Wikipedia:Reference desk/Archives/Computing/2006 August 11

P2P
I am considering alternatives to my current P2P network, and I am curious as to what you, my fellow Wikipedians, would recommend. I will not disclose my current P2P network, as I don't want that to influence your answers. Just tell me which one you would get, and why. I have already had a look-see at this. Also, freeware please :D. Any responses are appreciated. If it matters, I am using a Windows XP. 71.98.15.40 00:10, 11 August 2006 (UTC)


 * BitTorrent Jon513 00:52, 11 August 2006 (UTC)

Netsend
What is it? Is it like some kind of messeging command to messege other people on the same network? Wizrdwarts (T|C|E) 00:16, 11 August 2006 (UTC)
 * Yes, that's pretty exactly what it is. See Microsoft's website for more information. --Canley 02:07, 11 August 2006 (UTC)
 * Your answer was in the title of the second result on google and the 4th result is the link to microsoft --mboverload @ 02:49, 11 August 2006 (UTC)

HTML vs. XHTML
If I had no prior knowledge of either, and I wanted to learn how to code, which one should I learn? Which one is generally perceived as easier to learn? Should I learn both? Thanks for the advice. --71.98.15.40 04:10, 11 August 2006 (UTC)
 * XHTML is backwards compatible with HTML. I don't think either is really "easier" they just use slightly different rules.  Anyway, I'd go for HTML but only because I don't want to close tags all the time. --mboverload @  04:19, 11 August 2006 (UTC)
 * All right. Thanks for the advice! Wish me luck. --71.98.15.40 04:42, 11 August 2006 (UTC)


 * HTML is dead. However, its ghost lingers, so even though you really must learn XHTML 1.1 you need to consult the HTML 4.01 reference to do so. The differences are not great, but they are vital. Three aspects of XHTML of special interest are
 * You must observe XML rules. In particular,
 * the case of tags and attributes matters
 * ► all the HTML tags must be lower case
 * ► all attribute names must be lower case
 * nesting must be correct
 * ► an opening tag like &lt;p&gt; (for paragraph) demands a closing &lt;/p&gt; tag
 * ► an "empty" tag like &lt;hr&gt; (for horizontal rule) must be written &lt;hr /&gt;
 * Deprecated tags and attributes of HTML 4.01 have been dropped.
 * Appearance should be described using CSS styling rules, with markup tags used solely to structure the content.
 * It's easier to learn good habits to begin with than to unlearn bad habits. Going forward, you must close tags, so get used to it already.
 * Once you're comfortable with the basic syntax of XML, you can learn to use and appreciate combined markup like the W3C profile of 2002 combining XHTML, MathML, and SVG. --KSmrqT 06:59, 11 August 2006 (UTC)


 * If I were in your position I'd learn XHTML. XHTML will soon completely replace HTML and it's not really much more difficult - you just have to do everything that's considered 'good practice' in HTML.


 * Thanks for the feedback, guys. I really appreciate it. 71.98.16.96 17:36, 11 August 2006 (UTC)


 * Though despite being officially deprecated, it is not as if browsers are going to stop supporting HTML anytime soon, though over time more and more will support XHTML. I mean, most of the internet is currently "deprecated" according to W3C. --Fastfission 13:53, 12 August 2006 (UTC)

Garageband for Windows
Is there a version of garageband available for Windows? If this exists(which I doubt) where could I download or buy it? If it does not exist are there any similar music makers for windows? Thank you.
 * What do you get when you put up to 2GHz of pure Intel Core Duo power, an iSight camera, Front Row, iLife ’06, and a 13-inch glossy widescreen display into a sleek case? More than you thought possible for less than you thought possible. Meet MacBook, starting at $1099. =D --mboverload @ 05:01, 11 August 2006 (UTC)
 * Wikipedia is not a place for you to advertise. Besides, Macs are horribly overpriced.--Frenchman113 on wheels! 20:37, 11 August 2006 (UTC)
 * I wasn't advertising, and you can't say something is over priced when it's the only thing that will run garageband. --mboverload @  01:22, 12 August 2006 (UTC)
 * Considering garageband is not that incredible a piece of software and something along the lines of cubase runs much better, has more features and sounds better in the end, your argument is entirely invalid.

I appreciate your time and thought but I am looking for something for windows that I can use in the more near future.

Is there no better answer to my question?

My personal suggestion is but if you look around their website they also have free software. Funnyfarmofdoom 06:56, 11 August 2006 (UTC)

Thank you
 * The closest equivalent to Garageband I can think of would be EJay. Sum0 20:01, 12 August 2006 (UTC)

strange svchost.exe...
Hi,

Recently my computer slowed down. When I use Task Manager to check what is causing it, it turns out that svchost.exe with SYSTEM as the user of it, is using 100% of CPU! I killed it with End Process, and the services that associate with it(e.g. sound) are gone. I restarted the computer, and svchost.exe is again using 100% of CPU. I waited patiently. 5 minutes later it cooled down and I can use the computer normally.

I used ZoneAlarm to block off its internet access, and it turns out that it is connecting to quite a lot of random IP addresses, and when I WhoIs some of the addresses, companies from Canada, US, and China turned out to own those IP addresses.

Could this be a virus like Welchia? And is svchost.exe connecting to those IP addresses normal?

Thanks in advance!

--inky 07:57, 11 August 2006 (UTC)


 * svchost itself is a basic part of windows - it's just a simple wrapper program that allows other programs to run as windows services. So svchost itself won't make network connections, least of all to china. But anything (with admin priviliges) can install themselves as windows services using svchost.  This does sound like a bad program may have installed itself as a service - try using a spyware removal progam. Middenface 08:20, 11 August 2006 (UTC)


 * My first reaction would be just to blame microsoft (accounts for the cpu usage) but connecting to lots of ip addresses sounds like you've got a virus.


 * Thanks... I'll use Windows Defender. --inky 09:58, 11 August 2006 (UTC)


 * The Welchia worm runs as or under svchost.exe. Thankfully, it is benign and if you have a fully updated copy of Windows, you shouldn't have it. My copy of svchost makes all sorts of connections; WHOISing the IP addresses shows that they belong to my ISP, or my Router, or other things it should be connecting to. Don't worry too much about Welchia, although it may be another virus disguised as svchost. With those kinds of connections, it sounds like a spambot or adware. Windows Defender is a good choice, i've found it rather effective. CaptainVindaloo t c e 14:12, 11 August 2006 (UTC)


 * On Windows XP, you can find out what's running via svchost.exe by taking the following steps -
 * 1 - Click Start on the Windows taskbar, and then click Run.
 * 2 - In the Open box, type CMD, and then press ENTER.
 * 3 - Type Tasklist /SVC, and then press ENTER.
 * That is from Microsoft, by way of this page. There are steps given there for Windows 2000 as well.  This PC World article recommends using the freeware program Process Explorer.  --LarryMac 14:27, 11 August 2006 (UTC)


 * Note that the Microsoft web page mentioned by LarryMac says it is for XP Pro. I found that it only works if you are logged in with an account that has administrator privileges. --Gerry Ashton 21:54, 11 August 2006 (UTC)

I get several copies of svchost running on my Windows 2000 system, frequently. The computer churns like mad, then after a while, they all go away and I can actually get in and do some work, but in the meantime, the system crawls. Any ideas? User:Zoe|(talk) 02:04, 12 August 2006 (UTC)


 * Some virus scanners do scans inside svchost, but most likely your seeing runs of the windows indexing service. Middenface 02:10, 12 August 2006 (UTC)

Wikipedia sidebar redesign problems
We are redesigning the sidebar that appears on every page of Wikipedia. However, we've run into some implementation problems. The biggest one is that we can't put a new menu below the search box. But putting it above the search box forces the search box further down the page than is desirable. We need capable (php) programmers to figure out a way. Please join us at Wikipedia talk:Village pump (proposals)/Sidebar redesign. --Nexus Seven 11:40, 11 August 2006 (UTC)

Screenshot Video Software
Is there any free screenshot video softwar that is free for download?--203.124.2.16 14:02, 11 August 2006 (UTC)
 * See screenshot, in particular the "Hardware overlays" section. Google is also your friend, search for something like video screenshot. Weregerbil 15:41, 11 August 2006 (UTC)


 * If you're looking for what I think you're looking for (Your diction's a little shaky, to me.), and using Wi***ws, WME (Windows Media Encoder) is great. --Brie Aleida


 * Ah, now I see the ambiguity. Do you want to take a screenshot of a video, or make a video of what you do on your screen? Or something else? I'm now starting to guess "make a video". Weregerbil 18:55, 11 August 2006 (UTC)


 * If that's the goal, there's something called Wish that's free and really good for that, but it's impossible to google for. Darn. grendel|khan 01:05, 13 August 2006 (UTC)

Broadband Servers
I could do with some help if anybody could help me I've only just started looking into braodband and I was wondering are there buildings out there with servers housed in them where the internet, for broadband users,is distributed like a network? If anybody has any ideas about Broadband and any information relating to the networks used etc could you please email me with any information and/or links to websites where such information can be accessed.

Gratefully yours

Aaron Hardman

(email address is removed for your protection, please read the instructions at the top of the page)

I/O
What is the significance of on-off switches (such as those on computers) being labeled "I" for one option and "O" for another? In the disambig for I/O, the only computer-related topic was "input-output," so I don't think this is it. JianLi 16:12, 11 August 2006 (UTC)


 * It is more likely one and zero - numbers, not letters. In electronic logic and computing, 1 tends to mean On and 0 tends to mean Off. --Kainaw (talk) 16:57, 11 August 2006 (UTC)


 * I just remembered a conversation a long time ago where a person thought it was strange that the letters I and O were used. The reasoning is that in German, on and off begin with I and O.  It was pointed out that the common words for On and Off in German computer-speak do not begin with I and O.  I don't know German, so I don't remember what they were.  However, it was later suggested that + and - be used.  But, you'd end up with Chinese wondering why the number 10 means On and the number 1 means off. --Kainaw (talk) 19:47, 11 August 2006 (UTC)


 * Thanks, that makes sense. And the part about the + and - in Chinese is interesting :) JianLi 01:18, 12 August 2006 (UTC)


 * German for On is Ein and German for Off is Aus. J I P  | Talk 10:51, 12 August 2006 (UTC)


 * I can't recall where I read it, but I believe they are meant to be a vertical line and a circle, not 1 and 0 nor I and O. I think it was in some standards publication in the UK. -- SGBailey 22:54, 12 August 2006 (UTC)


 * What I usually see now is either a back-and-forth switch with 0 and - or 0 and |, or in the case of an in-and-out switch, a circle with a hole in the top and a line coming out, a little like a rotated Q. Black Carrot 22:05, 15 August 2006 (UTC)


 * I always thought it was a logical diagram. O is open, therefore off. I is a straight line, therefore closed. I may even have the arrangement backwards, that's what I always assumed, though. kalemika

ftp browsers
Why can my firefox log on to ftp://ftp.wayne.edu/pub/gnu/ anonymously but my ie gets a login screen and I can't get on?


 * Because IE FTP Handling is far from great? Benbread 22:50, 11 August 2006 (UTC)


 * It works for me using IE 6.0. --Gerry Ashton 22:59, 11 August 2006 (UTC)


 * Try using the login "anonymous" and any random junk as the password (which is what Firefox is doing behind the scenes; IIRC it uses "mozilla@" as the password, because some servers require a specific password format). --cesarb 23:24, 12 August 2006 (UTC)

Fickle Network
I've got a network set up like this: 192.168.1.51       192.168.1.1                              192.168.2.2 DSL---ROUTER  ))))))))))))))  ((((((((((((((  CLIENTPC3 192.168.2.10 |    |          |     |     PC2     ---PC1 192.168.1.53  192.168.1.52


 * CLIENT = a linksys WRT54G running with dd-wrt micro in client mode
 * ROUTER = linksys WRT54G running standard linksys firmware
 * --- = Ethernet connection
 * ))(( = Wirless connection

Here are the observations:
 * -all subnets are 255.255.255.0
 * -PC3 can ping PC1 and PC2, it can open their shared folders
 * -PC3 can access the internet
 * -PC1 and PC2 can ping each other and open each other's shared folders
 * -PC1 and PC2 cannot ping or open PC3's shared folders.
 * -the command "net view" on PC3 shows only PC3.

My question:

How do I get PC1 and PC2 to access PC3's shared folders and ping PC3?

Thanks.


 * Let me get this right... You have one router with 2 PCs and a router plugged into it. The 3rd PC is plugged into the extra router.  Right?  You realize that the router has a firewall in it.  You have to explicitly forward the ports on the router to PC3 to see through it. --Kainaw (talk) 19:35, 11 August 2006 (UTC)


 * so you're saying if I forward every single port from 192.168.1.1 to 192.168.1.51 PC1+PC2 should be able to see PC3..?
 * hmm...didn't seem to work..


 * Close, but not correct. You are thinking about it wrong.  The routers are also firewalls.  To talk to a computer that is plugged into a firewall, you have to punch a hole through the firewall.  So, you punched holes through one router, but the computer is plugged into the other one.  How is that supposed to work?  You also have another problem - the routers will want to have the same IP address.  Are you sure that they are not both trying to use 192.169.1.1? --Kainaw (talk) 03:06, 13 August 2006 (UTC)
 * I just don't get how I can use the internet but I can't contact the router that's giving me the internet...(even though I listed it specifically as the DNS server)
 * And no, the second router I specifically set to 192.168.1.2 so as not to interfere.
 * These networks are so damn fickle!! Wjlkgnsfb 06:23, 13 August 2006 (UTC)


 * Lets just assume you ONLY want to get through to port 10 (you don't want for forward EVERY port). You need to forward 192.168.1.1:10 to 192.168.1.2:10.  Why?  the second rounter is behind the first router's firewall.  That is just half the battle.  Now, you need to forward 192.168.1.2:10 to PC3:10 (whatever the IP of PC3 is).  Why?  PC3 is behind the second router's firewall.  The will allow someone to go through the main firewall, through the second one, and to the PC.  But, you have to remember that you cannot forward a port to more than one IP.  So, you cannot forward 192.168.1.1:10 to both the second router and PC1 and PC2 all at the same time.  The networks aren't fickle - they are just firewalls. --Kainaw (talk) 13:26, 13 August 2006 (UTC)


 * Kainaw provided a great explanation, but incase that doesn't work either, try making PC3 the second routers (CLIENT, was it?) DMZ (this is a configuration that basically says "Forward everything to me, unless a rule specifically says not to"). See DMZ host. Since there's only one computer on it, this shouldn't be a problem and since it doesn't connect to the internet directly, there is no loss in security. I haven't experimented with this alot (don't have two routers), so I could be wrong, but if you do this, then the router will basically act as if it is PC3 (so that if you wanted to make a connection to it you would use the routers address instead of the computers and it would work just like if you made a connection to the computer itself). This should make windows file sharing, and everything else, work just fine. Oskar 22:11, 13 August 2006 (UTC)

making ascii diagrams
How do I get my network diagram (see above question) to show up just like it shows up in the edit mode?


 * Put a space at the beginning of each line. --LarryMac 19:07, 11 August 2006 (UTC)


 * Or, put &lt;pre&gt; in front of it and &lt;/pre&gt; after it. --Kainaw (talk) 19:33, 11 August 2006 (UTC)

Bittorrent Performance
When I use bittorrent I find I get the greatest download speeds (200-500kbps) when I have 5+ torrents going at a time and my max_upload set to below 20kbps (I set it to 10kbps usually). This contradicts what I've read here on wikipedia which says something like downloading is proportional to uploading. My connection (comcast cable) allows about 50kbps up if I don't throttle but then my download seems to hover around 100kbps. Am I a fluke? Is there metadata consuming bandwidth that isn't reported? I use Azureus and BitComet and it happens with both. - Peregrinefisher 03:17, 12 August 2006 (UTC)
 * I've noticed this as well. My guess would be that there's a significant amount of bandwidth used keeping track of the other peers -- just a guess. I have an upload speed of 24kB/sec, and if I cap my upload to 10kB/sec I get significantly faster speeds than if I use 18 or 20. Taiq 12:56, 12 August 2006 (UTC)
 * I used to see this effect when I had a cable modem; I don't see it on ADSL. My guess was that there were collisions in incoming vs outgoing packets and that reduced bandwidth. At some point there is a sweet spot: enough upload to keep peers happy, not too much to get excessive collisions. Weregerbil 13:15, 12 August 2006 (UTC)


 * This happens because the uplink is used not only for the upload packets, but also for the acknowledge packets from the TCP connections being used for downloading. If you use too much of your bandwidth for uploading, some of the ACK packets are lost or delayed, leading to spurious transmissions from the other side (which wastes bandwidth), and most importantly leading the congestion avoidance algorithms to think there's congestion on your link (and thus reduce the transmission speed, hoping to clear the congestion). One solution is to reduce the upload bandwidth to a point where the router queues are mostly empty; another solution is to prioritize ACK packets over data packets (however, this can be done only in the router immediately before the bottleneck, using something like wondershaper; if you don't control that router, you can artificially introduce a bottleneck on a machine you control and do the prioritizing there). --cesarb 23:19, 12 August 2006 (UTC)