Wikipedia:Reference desk/Archives/Computing/2009 March 31

= March 31 =

Quick 'n easy wireless router question
Can you use a 802.11n router with an 802.11g wireless card? I ask because I'm trying to help my aunt hook up a wireless internet connection. I know that two of her computers have wireless n airport cards, but one of her laptops only supports G. So will that old laptop work with an N router, assuming it's close enough? D a R kA g E 7 [Talk] 00:43, 31 March 2009 (UTC)


 * Yes. The two devices will operate at the maximum ability common to both.  In this case, they will use 802.11g protocols.  -- Tcncv (talk) 01:42, 31 March 2009 (UTC)


 * According to our article 802.11n, a "mixed-mode" network (at 2.4GHz) provides backwards compatibility with older 802.11 devices. Maximum throughput will be limited in such a configuration, but it will probably still be sufficient for most applications. (Note that you do *not* want 5GHz operation&mdash;you might have to configure the router specifically for 2.4GHz.) –  7 4   01:49, 31 March 2009 (UTC)


 * It's worth remembering that there's no such thing as a 802.11n router or wireless card yet as the standard has not been finalised. All current equipement is draft/prerelease n. From a look at the talk page, it sounds as if, at least as of mid 2008 that a lot of the draft equipement performs very poorly sometimes even worse then g equipement. As such, it may be better to just get a 802.11g router. Nil Einne (talk) 09:41, 31 March 2009 (UTC)
 * A lot, perhaps, but far from all. My Apple Airport Extreme (802.11 draft-n) gives me ~160 Mbit/s - way, way faster than the ~26 I got with the previous generation Airport Express (802.11g). Heck, it's fast enough that I only bother to plug in the 1 Gbps cable when I transfer more than 20GB, which doesn't happen very often. -- Aeluwas (talk) 17:33, 31 March 2009 (UTC)


 * Well 160 Mbit/s sounds good, but 26 Mbit/s doesn't so presuming it isn't bad environment it's perhaps also an indication that the Airport Express is a POS Nil Einne (talk) 11:38, 6 April 2009 (UTC)
 * Huh? No, it's not a POS (just outdated these days). See 802.11g - 26 Mbit/s is over the stated typical speed. It's also very close to 54/2 which rhymes well with the commonly stated "expect half the stated throughput". -- Aeluwas (talk) 19:35, 6 April 2009 (UTC)


 * I've heard that a lot of routers will default to G in a mixed-mode environment, effectively cutting the theoretical speed in half. You can get routers with multiple transmitters that will give you a separate G and N network, though. --  JSBillings  23:50, 31 March 2009 (UTC)

downloading
which is the efficient and powerfull downloading software that improves the downloading speed? —Preceding unsigned comment added by Jawhar.vt (talk • contribs) 11:15, 31 March 2009 (UTC)


 * There are many download managers. Check out List of download managers and Comparison of download managers.  --Sean 12:04, 31 March 2009 (UTC)


 * Note that while many of these will help with organizing downloads, you probably wont get dramatically improved speeds with ordinary HTTP downloads. Download managers that promise that are mostly snake oil. 195.58.125.53 (talk) 16:00, 31 March 2009 (UTC)


 * Anon is right, "downloading acceleration software" will probably not improve your downloading speed. Tempshill (talk) 16:30, 31 March 2009 (UTC)


 * Right. But some also seem to surmise otherwise, so also not grokking the first answer. -- Fullstop (talk) 21:23, 31 March 2009 (UTC)


 * How does an operating system change HTTP download speeds? I would like to meet these "some" that can prove it. Upgrading to high speed internet gets cheaper and more available every day. Livewireo (talk) 21:35, 31 March 2009 (UTC)
 * Switching operating systems will not improve your download speed, unless the new OS has better-configured network settings than the old one, in which case you could get the same effect by fixing the settings on the old OS. -- BenRG (talk) 17:34, 1 April 2009 (UTC)


 * The questioner is likely asking about dial-up services that offer high-speed downloads over dial-up. There is nothing special going on.  Assuming you download their "high speed program" on your end, the internet traffic is compressed (just a zip file) and sent to you.  You decompress it on your end.  The result is that you send less data over the slow telephone line but do more work on each end compressing and decompressing the data. --  k a i n a w &trade; 22:01, 31 March 2009 (UTC)


 * The very significant problem with those claims is that they must use 'lossless' compression - and as such, they cannot compress already-compressed data. Hence, if you are downloading JPEG photos or movies or MP3's (which are already close to optimally compressed) - these services don't (mathematically: cannot possibly) compress them significantly further.  The things they do get a speedup with is text - HTML files, that kind of thing.  But because an entire bookfull of text is less than a single large photo, this is speeding up the one thing that's already pretty much not a problem.  So unless you are in some very specialised situation where most of what you are reading is text with very few photos (like this Wikipedia page for example) - these compressing-dialup services are a con-trick. SteveBaker (talk) 02:48, 1 April 2009 (UTC)


 * I think many of these services lossily recompress inline images in web pages, which can make pages load substantially faster (if you don't mind the quality loss). I can't imagine they'd get much benefit from zip-type compression over dialup lines, since dialup modems have built-in compression already (V.44).


 * Also, JPEG is much farther from optimally compressed than you might think. PAQ8P and Stuffit can losslessly compress JPEG files by nearly 25%. You can get similar gains on compressed PDF, and probably on MP3, ZIP, JAR (Java) and SWF (Flash) as well. Those algorithms are extremely slow, though, so slow that I think a modern CPU would have trouble with realtime decompression even at dialup speeds. They're also patent-encumbered. I seriously doubt that any of the compressing-proxy services do this kind of compression. -- BenRG (talk) 17:34, 1 April 2009 (UTC)

3DS Max 9
Does anyone know how to put different colors onto a compound object in this software, thanks. BigDunc Talk 19:55, 31 March 2009 (UTC)