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400 lines
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
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<html><head>
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<META NAME="generator" CONTENT="lgazmail v1.1preB">
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<TITLE>The Answer Guy 32:
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Permission to Set up a Linux Server
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<!-- ORIGINAL SUBJECT:
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Mail and misc Linux Servers
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<BODY BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#A000A0"
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ALINK="#FF0000">
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<H4>"Linux Gazette...<I>making Linux just a little more fun!</I>"
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</H4>
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<P> <hr> <P>
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<!-- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -->
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<H1 align="center"><A NAME="answer">
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<img src="../gx/dennis/qbubble.gif" alt="" border="0" align="middle">
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<a href="./index.html">The Answer Guy</a>
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<img src="../gx/dennis/bbubble.gif" alt="" border="0" align="middle">
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</A></H1>
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<BR>
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<H4 align="center">By James T. Dennis,
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<a href="mailto:linux-questions-only@ssc.com">linux-questions-only@ssc.com</a>
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<BR>Starshine Technical Services, <A HREF="http://www.starshine.org/">http://www.starshine.org/</A>
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</H4>
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<p><hr><p>
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<!--endcut ========================================================= -->
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<H3><img src="../gx/dennis/qbub.gif" alt="(?)"
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width="50" height="28" align="left" border="0"
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>Permission to Set up a Linux Server</H3>
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<p><strong>From ChipX on 20 Aug 1998 </strong></p>
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<!-- begin body -->
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<p><strong>Hi,
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OK, just a quick question (sort of)...
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</strong></p>
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<p><strong>My friend came over one day and we were just surfing like usual
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(using Win95).
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</strong></p>
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<p><strong>He asked if he could check his mail; I said "Sure."
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So he opens up telnet and logs onto a friend's RedHat Linux 4.2 Server.
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He checks mail, updates his finger, and leaves.
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</strong></p>
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<p><strong>I really need to know how to set up a server of my own.
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</strong></p>
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<p><strong>Do I need my isp's permission or some junk like that, cuz they wont be
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willing to give up any of their ethernet for me and my linux box <IMG SRC="../gx/dennis/smily.gif" ALT=":)" height="24" width="20" align="middle">
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</strong></p>
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<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
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alt="(!)" border="0"
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>Alright, I finally figured out what you were asking.
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It took a little work, though.
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</blockquote>
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<blockquote>First note: when you set up a Linux system it defaults
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to providing many services. It is already a "server."
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</blockquote>
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<blockquote>What you seem to be asking is: "How do I make my server
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accessible via the Internet?"
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</blockquote>
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<blockquote>As you surmised you would have to make arrangements with
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some ISP to have some dedicated (or at least "dial on demand")
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connection to the net, or to "co-locate" your hardware with
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them.
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</blockquote>
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<blockquote>There are a number of ISP's that provide co-location services.
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This is where you provide a system that they plug into
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their network (and power). Generally these are moderately
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expensive services (about $150 to $500 per month usually with
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a limited average bandwidth utilization per month).
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</blockquote>
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<blockquote>Some of these plug you into their ethernet, others provide a
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null modem (serial) connection over which you'd configure a
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"local" (direct) PPP link. This allows them to effectively
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limit the amount of bandwidth you're using. (The latest 2.1
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Linux kernels have an experimental "shaper" interface that
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allows one to limit bandwidth utilization on ethernet --- but
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I don't know of any ISP that's using that).
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</blockquote>
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<blockquote>I know some businesses that co-locate an extra server for
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redundancy. If their dedicated network connection gets
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hit by the proverbial (and sometime very <EM>real</EM>) 'backhoe'
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then their web site and mail server is still accessible to
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their customers. This is relatively low cost to companies
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that are used to paying for T-1, T-3, or fiber charges.
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</blockquote>
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<blockquote>This brings up to the second option. You can get a
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dedicated connection to your home or office. These range
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from 28.8 dial-up over POTS (plain old telephone service) to
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OC-48 (optical connections --- even past 622Mbps). As you
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might expect most of these are prohibitively expensive
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for home use (not to mention potential zoning and regulatory
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issues).
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</blockquote>
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<blockquote>For practical purposes you have the following options for
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home and SOHO (small office, home office) dedicated connections:
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</blockquote>
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<blockquote>
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<dl><dt>modem over POTS:
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<dd>least expensive, might be as low as
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$130 (US) per month. Slowest. As
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discussed in my articles about modems
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you usually won't get 56Kbps out of a
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"56K" modem.
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<dt>ISDN (Centrex or not):
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<dd>This is usually at least $200/mo.
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Centrex is a little confusing. Typically it
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allows you and your ISP, if you are located in the
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same telephone CO (central office), to have an
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ISDN line that is essentially an extension of
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your ISP's office. This typically just eliminates
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the "per-minute" charges of keeping the ISDN line
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up. It also limits your ISDN line so that it can
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only be used with that ISP. (This also implies
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a very limited selection of ISP's for each user).
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<dt>DSL:
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<dd>Not available in all areas. Somewhat confusing
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right now since it is a fairly recent offering.
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Basically DSL takes advantage of an old obscure
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feature in the pricing structure and responsibilities
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of US phone companies. They used to provide "dry
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copper" lines (that is telephone wires with no
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dial-tone or signal) to alarm companies and similar
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services. Using these lines and connecting DSL
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routers at each end (rather than alarm monitoring
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equipment) one can get various speeds (depending
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on the distances between client, CO, and ISP).
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</dl>
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</blockquote>
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<blockquote>DSL typically costs about $300/mo where it's
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available.
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</blockquote>
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<blockquote>If I was getting a DSL line I'd get it
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from Idiom (<A HREF="http://www.idiom.com">http://www.idiom.com</A>) or some other
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Covad partner (<A HREF="http://www.covad.com">http://www.covad.com</A>). I know
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the owner and founder of Idiom, and one of the
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principles of Covad. Those are both SF Bay
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Area companies.
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</blockquote>
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<blockquote>
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<dl><dt>56K leased line:
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<dd>(I'm not a telco expert but I think this
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is the same as a "fractional T1" --- that is that
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is a a fraction, 1/24th of a T-1 --- which in
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turn is a bundle of 24 channels for a total of
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1.54Mbps). This is about as much as any sane
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person would pay to put in his or her home. They
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cost about $300 or more per month.
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<dt>cablemodem:
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<dd>These are very fast, and only available
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in a <EM>very</EM> limited number of places. Also
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they frequently limit your ability to provide
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services (through packet filtering or by
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periodically disconnecting you and assigning
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new IP addresses. While they sound great for web
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<dt>Frame Relay:
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<dd>I've seen these in various speeds, from
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56K or 64Kbps to 1.5Mbps and in various prices
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ranging from $200 per month to over $1000.
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<dt>Wireless:
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<dd>A couple of providers in the Silicon Valley
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(and San Francisco Bay Area) offer wireless
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dedicated connections. One of them is
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Innetix (<A HREF="http://www.innetix.com">http://www.innetix.com</A>)
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</dl></blockquote>
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<blockquote>Conceivably an ISP could provide "dialout" or "service
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on demand" services --- that is that they could dynamically
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dial your server when TCP/IP traffic is destined for your site.
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(It would work almost the same way that your copy of diald
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allows your system to dynamically call your ISP --- only the
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underlying routes would be different).
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</blockquote>
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<blockquote>I've never heard of a company that actually offered this
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service and I doubt that there's any advantage for them to
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do so. This would probably be quite expensive for them ---
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and there's probably almost no demand for it (I doubt that
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one customer in a thousand would understand or care about
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such a service --- and I can see any pricing niche that would
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make it worthwhile).
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</blockquote>
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<blockquote>I only mention as a theoretical possibility.
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</blockquote>
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<strong><p><img src="../gx/dennis/qbub.gif" height="28" width="50"
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alt="(?)" border="0">Can I do this with X?</p></strong>
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<strong><p>Thanks.
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<br>ChipX
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</p></strong>
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<blockquote><img src="../gx/dennis/bbub.gif" height="28" width="50"
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alt="(!)" border="0"
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>X is a communications protocol for windowing (GUI)
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and keyboard/mouse events. The X Window System provides
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a client/server windowing environment --- which allows
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programs on your local machine, and on selected remote systems,
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to act as clients on your "display server" (a display is
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one or more screens, a keyboard and a mouse and/or other
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pointing device).
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</blockquote>
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<blockquote>This is why you call the program that you run on your
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Linux system an "X server" --- because it provides display
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services to programs like '<tt>xterm</tt>' 'netscape' etc. The
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fact that most of these programs are usually running on the
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same host as the server is of no consequence to X. The
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X server communicates with all of its clients via sockets.
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</blockquote>
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<blockquote>Those are unix domain sockets ("<tt>s</tt>" special nodes on your file
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system --- usually under <tt>/tmp</tt>) for most localhost clients,
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internet domain sockets (TCP/IP networking) for most others).
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</blockquote>
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<blockquote>So, I suppose you can do "this" with X (that is, you could
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have an ISP co-located a server on the Internet, or you could
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have a dedicated connection fed into your home such that you
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could allow access to an X server from any client on the
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Internet. This would be horrible from a security standpoint
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--- but that's not something you've expressed any concern about.
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</blockquote>
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<blockquote>Shifting into "requirements analysis" mode we ask:
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</blockquote>
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<blockquote>What information, applications and resources
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to you want/need to make available to whom?
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</blockquote>
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<blockquote>... which leads to a more fundamental requirements question:
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</blockquote>
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<blockquote>Who are the involved parties? (You, and each person
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or class of persons to whom you would like to provide
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access to the aforementioned resources).
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</blockquote>
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<blockquote>You can use these two lists (resources, parties/customers)
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to build a table of "business relationships" (even if this
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isn't really a business, the principle applies --- you relate
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groups/users to the resources with verbs like "read" "write"
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"execute" "append/add" etc.
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</blockquote>
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<blockquote>When you have a clear understanding of these things you can
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evaluate and prioritize them. That is to say: you can
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place values on each of these relationships. You may find
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that many the items you listed are not really requirements
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--- but are really preferences or constraints. That's fine,
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keep them on the list.
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</blockquote>
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<blockquote>You could then look at your possible approaches (from the
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list above, and by doing additional research into ISP
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offerings in your area). All possible designs/plans which
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fit your requirements without violating any of your
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constraints form a "solution space." This may be an empty
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set (there may be not solutions to your set of requirements
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within your stated constraints). If there are multiple options
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a mapping of these overlaid on your preferences may find an
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optimal solution (that's why you prioritize/evaluate the
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preferences --- so you can do sums and scoring).
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</blockquote>
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<blockquote>At that point you'd be in a position to do a cost/benefit
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analysis. Undoubtedly costs/pricing formed some of your
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constraints. Presumably your preference (all other things
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being equal) would be to pay less. However, it is possible
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that you're costs will exceed perceived or potential benefits
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in such a way as to convince you to abandon the solution set
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(and a whole project).
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</blockquote>
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<blockquote>Actually all you said about your requirements was that
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you "need to know how to ...." --- hopefully you now "know";
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presumably you are, or were, considering actually setting
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something up and I'll have to guess beyond that.
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</blockquote>
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<blockquote>All I can guess about your requirements was that you
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want to be able to remotely get your mail, telnet to your
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machine, and update your .plan (finger info). You currently
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think you want to be able to do this "over the Internet."
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</blockquote>
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<blockquote>I'm not sure that you've really considered alternatives
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regarding this last one. If you connect a modem to your
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Linux box at home you can dial in and use it from anywhere
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that you can get at a modem and dial your home number. Unless
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you are a real globetrotter your home is probably a local
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call to you most of the time. In addition if your area
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has "Ricochet" or "<a href="http://www.metricom.com/">Metricom</a>"
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or <em>[Ricochet is the product sold or leased by Metricom. -- Heather]</em>
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any similar service it may be that you can get a wireless "modem"
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(provides a Hayes compatible AT command set and serial interface to your
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computer) with optional dial out service. (This allows you
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to use a "Ricochet" on your laptop, from the local coffee
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house or wherever you can get a signal to dial into your
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machine at home).
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</blockquote>
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<blockquote>Actually, oddly enough, this service has a strange idea
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of locality. I subscribe to it in the SF Bay Area. This
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lets me dial to any modem number in the 408, 415, 650, 510,
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and nearby area codes. It also allows me to dial to 800
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numbers. I can dial to these, toll free and without connect
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time charges from any where that Metricom's service extends.
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</blockquote>
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<blockquote>Thus I've dialed into my home computer from the Burbank
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Airport near L.A. and from a hotel lobby in Seattle while
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I was at a USENIX conference.
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</blockquote>
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<blockquote>Another thing that's not evident from your question is
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just what benefits you hope to get from all of this. Is
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it just "coolness" --- so you can do the same thing
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your friend did? If so, see if you can get an account
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on this other friend's machine. Is it convenience? Do
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you have any security concerns? How much is it worth do
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have this much "coolness" or convenience?
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</blockquote>
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<!-- end body -->
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<!--startcut ======================================================= -->
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<P> <hr> <P>
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<H5 align="center"><a href="http://www.linuxgazette.com/copying.html"
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>Copyright ©</a> 1998, James T. Dennis <BR>
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Published in <I>Linux Gazette</I> Issue 32 September 1998</H5>
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<P> <hr> <P>
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<!--::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::-->
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<table width="98%"><tr valign="center" align="center">
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<td rowspan="3"><A HREF="./lg_answer32.html"><IMG
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SRC="../gx/dennis/answernew.gif"
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ALT="[ Answer Guy Index ]"></A></td>
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<td><A HREF="tag_phreak.html">phreak</A>
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<td><A HREF="tag_abandon.html">abandon</A>
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<td><A HREF="tag_javaterm.html">javaterm</A>
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<td><A HREF="tag_BBS.html">BBS</A>
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<td><A HREF="tag_flaws.html">flaws</A>
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<td><A HREF="tag_doslinux.html">doslinux</A>
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<td><A HREF="tag_resume.html">resume</A>
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</tr><tr valign="center" align="center">
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<td><A HREF="tag_softwindows.html">softwindows</A>
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<td><A HREF="tag_convert.html">convert</A>
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<td><A HREF="tag_apache.html">apache</A>
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<td><A HREF="tag_emulate.html">emulate</A>
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<td><A HREF="tag_database.html">database</A>
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<td><A HREF="tag_distrib.html">distrib</A>
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<td><A HREF="tag_proxy.html">proxy</A>
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</tr><tr valign="center" align="center">
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<td><A HREF="tag_disable.html">disable</A>
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<td><A HREF="tag_DVI.html">DVI</A>
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<td><A HREF="tag_superblock.html">superblock</A>
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<td><A HREF="tag_serial.html">serial</A>
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<td><A HREF="tag_permission.html">permission</A>
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<td><A HREF="tag_detach.html">detach</A>
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<td><A HREF="tag_cdr.html">cdr</A>
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|
|
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</tr><tr valign="center" align="center">
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<td><A HREF="tag_rs422.html">rs422</A>
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<td><A HREF="tag_modem.html">modem</A>
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<td><A HREF="tag_notfound.html">notfound</A>
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||
|
<td><A HREF="tag_tuning.html">tuning</A>
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||
|
<td><A HREF="tag_libc5.html">libc5</A>
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<td><A HREF="tag_startup.html">startup</A>
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<td><A HREF="tag_clock.html">clock</A>
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<td><A HREF="tag_ping.html">ping</A>
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</tr><tr valign="center" align="center">
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<td><A HREF="tag_accounts.html">accounts</A>
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<td><A HREF="tag_lilo.html">lilo</A>
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<td><A HREF="tag_NDS.html">NDS</A>
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<td><A HREF="tag_95slow.html">95slow</A>
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<td><A HREF="tag_nonlinux.html">nonlinux</A>
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<td><A HREF="tag_progenv.html">progenv</A>
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<td><A HREF="tag_cluster.html">cluster</A>
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<td><A HREF="tag_ftpd.html">ftpd</A>
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</tr></table>
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<P> <hr> <P>
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ALT="[ Front Page ]"></A>
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</html>
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