Wikipedia:Reference desk/Archives/Computing/2008 June 8

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June 8

Program to save audio (micro and headphone)

Do you know a free one? GoingOnTracks (talk) 00:25, 8 June 2008 (UTC)

Audacity. Its audacious! It is free as in free speech AND as in free beer. It records audio and much more. Cheers, Kushal (talk) 01:19, 8 June 2008 (UTC)

Thank you. I'll try it.GoingOnTracks (talk) 02:23, 8 June 2008 (UTC)

You are most welcome. Please come back if you have any more questions. Kushal (talk) 09:36, 9 June 2008 (UTC)

You can use Windows' sndrec32, though it's not as good as Audacity. In a pinch, it gets the job done. JeremyMcCracken (talk) (contribs) 02:27, 12 June 2008 (UTC)

awesome mozilla tools

I was checking out stuff like this and this.. I assume these are php apps or something.. where can I download them? .froth. (talk) 02:58, 8 June 2008 (UTC)

The first one is "User Agent Switcher", a Firefox extension. Open [1] and click "Add to Firefox". --grawity 12:28, 8 June 2008 (UTC)

Uh no I mean the app that lets you browse the source of packages.. not the package itself. .froth. (talk) 19:05, 8 June 2008 (UTC)

Oh... I think the filebrowser is just another page, just like any other part of the website, only interactive. So you should ask the website owners/authors. --grawity 11:07, 9 June 2008 (UTC)

Messenger: Personal Messages

Hello. Is there an automatic feature where I can have a personal message when I am signed into Windows Live Messenger (e.g. Hello) and a different one when I am signed out (e.g. I'll respond to your offline message ASAP)? Thanks in advance. --Mayfare (talk) 04:04, 8 June 2008 (UTC)

June calendar of events

Respected Sir

I have observed that a very important event like 'World Environment Day' that is observed all over the world is missing from your list of events from June calendar which is published on the right side of your main page.

Kindly ensure such events are covered so that many readers who visit your site will be enlightened.

Please treat this as a suggestion.

Regards

Lion. Dr. Francis P S Rajan —Preceding unsigned comment added by 59.93.69.190 (talk) 07:38, 8 June 2008 (UTC)

Well, we do have an article on World Environment Day, and it is in the list of "holidays and observances" at June 5#Holidays and observances. And I think annual events aren't usually featured on the Main Page - it only lists one-off items of international news and significant anniversairies. But there is a discussion page for the Main Page (and a whole lot of suggestion pages linked from that) if you want to raise the issue there. Gandalf61 (talk) 08:33, 8 June 2008 (UTC)

This appears on the Main Page for the 5 June each year, see Wikipedia:Selected_anniversaries/June. --h2g2bob (talk) 17:59, 8 June 2008 (UTC)

Why is frequency division used in microprocessors?

We had 8085 in our current semester, where we learnt that even though the uP itself operates on 3MHz, we use a crystal oscillator of 6MHz. This is so that we can divide the latter by two and provide a 50% duty cycle clock which the microprocessor requires. Could someone please explain me this concept in detail? What is the "duty cycle" of a crystal oscillator? If the microprocessor requires a square wave, doesn't it already have 50% "duty cycle"?

Thanks. --RohanDhruva (talk) 09:58, 8 June 2008 (UTC)

There is probably just some redundancy in the material you were given. It's no more wrong than saying a square with all sides equal, so it's probably just for learning purposes. And yes, if the microprocessor requires a square wave, the square wave by definition would already have a 50% duty cycle. It is slightly possible they meant to say rectangular wave with a 50% duty cycle, which would then not be redundant. And connecting a 6MHz oscillator to the 8085 is required for the 3MHz operation, because there's a built-in divider in the 8085 (see our article on the Intel 8085). As extra info, modern processors generally step up the crystal instead of down, so in modern chipsets, you would use a 3MHz crystal for a 24MHz chip, or something of the sort. Hope that helps. --Wirbelwindヴィルヴェルヴィント (talk) 03:20, 9 June 2008 (UTC)

Thanks Wirbelwind, but it still doesn't answer my question. What I wanted to know is why i that internal frequency divider used? What is the purpose? BTW, thanks for the info in newer mucroposessors - I was wondering how one could have a 2.8GHz crystal ;) --RohanDhruva (talk) 06:59, 9 June 2008 (UTC)

Probably more different clock rates are needed, so that the faster clock is needed too for some purpose, such as accessing memory or IO bus. Graeme Bartlett (talk) 21:48, 9 June 2008 (UTC)

TrueCrypt reliability

How reliable are cryptographic programs like TrueCrypt? I mean reliable in the sense that I always be able to access my data, but nobody else. GoingOnTracks (talk) 12:55, 8 June 2008 (UTC)

Every chain is as strong as its weakest link. So no program like that is a one-stop solution—you need to be protected from malware, phishing, etc., as well as physical security of the machine, not to mention safe computing habits (not executing unknown code on a regular basis, keeping up with security updates to software and the OS, choosing strong passwords and not using the same one on every site, etc.), or else all the encryption in the world isn't going to mean a thing (just like the biggest, strongest door lock in the world is defeated by a ground-floor window left open).

As for the level of encryption itself—it means the NSA's standards, so it looks pretty reliable to me. But again, that's only one piece of the overall puzzle. At Los Alamos during the Manhattan Project, they had fences, armed guards, help from the FBI and G2, were sited in a remote location, used code-words, compartmentalization of information, etc. etc., and it was all for really nothing because in the end, one high-placed guy had never been properly screened for his security clearance by the British and he walked out the door with everything they came up with and gave it to the Soviets. --98.217.8.46 (talk) 14:56, 8 June 2008 (UTC)

Yes, this is exactly right. Assuming you have a password that has 256 bits of random entropy (i.e. it is as strong as the key for the cipher itself), the encryption itself is completely bullet-proof: if you put all the computers in the world together to crack the password it would still take billions and billions more time than the age of the universe.

However, that is not the only piece of the puzzle. In very short terms, if you can have a password that is very long, impossible to get, not written down or shared with anyone and your computer hasn't been compromised, then you are pretty much guaranteed that you have encrypted files that not even the NSA can open up. Unless they torture you and stuff. Which would be bad for a whole bunch of other reasons. Although, if you use the "hidden drive" feature of TrueCrypt, you can get around even that. Isn't modern cryptography wonderful :) 83.250.202.36 (talk) 22:05, 8 June 2008 (UTC)

Ok, so far for the security of the encryption against a third party. But how about the possibility that TrueCrypt scrambles my data and they can't be recovered anymore, even if I get the right password? Or is the program so stable and reliable that it always decrypts and encrypts right? GoingOnTracks (talk) 00:02, 9 June 2008 (UTC)

The danger is less that the software will scramble your data, but that in the process of reading/writing the drive, data corruption will occur as it sometimes does with all harddrives. However in an encrypted drive, one bit of corrupt data will probably throw the entire ciphertext block out of whack—meaning that instead of just losing 1 bit, you lose 128 bits. (Source) So it's not a trivial issue—if your drive starts to get really wonky, you're going to suffer more with an encrypted drive than you would with an uncrypted one, because of the extra layer of data that encryption throws onto things and the fact that it won't decrypt correctly if the checksums don't match up and so forth. The problem isn't with the program, per se, it's with any program that encrypts anything—if you have harddrive problems, you're going to have them in spades. (Do you really need to encrypt your whole drive? Couldn't you just encrypt, say, your e-mail, your porn, and your warez? ;-) Something like that would drastically reduce the danger, as you'll probably notice the drive problems in your unencrypted harddrive than you would in the encrypted areas.) --98.217.8.46 (talk) 01:33, 9 June 2008 (UTC)

I don't think it's worth worrying about this kind of thing. If your hard drive is flipping bits then you have bigger things to worry about, like imminent total drive failure. A somewhat bigger concern is that damage to the volume header will render the whole volume unreadable. Because of this you may want to make a backup copy of the volume header and store it in a safe place, as described in the documentation. But the most serious threat to TrueCrypt-encrypted data is that you might forget the password. -- BenRG (talk) 13:01, 9 June 2008 (UTC)

Broken WNR834b v1

Hello all,

hopefully one of you can help me: after an odyssey on the Netgear WNR834B v1 router firmwares (original, DD-WRT mini, DD-WRT std, back to original), I cannot access the web pages, I get wrong passwords; but I tried through the standard pwd, mine and the DD-WRT password; even resetting the config with the HW switch was not successful.

88.217.62.34 (talk) 15:08, 8 June 2008 (UTC)

MediaWiki

What does this mean, which is coming up on my wiki:

Database error
A database query syntax error has occurred. This may indicate a bug in the software. The last attempted database query was:

    (SQL query hidden)

from within function "efUpdateCheckUserData". MySQL returned error "1146: Table 'simlandw_wiki.cu_changes' doesn't exist (localhost)".

How do I fix it? StewieGriffin! • Talk Sign 17:55, 8 June 2008 (UTC)

Have you recently upgraded the codebase? If yes, run the update script. If not, delete the Checkuser extension. 88.217.61.83 (talk) 04:39, 9 June 2008 (UTC)

Music Programs

It seems Reason is like a more inclusive program, let's say, compared to a Digital audio workstation like Pro Tools. Are there any other programs like Reason, and if so, could you provide a list? My other question is if there are "higher-level" programs", than Reason, as it seems like Reason can do everything Pro Tools can do, and I'm wondering if there are any programs that are "higher-in-level" than Reason, and if so, could you provide a list. Thank you!68.148.164.166 (talk) 18:23, 6 June 2008 (UTC)

I think you need to clarify what 'inclusive' means. If you want software that contains recordings for you and be 'inclusive' then Acid could be good. Ableton has ALOT of options, and Logic can do everything Pro Tools can too. Please clarify inclusive for a more precise answer. 86.140.7.114 (talk) 00:26, 8 June 2008 (UTC)

Pro Tools only mixes and records, but Reason mixes, records, reverberates, etc. etc.. That's what I mean by inclusitivity.68.148.164.166 (talk) 18:25, 8 June 2008 (UTC)

Its still not clear what you mean. Pro Tools can add reverberation via plug ins. Are you after the software which does the most things?86.140.7.114 (talk) 19:19, 8 June 2008 (UTC)

Yes, I'm after the software which does the most things. Hmmm, what's the difference between Pro Tools and Reason? And what exactly is a rack?68.148.164.166 (talk) 20:53, 9 June 2008 (UTC)

What's wrong with Audacity? Kushal (talk) 09:33, 9 June 2008 (UTC)

Audacity is free, but Adobe Audition and Sony ACID have more features. Acid is easier to use, but has less features than Audition.--Hello. I'm new here, but I'm sure I can help out. (talk) 10:00, 9 June 2008 (UTC)

Time Machine and Airport Extreme

Time Machine didn't initially support backups to Airport Extreme discs, but it does now. Does it backup to both the new "N" generation and the older "g" ones, or just "N"? And do you plug the disc into the ethernet or the USB port in it? Thanks for your help.--78.148.200.171 (talk) 21:18, 8 June 2008 (UTC)

The old Airport is round, the new one is rectangular.89.242.194.227 (talk) 17:36, 9 June 2008 (UTC)