her to send him
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one (in the clear). He would then use Beth's public key to
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encrypt his message and send her the encrypted message. Beth
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receives the message and decodes it with her private key. No
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one else can decrypt the message even if they get a copy of
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the encrypted message AND the public key. They need the
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private key.
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In 1978 the CACM journal published a way of doing this
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on computers. The system they described has come to be known
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as the "RSA" encryption system.
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The RSA system has an additional property beyond the
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general Public Key Encryption system described so far. With
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the RSA system the keys are interchangeable so you can use a
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private key to encrypt a message and then only the
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corresponding public key will unscramble the message. This
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is in effect a "digital signature" which "signs" a message
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showing that the encrypted message could only have been
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created with knowledge of the private key.
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Messages can also be encrypted more than once. For
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example you can sign a message with your private key and
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then encrypt the result again with the intended receiver's
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public key to make a signed, secret message. The receiver
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would then need to do the reverse two steps in the reverse
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order to get the original message back.
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Fidonews Page 10 17 Feb 1986
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Even more complex interaction can be used for special
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purposes. Articles have appeared on how to play poker over
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the phone and how to hold a secret ballot election over the
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phone and others.
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PART Two.
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I have recently completed a Public Key Encryption system
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based on the RSA system. It runs on MS-DOS using files for
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keys and messages. I am distributing the system as
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freeware/shareware. (PKSCrypt 0.0 or 0.01)
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There may be some legal or political considerations in
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this.
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I have heard rumors that this sort of stuff comes under
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certain restrictions for export of high tech (or something)
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from the USA. I don't think this quite applies to me because
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I am exporting the system TO the USA. (I live in Canada).
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I have also heard rumors that some intelligence
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organization (unnamed) is discouraging public discussion
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(let alone utilization) of these systems. I have trouble
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believing this because I had no trouble finding all the
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information I could ever desire on the subject. There was
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even an article in Byte magazine and a couple follow-up
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letters.
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Anyone who has any solid info on this, I would like to
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hear from you. I especially would like to hear directly from
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any government organization(s) (in any country) who may
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think they are involved.
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Interested parties may contact me via Fido node 134/1.
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Lloyd Miller
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Calgary, Alberta
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1986 Janualry 16
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------------------------------------------------------------
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Fidonews Page 11 17 Feb 1986
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Thom Henderson, node 107/8
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System Enhancement Associates
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XMODEM protocol benchmark
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SEA recently performed a series of benchmarks aimed at
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producing a formula for the realistic prediction of file
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transfer times. This report presents the results of that
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benchmark, along with some conclusions about the XMODEM
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protocol and file transfer protocols in general.
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The raw data for the benchmark was collected by transferring
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files of different sizes at different baud rates over local
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phone lines and timing the transfer periods. Files were
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transferred between a Fido BBS system and a PC running
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Minitel, using the XMODEM file transfer protocol with CRC
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error detection. No errors were reported during the
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transfers used in the benchmark study. The raw data may be
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summarized as follows:
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Transfer Times in Seconds
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50 Blocks 100 Blocks
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========= ==========
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300 Baud 236.3 472.3
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1200 Baud 71.1 142.5
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2400 Baud 39.5 80.2
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From this data we deduced the following formula for predic-
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ting file transfer times using integer variables:
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Blocks*1340 Blocks
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Time in seconds = ----------- + ------
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Baud rate 4
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For 50 blocks at 300 baud this would yield 50*1340/300 = 223
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seconds, plus 50/4 = 12 seconds, for a total of 235 seconds.
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The formula varies with the measured times from being 2.6%
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low to being 3.8% high, with an average error of 0.5% low.
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This is considered to be within observational errors.
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Construction of the formula was primarily based on this
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assumption: that file transfer time will be split between
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the time required to send the 134 bytes per block that the
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protocol requires (we are including the ACK sent by the
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receiver), plus overhead time required for each block.
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This gives us a variable time dependent on baud rate, plus a
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fixed overhead which is independent of baud rate. The above
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formula is based on an overhead of 0.25 seconds per block.
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(The actual calculated figure was 0.27 seconds, but this is
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within observational error.) This overhead time can be
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Fidonews Page 12 17 Feb 1986
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attributed to processing delays at either end, line "purge"
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time, and propagation delays. Propagation delays would be
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minimal in a local connection such as this, but would grow
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significant in a long distance connection involving
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satellite relays (at least an additional 0.25 seconds).
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Using a larger block size would help reduce this by reducing
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the number of blocks being transferred, as well as reducing
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the percentage of bytes used for the protocol. The
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percentage of slack time (based on the above formula) at
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different baud rates follows:
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Baud 128 byte blocks 1024 byte blocks
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==== =============== ================
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300 5.3% 0.7%
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1200 18.3% 2.8%
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2400 30.9% 5.5%
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4800* 47.3% 10.5%
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9600* 64.3% 18.9%
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* Formula not backed by benchmark data at this speed.
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As you can see, the 128 byte block size is well suited to
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300 baud transmission, and even acceptable at 1200 baud, but
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rapidly becomes onerous at higher baud rates.
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At first glance a larger block size seems to be an ideal
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solution, since time spent on overhead is acceptable even at
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the higher baud rates. It is my opinion that this is at
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least partly illusory. The above figures are calculated
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assuming a zero error rate. A connection that is even
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moderately noisy will produce enough "hits" to quickly eat
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up any improvements.
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Conclusion: If you can't lick 'em, join 'em.
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XMODEM protocol with CRC error detection achieves a trans-
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mission reliability on par with the best of the major data
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network services, but it suffers in transmission time at the
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higher baud rates. A solution that would be viable at any
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baud rate would be a "sliding window" protocol, something
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like the X.PC protocol.
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However, X.PC suffers from being excessively complicated,
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but it does have the advantage that TymNet has released
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sources for its implementation.
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It may not be necessary to go as far as a full X.PC imple-
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mentation. A sliding window algorithm based on a fixed
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block size should not be difficult to implement.
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------------------------------------------------------------
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Fidonews Page 13 17 Feb 1986
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============================================================
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COLUMNS
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============================================================
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Notes from Abroad
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As I'm sure all you sysops have already found out, this Fido
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lark consumes a lot of time. On top of Fido I also run the
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Compulink User Group, this takes up most of my time, but I
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hope to be able to spend more time on the Fido side in the
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future. I started Compulink just over a year ago and from
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then I have been spending as much time as possible working
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for the group, promoting the public domain software concept,
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and also running Fido. There has always been more work than
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I could squeeze into a day, but, unfortunately not enough
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money was coming in to pay for itself. I have therefore
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been forced to go out to work in the day to subsidize Fido
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and the user group. I have got some pretty big plans for
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Fido and the user group (I consider the two inseparable!),
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but I don't have the money to see them through.
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When I have to go out to work I don't have enough time to
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work on both projects. Fortunately I have received a little
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press coverage in the last few months and this has brought
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in enough money for me to give up my day job. Now I'm not
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making a fortune, in fact most of the money that comes in is
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going straight out again, this is mainly because I
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underpriced all the fees I charge for the user group.
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Unfortunately I have to put up my prices for 86, if I don't
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do this I wont be here this time next year. It's still a
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very good deal joining Compulink, but next year I simply
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can't afford to subsidize membership out of my own pocket.
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In return for my higher fees I hope to be able to plow even
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more of my time into the project and everyone will benefit.
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The next major step I will take is to move into a small
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office. At the moment I am renting my house and the
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landlord won't allow me to install any more telephone lines.
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I am running two Fido's concurrently at the moment,
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eventually I hope to have about 6 incoming lines, a PSS
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data-line and a true multi-user Fido. This will cost a
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fortune but I'm going to do it, when I look at the services
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offered by Telecom Gold, Easylink, et al; I think, Hell, I
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could do better than that!
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As Fido gets more and more powerful (which of course it
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will!) I will be able to offer subscribers more and more for
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their money. What I'm waiting for now is true multi-user
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Fido, one that can support more than one input stream. The
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RBBS-PC bulletin board software (also public domain) has
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just gone multi-user, and I hope Fido will follow shortly.
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I am not expecting Tom Jennings to do this, TJ has done more
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than his share already, and if you haven't done so already;
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I think you should buy the Fido software from Tom as
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detailed in the new manual.
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Any further innovation has to come from us, the Fido sysops,
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Fidonews Page 14 17 Feb 1986
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and of course our users. When a Fido clone has been
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officially accepted as the public domain Fido we can all
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start customizing our own Fido's to our own requirements.
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Till then we take what we get and thank our lucky stars that
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someone cares enough about what we are doing to make
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improvements.
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I'm sorry for going on like this, but I thought I'd tell you
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all how I feel. What I'm really trying to say is this; OK I
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charge people a fee or full access to my system, sure; I
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charge people a fee for copying disks. If you read on
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you'll see the charges I make, they're reasonable, I've also
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sent a copy of the disk magazine I write to all the country
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coordinators to do with what they will, I've also sent out
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my disk catalog.
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I REALLY believe in what I'm doing. If I could afford to do
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all the things I've been talking about I wouldn't be writing
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all this because I would have already done it! I don't
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think it's wrong to charge people for what I'm doing. It's
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the only way I can raise the capital needed to fulfill my
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plans.
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If you have any comments (good or bad) on the above I would
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welcome them.
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------------------------------------------------------------
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Fidonews Page 15 17 Feb 1986
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============================================================
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FOR SALE
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============================================================
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FOR SALE OR TRADE!
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DEC 11/23 Minicomputer as follows:
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11T23 Computer
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CPU card has MMU and FPU
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(2) RL01 5MB Removable Disk Drives
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(4) Disk Packs for RL01
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LA-120 "DECwriter" printing terminal
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(2) 4 serial port "J" cards
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Latest version of RT-11M+ (5.1)
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Misc documentation
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This computer is about six years old, but was only used for
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about a year of that time, so it's had VERY little use.
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I'd be interested in:
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A cash offer
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Trade for:
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(1) ea IBM-PC/AT system or
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(2) ea DEC Rainbow (w/hard disk) systems or
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(1) ea grand piano
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This is available in Portland, OR and shipping would
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probably be prohibitive (extremely heavy, like a small
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refrig), but it's your nickel (FOB Portland).
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Contact me for further information:
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Doug Forman, Sysop
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MacSystem/NW 105/8
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(503) 233-6583 BBS
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(503) 236-8160 Eves
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(503) 357-6151 x2295 Days
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------------------------------------------------------------
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Fidonews Page 16 17 Feb 1986
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ENTERTAINMENT SOFTWARE FOR YOUR PC!
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SUPERDOTS! KALAH!
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Professional quality games include PASCAL source! From the
|
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author of KALAH Version 1.6, SuperDots, a variation of the
|
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popular pencil/paper DOTS game, has MAGIC and HIDDEN DOT
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options. KALAH 1.7 is an African strategy game requiring
|
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skill to manipulate pegs around a playing board. Both games
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use the ANSI Escape sequences provided with the ANSI.SYS
|
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device driver for the IBM-PC, or built into the firmware on
|
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the DEC Rainbow. Only $19.95 each or $39.95 for both
|
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exciting games! Please specify version and disk format.
|
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These games have been written in standard TURBO-PASCAL and
|
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run on the IBM-PC, DEC Rainbow 100 (MSDOS and CPM), CPM/80,
|
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CPM/86, and PDP-11. Other disk formats are available, but
|
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minor customization may be required.
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BSS Software
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P.O. Box 3827
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Cherry Hill, NJ 08034
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For every order placed, a donation will be made to the Fido
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coordinators! Also, if you have a previous version of KALAH
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and send me a donation, a portion of that donation will also
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be sent to the coordinators. When you place an order, BE
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CERTAIN TO MENTION WHERE YOU SAW THE AD since it also
|
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appears in PC Magazine and Digital Review.
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Questions and comments can be sent to:
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Brian Sietz at Fido 107/17
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(609) 429-6630 300/1200/2400 baud
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------------------------------------------------------------
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Fidonews Page 17 17 Feb 1986
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Daniel D. Stuhlman
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BYLS Fido (no node number yet)
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File Security and Secret*File
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Security is a frequent problem with computer use. If you
|
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have a large number of personal computer users who need to
|
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share files how do they insure that only the intended
|
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receiver reads the file?
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|
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Secret*File from BYLS Press is a file encryption program for
|
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everyone who wants to share secure MS-DOS files. Secret*File
|
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is menu-driven and easy-to-use. Program requires an IBM-PC
|
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compatible computer with MS-DOS 2.1 or higher, 128K RAM,
|
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and one 5" disk drive.
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Examples of uses:
|
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1. Send a coded file to a friend via modem.
|
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2. Upload a coded file. Let a friend download it.
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3. Put a coded file on a disk. Send disk to a friend.
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4. Send coded messages from field offices to home office.
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Secret*File offers the following security features:
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1. User name and password required to operate program.
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2. User and receiver must know exact file name.
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3. Two types of coding.
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4. User may change random number files needed for coding.
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5. File's password is not stored.
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6. Decoy bytes and check digits make cryptoanalysis
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difficult.
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Secret*File codes and decodes at the rate of 50 bytes per
|
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second. Disk is not copy protected and may be used on a hard
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disk.
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Single copies of Secret*File cost only $75 and include a
|
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free copy of Print*File. Print*File is a printer control
|
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utility to allow use of the fonts offered on an Epson
|
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compatible printer.
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Quantity and dealer discounts and site licenses are
|
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available. A demo version and more information may be
|
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downloaded from BYLS Fido board 312-262-8959 (11 PM - 9 AM
|
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weekdays, all day Saturdays Central Time zone)
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Order or request more information from:
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BYLS Press
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6247 N Francisco
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Chicago, IL 60659
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------------------------------------------------------------
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Fidonews Page 18 17 Feb 1986
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============================================================
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NOTICES
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============================================================
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The Interrupt Stack
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22 Feb 1986
|
|
Submissions deadline for the CROBOTS competition. Ask
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Andy Foray at 107/7 for details.
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1 Mar 1986
|
|
The Next Occasional MetroNet Sysop Meeting, to be held at
|
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Matt Kanter's apartment. Check with Matt at 107/3 for
|
|
details.
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1 Mar 1986
|
|
European mail hour shifts to 0230-0330 GMT. Summer time
|
|
will no longer be observed.
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11 Apr 1986
|
|
Halley's Comet reaches perigee.
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19 May 1986
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Steve Lemke's next birthday.
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24 Aug 1989
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Voyager 2 passes Neptune.
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If you have something which you would like to see on this
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calendar, please send a message to Fido 1/1.
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Fido 11/301, Fido Racer, Murray State University, and Fido
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144/2, Fido CSU, Colorado State University, are interested
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in forming a network of FIDO's at institutions involved in
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advanced education -- colleges, universities, medical
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schools, institutes, and the like. If you are interested,
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drop a line to 11/301 expressing interest.
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We may be able to get some interesting exchanges going in an
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area that doesn't seem to be represented in a net at this
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time. We look forward to hearing from you.
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Bill Allbritten, sysop, 11/301
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Net 107 has a New Host
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Due to our previous host's serious and ongoing phone line
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problems, Don Daniels is now the host for net 107, as of
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Fidonews Page 19 17 Feb 1986
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node list #038.
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The Orange County section of NET 102 has broken out to a
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separate net. This change is effective as of node list 031.
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Our new net is 103. All the 500 series nodes from new 102
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are now addressed as net 103 with the same node numbers.
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103/501, Host of net 103
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New Version of Rovermsg Available
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by
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Bob Hartman
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Sysop Fido 132/101
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The UN*X Gateway
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and Home of Rovermsg
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Once again there is a new version of ROVERMSG available for
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downloading from my board. The new version is Revision
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2.16. This version has some small bug fixes, and also
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allows faster video display on IBM PC's, DEC Rainbows, and
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Sanyos. The new video display is about 2-3 times faster
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than it used to be. Anyone who is using a previous version
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of Rovermsg should update to the new version if possible.
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------------------------------------------------------------
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Fidonews Page 20 17 Feb 1986
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