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April 8

History of X.25 packet switched networks

I can't figure out from [1] whether there were any companies offering X.25-style data communications prior to 1976. Can anyone find a history that says when such commercial datacom services were available? Did the "Joint Working Party on New Data Networks, which was created by the IVth Plenary Assembly of the CCITT in 1968" result in anything commercial? 71.215.74.243 (talk) 06:10, 8 April 2012 (UTC)[reply]

Some like Compuserve were around then but also used propriatory network protocols. Back in those early days asynchronous communication, ie characters with start and stop bits were used, rather than packet switching. The main connections were direct from terminal to computer, and only later multiplexors came into being so that you did not have to make a phone call across the country to the computer. Standard speeds were 45 50 75 bits per second, later stretching out 300 bits per second. The telecom companies mostly offered point to point data services, if you did not want to use a modem on a phone line. Graeme Bartlett (talk) 10:12, 8 April 2012 (UTC)[reply]

Thank you. I see now that the CCITT JWP on NDN was mostly circuit switched technology prior to 1976. 71.215.74.243 (talk) 23:12, 8 April 2012 (UTC)[reply]

Pictures spreading through Facebook showing people in need

Everytime I look at Facebook, I frequently see these sad and touching images that people ask to share. For example, one says "This baby has cancer. Like of you wished cancer didn't exist ! :(" while another says "this is so sad giving drugs to babys :'( 1 Like = 1 prayer for each baby that died from drug abuse. :'/" which is a picture of a picture of a baby in pink clothes in a coffin, which is found on a celebrity's Facebook page (I am not subscribed to him, but some of my friends are). But, are these pictures real, are the people really sharing them, or is this just some chain post stuff? If they are real, I'm sure their sharing intentions are good, but are their good intentions being abused? Narutolovehinata5 ^tccsdnew 06:43, 8 April 2012 (UTC)[reply]

They're obviously hoaxes or just some sort of schadenfreude at the expense of the person in question. Even if they claim that Facebook will be giving a portion for the benefit of the supposed beneficiaries, the way these shared posts are circulated reeks of a typical chain hoax. Blake Gripling (talk) 09:00, 8 April 2012 (UTC)[reply]

They're chain posts. Check Snopes.com for any one of them. The one I've been seeing lately is the burned baby and the text usually says something about someone giving money to help the baby for each share. But it's bogus. See this article for more on it. Dismas|^(talk) 09:32, 8 April 2012 (UTC)[reply]

However, the ones I see don't say anything about donations. Instead, they say something like "share if you love your mother", or "share if you are touched". Narutolovehinata5 ^tccsdnew 09:52, 8 April 2012 (UTC)[reply]

Probably false. Slacktivism in any case. --Mr.98 (talk) 12:48, 8 April 2012 (UTC)[reply]

Just another way to waste your time on the Internet. HiLo48 (talk) 12:56, 8 April 2012 (UTC)[reply]

Flashback trojan

Is there any way that I can check, and clean if necessary, my Macs for the Flashback trojan without having to install any anti-virus software? Will updating Java and the OS with the latest patches sanitize an infected system? Dismas|^(talk) 09:35, 8 April 2012 (UTC)[reply]

An article in Ars Technica suggests typing the following commands in Terminal if you'd like to check for any infections:

    defaults read ~/.MacOSX/environment DYLD_INSERT_LIBRARIES

    defaults read /Applications/Safari.app/Contents/Info LSEnvironment

    defaults read /Applications/Firefox.app/Contents/Info LSEnvironment

If Terminal tells you that the stuff you queried doesn't exist, then you're good to go. As for updates, well, yeah, you should do that especially if you determined that your Mac's clean. And you should install an antivirus, as, well, you'll never know. Blake Gripling (talk) 13:46, 8 April 2012 (UTC)[reply]

newly created torrent won't seed

I've been using bittorent software and torrents for several years, but have never tried creating my own. I need to create a torrent in order to share a single large private file with a friend. I've followed a number of tutorials and each time I have the same problem. I select the file, add a public tracker, create and save, and then the torrent is added to my queue. It says "downloading" and does nothing. I stop it, change the download location to the same location as the file, and then restart it. According to the advice I've read, it should then recognise the file and build it, say download is complete, and start seeding. Why won't it get to this seeding stage? It doesn't get past "downloading", where it stays stuck at 0. Any ideas what I'm doing wrong? I'm on a Mac, Lion OS, and am using BitTorrent. Katherine.J.W. (talk) 13:39, 8 April 2012 (UTC)[reply]

Have you tried using uTorrent instead? Blake Gripling (talk) 13:47, 8 April 2012 (UTC)[reply]

Yes. It appears to be exactly the same program, with different branding. Katherine.J.W. (talk) 13:52, 8 April 2012 (UTC)[reply]

Nevermind, I got it to work with uTorrent, though I'd like to understand why it doesn't work with BitTorrent. Katherine.J.W. (talk) 14:50, 8 April 2012 (UTC)[reply]

That's a very inefficient way to send a file to one person, though. Ftp would make a lot more sense. Looie496 (talk) 16:02, 8 April 2012 (UTC)[reply]

I know, but the recipient doesn't want to reveal their IP address. Katherine.J.W. (talk) 16:31, 8 April 2012 (UTC)[reply]

Torrenting doesn't hide your IP address. Take a look at the list of peers on your torrent list and there it is. Kind of silly to go to all that trouble for, well, zero security benefit. --Mr.98 (talk) 16:47, 8 April 2012 (UTC)[reply]

Ah, neither of us realised that was visible. Good thing I didn't look! We abandoned the idea though because I was seeding such a minuscule amount to him. We went back to Opera Unite, which gives fairly good speeds but unfortunately doesn't rebuild the file whenever there is an interruption. And Opera crashes a lot. Meaning he's had the first half of the file about half a dozen times! Katherine.J.W. (talk) 10:09, 9 April 2012 (UTC)[reply]

You'd want something like gnunet for private sharing. --145.94.77.43 (talk) 18:21, 10 April 2012 (UTC)[reply]

An alternative way to send a large file to one other person, or a small number of people, is to upload it to a file hosting service, and then notifying them of the file name and service.-gadfium 22:48, 8 April 2012 (UTC)[reply]

USB light

I have a simple USB light which draws power from a USB port. There is no software for it, simply plug it and it lights up. I would like to be able to turn it on and off via the Windows 7 command line (for use in a batch script). I figure the only way to do this would be to selectively disable the USB port it is connected to, but I do not know how to do this. The other USB ports must remain on and unaffected. Is this possible? How would it be done? Operating system is Windows 7. Thank you 82.45.62.107 (talk) 16:35, 8 April 2012 (UTC)[reply]

Someone else out there in internet-land had the same question as you. The answer given then was that it's not really possible as you describe it - without some extra software or hardware, you can really only have all the USB ports on, or all of them off. A couple of other suggestions were made - Drive Disabler, which is some software to allow selective disabling of USB drives, and Devcon, which is a command line tool to do about the same thing. Alternatively, Texas Instruments do something called a USB power switch which might be a hardware solution to what you want. I say might because the documentation is in electronic-engineer-speak, and I'm not fluent. Maybe someone else could have a look and translate. - Cucumber Mike (talk) 17:11, 9 April 2012 (UTC)[reply]

Does windows recognise the USB light as hardware when you plug it in? Mr little irish 10:39, 10 April 2012 (UTC)[reply]