Wikipedia:Reference desk/Archives/Computing/2009 July 9

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July 9[edit]

Certified Ethical Hacker[edit]

I want to know about the Certification in Ethical Hacking?? what are its scope and limitations and from where it should be done so as to get the maximum result.. —Preceding unsigned comment added by 202.159.213.24 (talk) 04:19, 9 July 2009 (UTC)[reply]

If you are talking about this, I have to tell you, it looks kind of silly. I have never heard of this certification before, nor have I heard of the organization which offers this certification (though they list some credentials on their website). Why don't you just consider one of the technical skill certifications, like a Cisco Network Security Professional? I would place more stock in a reputable network security course (or better yet, a degree from an accredited college in computer or network engineering) than any sort of "ethical hacker certification." Ethics certification seems silly - it's more about your reputation, your professional conduct, and experience. As far as the technical knowledge, you would really do better to pursue a standard course in network engineering. Cisco's courses are very rigorous and (consequently) widely respected. Nimur (talk) 06:49, 9 July 2009 (UTC)[reply]
We have an article, Certified Ethical Hacker, for more information. Nimur (talk) 06:52, 9 July 2009 (UTC)[reply]

The ones that know don't tell, the ones that tell don't know. Ivtv (talk) 21:22, 9 July 2009 (UTC)[reply]

Expansion of information on the internet[edit]

How fast is the internet growth? Is the growth accelerating?--Quest09 (talk) 10:46, 9 July 2009 (UTC)[reply]

Google is your friend: yes and maybe. See internet statistics, internet growth charts. — QuantumEleven 10:52, 9 July 2009 (UTC)[reply]

connecting to my server[edit]

I have Uniform Server running with a small website, which I can access by typing "localhost" in to my browser. I would like for it to be accessible to a few friends too, but I don't know what to do. I've tried giving them my ip address to enter in their browsers but it hasn't worked. Anything else I can do? I am very new to computing so I would really appreciate if someone could explain in laymans terms. Thanks very much for your help.

Assuming that you have a residential connection through your ISP, you are likely behind a router/firewall. This will block users outside of your network from sending requests to your computer. Look into port forwarding and find the IP address of your computer by using Start->Run->command.com and using the ipconfig command. In your router's browser-based configuration, you should forward port 80 (TCP and maybe even UDP) to your server's IP internal IP address. Good luck! Freedomlinux (talk) 13:39, 9 July 2009 (UTC)[reply]
Thank you, but I'll still quite clueless as to what to do. When I type "ipconfig" into the run menu a black box flashes up on the screen for a fraction of a second then disappears. Have gone into my routers settings page and there is no option to forward ports. Is there any other way to do this, maybe a program I could download that would make this simple for me to do? Again, that you for the help
What you need to do is type "cmd" (without the quotes) into the Run box, and type ipconfig into that. That'll give you your IP address. Thanks, gENIUS101 16:57, 9 July 2009 (UTC)[reply]
Ok, I did that and it lists a load of ips, gateways and subnet mask. What now?
Find your gateway address and type it into your browser in a format like http://172.153.30.1 . This should open your router/other device configuration page. Every router works differently, so I would look up the method at [1] which is specific to your router. Be warned, however, that your ISP might prohibit you from running a public server and might even block common ports. So, you might have to have your users enter an address like http://your.external.ip.address:nonstandardport and have the port forwarding direct it to your.server.ip.address:80 . Freedomlinux (talk) 01:24, 10 July 2009 (UTC)[reply]

DVD closed captioning?[edit]

I just got The Man From Earth DVD. It doesn't have a subtitles, but there is closed-captioning. I can't get my DVD software to show it, although the DVD player connected to the TV can. 65.88.88.75 (talk) 16:47, 9 July 2009 (UTC)[reply]

if you are talking about computer software then you are missing the codec to display the subtitles. Google VLC player. It is free and will play it. Ivtv (talk) 21:30, 9 July 2009 (UTC)[reply]

I think it's actually closed-captioning that's included on the DVD. There's no subtitles option, and on a DVD player that's connected directly to the TV, nothing shows either. But on a DVD player connected to a VCR connected to a TV, I could get the CC. Weird. 98.14.223.143 (talk) 23:04, 11 July 2009 (UTC)[reply]

"Router", "network switch", "ethernet hub"[edit]

What is the difference between these from the home users point of view please? When or why would I need a router and not a network switch or vice versa? 78.146.251.48 (talk) 17:14, 9 July 2009 (UTC)[reply]

The articles router, network switch and ethernet hub will reveal all. The brief and imprecise version is that a router sends traffic to the right place, a switch is a kind of router hub with some performance and security advantages, and a hub is just a dumb device that forwards all traffic it gets on any line to all the other lines. --Sean 17:25, 9 July 2009 (UTC)[reply]
"What's the difference between a hub and a switch" is a classic job interview question at Cisco. Radia Perlman's answer is "a switch costs more". She's joking, but increasingly she's right. 87.113.26.43 (talk) 17:56, 9 July 2009 (UTC)[reply]
More seriouisly, a switch and a hub are level2 (ethernet) devices, and route traffic based on ethernet addresses. A router is a level3(ip) device, and routes traffic based on ip addresses. A switch is "smart", a hub "dumb", but even the cheapest hubs now do a lot of the things that only switches used to do. But saying a "switch is a kind of router" is entirely wrong. 87.113.26.43 (talk) 18:09, 9 July 2009 (UTC)[reply]
In your context, a router probably means a "residential gateway"; its primary use is the NAT capability: the ability to create a local network with multiple devices behind it but appear as one device to the outside network; this is necessary if, for example, your ISP only gives you only one IP at a time. A switch and a hub have very similar functionality -- they are both used to connect devices together on the same network (not separating networks as a router does); the difference is that a hub is dumb and when it receives a packet on one connection it broadcasts it along all the other connections; whereas a switch is smart and remembers where each device is, and only broadcasts it on the right connection; so when there are a large number of devices, a hub will be a lot slower than a switch because of collisions. Also, most routers you can buy today will have a switch built-in on the local side, so you will typically multiple local ports. --Spoon! (talk) 17:51, 9 July 2009 (UTC)[reply]

Windows explorer icon[edit]

I am on Windows XP Professional, and I want to set the "homepage" for Windows Explorer. I go to the shortcut properties, and right now the "Start in:" field reads "%SystemRoot%". I want it to open to My Computer, but I don't know what to type in that field. I'm sure someone here should be able to help me. Thanks, —Akrabbimtalk 19:22, 9 July 2009 (UTC)[reply]

You mean you want to change your desktop background picture? Ivtv (talk) 21:24, 9 July 2009 (UTC)[reply]
No, he's got a shortcut to Windows Explorer, and he wants it to open in My Computer, not c:\
I'm not at all sure that this is possible; creating a shortcut to "my computer" doesn't seem to be possible, and the fake-shortcut "My computer" in the XP menu system can't be copied. 87.113.26.43 (talk) 21:34, 9 July 2009 (UTC)[reply]

I am still confused on what the end user is requesting. If he is looking for a shortcut to the my computer icon, that is possible but im 100% certain that is not the issue. Windows explorer is a process, not an icon. whenever you browse your computer you are using windows explorer. What I think you want to do is change the shortcut to "my computer" to open something else besides listing your drives. That is possible. Ivtv (talk) 21:46, 9 July 2009 (UTC)[reply]

Change "Start in" to explorer.exe /e, ---— Gadget850 (Ed) talk 21:58, 9 July 2009 (UTC)[reply]

I've discovered a work around. After some google searching, and sorting through solutions for Vista, etc., I found a solution. You can set the default mode for opening a folder to be "exploring". Run regedit, go to HKEY_CLASSES_ROOT\Folder\shell\ and double click '(Default)'. In the 'Value data' type 'explore' (no quotes). —Akrabbimtalk 12:26, 10 July 2009 (UTC)[reply]

Resolved

Freeview (UK) - software updates?[edit]

Does Freeview transmit software updates for TVs? I know it sounds unlikely, but I swear my TV (which has an integrated freeview receiver) announced a couple of days ago that a software update was available & did I want to install it. So. Unlikely as it sounds, does Freeview transmit software updates for TVs? --Tagishsimon (talk) 22:06, 9 July 2009 (UTC)[reply]

Yes, software updates are transmitted over the engineering channel. Updates for certain boxes are transmitted for a specified time period, normally a day or 2. See [2] for more information. Clover345 (talk) 23:15, 9 July 2009 (UTC)[reply]
Wow. Thanks. Who'd have thought? --Tagishsimon (talk) 23:22, 9 July 2009 (UTC)[reply]
Freeview NZ does the same thing. I can even see the channel with my DVB-T card. Of course subscription based satellite services have been doing the same thing for a long while (and I presume cable in those countries that have it). It makes sense of course, it's an advantage to be able to update the device, e.g. for new channels, changes in the MHEG-5 format etc and telling consumes the device needs a network or telephone connection is not going to be endearing. And the channels are digital data, there's no reason you can't use them to send updates. Nil Einne (talk) 16:35, 10 July 2009 (UTC)[reply]

GetTextExtentPoint32[edit]

I am trying to use Win32 API's GetTextExtentPoint32 to determine the extent (in pixels) of a on-screen string. It appears to be working as it should, but it includes some (normal) space above and belove the "normal" characters (see extent.png @ privat.rejbrand.se). For my application, I would need to determine the exact height of the written (capital) characters (in my *.png image, it would be the height of the letters "H" and "E"), without any additional spacing. How can I get this information (without first drawing the text, and then manually examining the resulting bitmap...)? --Andreas Rejbrand (talk) 23:43, 9 July 2009 (UTC)[reply]

I have found the following method to work:
 GetTextMetrics(DC, m);
 y0 := m.tmInternalLeading;
 y1 := m.tmHeight - m.tmDescent - m.tmExternalLeading;
If you use TextOut from the point (x, y), the text occupies the vertical region [y + y0, y + y1]; thus, the height is y1 - y0. --Andreas Rejbrand (talk) 23:56, 10 July 2009 (UTC)[reply]
Resolved