Wikipedia:Reference desk/Archives/Computing/2014 June 17

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June 17

IP Address

When I edit Wikipedia, and when I type "what is my IP address" into Google, I get a response in the form:

2601:x:xxxx:xxx:xxxx:xxxx:xxxx:xxxx

But when I use whatsmyip.org and other IP address finders, I get a response in the form:

73.xx.xx.xxx

Why do I have two IP addresses? — Preceding unsigned comment added by 2601:7:1980:777:5DEE:90A9:1180:F1A9 (talk) 07:41, 17 June 2014 (UTC)

The latter is an IPv4 address, the former an IPv6 address. IPv4 is the original version from the first public internet, which is suffering from address shortage, so the powers-that-be are moving us onto IPv6. CS Miller (talk) 09:53, 17 June 2014 (UTC)

And you'll notice that if you don't sign in with an account name, Wikipedia displays your IP address in the signature line of your posts here...and, interestingly, it uses the IPv6 version. The deal with IPv6 is that it is only slowly being adopted. If you have IPv6 (as you evidently do) then old IPv4 services don't work. For that reason, your Internet Service Provider (ISP) is providing you with an IPv4 address to go alongside the IPv6 address during this transition period. Evidently (and ironically!) the whatsmyip.org site is one of the many that has yet to transition.

There is actually an alarming problem here - the world is running out of IPv4 addresses, and when that happens, we can't hand out any more and some people won't be able to access those old IPv4 web sites and other services. You'd think that web sites and email services and such would be working hard to switch to IPv6 - but they aren't. This is likely to reach a crisis point if those sites don't take notice of the problem soon.

SteveBaker (talk) 15:01, 17 June 2014 (UTC)

delete photo from net

Abhinand1234 (talk) 13:38, 17 June 2014 (UTC)how to delete a unwanted photo of us from website or blog -

If you think they will listen you can ask the person who runs the blog to remove it. There are a few situation where you have legal options, such as if you own the rights to the image and you didn't give them permission to use it, but we can't give legal advice. If you think they will object to removing it then you should be aware of the Streisand effect, which could just make things worse. Katie R (talk) 13:51, 17 June 2014 (UTC)

Of course the image may well stick around in Google's image cache for a considerable time - and you have no control of the number of people who already copied it and might re-post it. Also, people may be accessing cached copies of it for a while yet. Then there is http://archive.org/web/ - which periodically archives the entire "visible" Internet and keeps it forever - so people may be able to find the photo just by looking through old archives of the website/blog.

Bottom line is that being 100% sure that the photo is truly and completely gone is flat out impossible. So don't ever put stuff online that you don't want popping up weeks, months, years or decades from now - don't post anything you don't want your parent/significant-other/boss/kids to see (even if you don't have a significant-other, boss or kid yet!).

SteveBaker (talk) 14:36, 17 June 2014 (UTC)

Also: Streisand effect Zzubnik (talk) 14:20, 18 June 2014 (UTC)

Further Fedora questions

I have now taken the new computer my company gave me into use. I have managed to copy all my old Fedora 17 files to the new Fedora 20 system without problem. But I have some questions:

• As the computer only has two hard disk bays, and both of them are in use (one for Windows 8, the other for Fedora 20), I put my old Fedora 17 disk in a USB enclosure. The computer recognises it when it's the only USB disk plugged in, but not when there's any other USB disk plugged in (I have two more, which I use for backups). This happens even if they are not powered on. Why?
• When the computer recognises the above-mentioned disk, and I turn it on, Fedora tries to be helpful and automatically mounts it and displays its contents in a file browser window. I'd rather want to manage mounting file systems manually. How can I turn this automatic mounting off?
• I have a Creative Zen Vision W device which I use for storing photographs while on the go without access to computers. Fedora 17 used to be able to mount it as an MTP device, but Fedora 20 isn't. All I get is an error message saying the MTP device couldn't be mounted. I did some googling and found numerous bug reports about MTP not working in Fedora 20. Does it work? Can I do something to fix it?
• I was able to install Xine and libdvdcss with yum. I remember I also need xine-lib-extras-nonfree, but no such package exists for Fedora 20. I found something called "xine-lib-extras-freeworld", but when I tried to install it, I was told Xine was already installed. Do I need this? Are Xine and libdvdcss all I need to view commercial DVD content, which I bought fully legally, on Fedora 20 Linux?

JIP | Talk 18:34, 17 June 2014 (UTC)

Companies using pre-computer technology

(1) Which notable companies are not using computers in 2014? (2) Which notable companies are using computers and also pre-computer technology (for example, typewriters, telex, telegrams, land mail, landline telephones, and paper files in filing cabinets) in 2014? (3) For each technology specified in parentheses in the previous question, which notable companies are using that technology? (4) Which notable companies have ceased using computers and have recommenced or expanded the use of pre-computer technology? (For this discussion, let us consider a company to be notable if any language version of Wikipedia has an article about it.)
—Wavelength (talk) 19:27, 17 June 2014 (UTC) and 22:24, 17 June 2014 (UTC)

I doubt there were any notable companies in 1994 that didn't use any computers, let alone 2014. Unless the ONLY thing they are notable for is not using computers, they're so cheap and ubiquitous, even companies in the poorest nations would have access to computers. What does "not using computers" mean anyway? There's no computers at the head office? They don't use online banking? They manually file their tax returns? They manually write out their employee's pay slips? I know people "used" to do this kind of stuff in the past, (I work for a bank and it completely floors me that banks used to keep hand written account records!) but it's SO much more efficient to use computers for the support and operations, even of companies that seemingly have nothing to do with computers, I doubt very much there are any medium to large organizations that use no computers at all. Vespine (talk) 22:45, 17 June 2014 (UTC)

There is an almost obsolete phrase "bankers' hours" which showed a misunderstanding of banking in the 1950's, but refers to the burden of handwritten account records. In the 1950's, banks were open 10 am to 2 pm Mondays through Fridays, and also 4 pm to 6 pm on Fridays. The bank employees actually worked from 9 am to 5 pm on Mondays through Thursdays, and from 9 am to 6:30 pm on Fridays. The remaining time, when the bank was closed to the public, was spent in manual recordkeeping. The introduction of large mainframe computers in the 1960's permitted an expansion of hours, while necessitating the use of night-shift computer personnel, and the use of modern Unix servers permits banks to be open 9 am to 5 pm, or longer at some banks, and on Saturdays. Manual record-keeping really was burdensome, and so of course the banks went to using the most modern computing. Robert McClenon (talk) 19:24, 18 June 2014 (UTC)

Best I can think of is the Kremlin, but I doubt the have eliminated all computers.[1] Even many Amish use some levle of computer technology. --  Gadget850 ^talk 23:23, 17 June 2014 (UTC)

As for #2, I would expect pretty much every company to use both computers and land mail, land line phones, and paper files. In my experience, email, cell phones, and electronic files just aren't as reliable as the old fashioned versions, so keeping the old technology around makes sense.

I agree that land line phones are more reliable than cell phones. There are purposes for which postal mail is necessary, such as when certified mail is required. Robert McClenon (talk) 19:24, 18 June 2014 (UTC)

Related to #1, a company that recently had a security breach and had many of their electronic credit card transactions stolen has gone back to the old credit card sliders to make carbon copies, at least until they can figure out a way to do it electronically in a secure manner. I forget which company it was (maybe Target) ? StuRat (talk) 02:09, 18 June 2014 (UTC)

Advice has been given in regard to being prepared to do business without computers.

• Be Prepared to do Business without Computers - Business Technology, Gadgets, and IT Best Practices from Vantage Point Blog | Louisiana | Vantage Point

—Wavelength (talk) 04:46, 18 June 2014 (UTC)

The company is PF Chang's http://www.pcworld.com/article/2363440/pf-changs-turns-to-manual-card-processing-after-confirming-breach.html --agr (talk) 20:19, 18 June 2014 (UTC)

I'm sorry I only have vague recollections but there was a news item or maybe it was a segment on some History Channel program about 5 years ago now. The show visited some company who did their monthly accounting or payroll on some old (1950s?) piece of equipment. I remember them saying that it takes them extra time but they appreciate the nostalgia of it all. I believe it was a lumber company or some such thing with a rather small number of employees (less than 50?). Sorry I can't be more specific. That said, I don't believe they would meet the "notable" bar that you set. Dismas|^(talk) 08:14, 18 June 2014 (UTC)

According to one report (Ding, click clack -- typewriter is back—Quad-City Times, May 18, 2009), Merls Business Machines in Milan, Illinois, recently sold typewriters to Modern Woodmen of America and to Blackhawk Bank and Trust in Illinois. Another report (Typewriters experience a comeback - UPI.com—United Press International, Dec. 19, 2011) discusses a renewed interest in typewriters, but does not identify any companies buying or using them. There is a movie about the typewriter in the 21st century (http://typewritermovie.com).

—Wavelength (talk) 16:14, 18 June 2014 (UTC)

Russian security agency now using typewriters to avoid electronic surveillance.[2] 192.249.63.59 (talk) 02:52, 19 June 2014 (UTC)

Hexadecimal

I'm interested in learning more about the hexadecimal numeral system, how to use it, and some basic conversion examples to get me started. I already know that it is base 16, and that in addition to the numerals 1–9, there is also A–F — each representing its own distinct value (i.e. "A" in hexadecimal is equal to "10" in decimal, "B" = "11", "C" = "12"). And after the first "F", it resets to 11, 12, 13, and so on, until it returns to the alphabetized six values representing 10-15 (as in the basic decimal system. Then it follows up with an example. It reads as follows:

“ For example, the hexadecimal number 2AF3 is equal, in decimal, to (216 × 163) + (A16 × 162) + (F16 × 161) + (316 × 160),

(2 × 4096) + (10 × 256) + (15 × 16) + (3 × 1), or 10995.

”

I can't possibly be the only person who finds this part confusing. As someone who knows virtually nothing about hexadecimal, that example does not help to educate me about converting from the standard base 10 numeral system. It just presents an equation using conversions the reader is presumed to know. I think the lead section should be partially revised, so as to give a better introduction to the topic for the unenlightened masses (i.e. myself). Kurtis ^(talk) 23:35, 17 June 2014 (UTC)

Um, you've copied the section from the article without the formatting, which is even more confusing. It actually says:

For example, the hexadecimal number 2AF3 is equal, in decimal, to (2₁₆ × 16³) + (A₁₆ × 16²) + (F₁₆ × 16¹) + (3₁₆ × 16⁰),
(2 × 4096) + (10 × 256) + (15 × 16) + (3 × 1), or 10995.

I'd agree that it could probably be better explained though. AndyTheGrump (talk) 23:49, 17 June 2014 (UTC)

Looking into this further, the article used to read

For example, the hexadecimal number 2AF3 is equal, in decimal, to (2 × 16³) + (10 × 16²) + (15 × 16¹) + (3 × 16⁰), or 10995.

I'm not sure that this wasn't less confusing... AndyTheGrump (talk) 00:04, 18 June 2014 (UTC)

• Oh... sorry about the formatting error. Forgot that it used subscripted numbers as well. But thanks for correcting me. Hopefully we can find some better way to represent hexadecimal in action (i.e. proper conversion from base 10). Kurtis ^(talk) 01:08, 18 June 2014 (UTC)

It might help to start at the small digits, rather than the large digits, as the math is simpler for them. Also, using the subscript "HEX" instead of "16" might make it clearer. StuRat (talk) 02:13, 18 June 2014 (UTC)

The number $10995_{10}$ is equal to $1*10^{4}+0*10^{3}+9*10^{2}+9*10^{1}+5*10^{0}=10000+000000+00900+00090+00005$ is one way of looking at the decimal system, especially if you remember how to do long arithmetic. CS Miller (talk) 10:44, 18 June 2014 (UTC)

For what it's worth, I tried to edit the introduction of the hexadecimal article for clarity. If you have input, there is a discussion at the article talk page. Nimur (talk) 22:42, 20 June 2014 (UTC)