Template talk:Quantities of bits

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"Note that the IEC names are defined only up to exbi-, corresponding to the SI prefix exa-. The two SI prefixes zetta- (1021) and yotta- (1024) have no corresponding IEC binary prefixes, though the obvious continuation would be zebi- (Zi = 270 = 10007 × 1.180 591 620 717 411 303 424) and yobi- (Yi = 280 = 10008 × 1.208 925 819 614 629 174 706 176)."

Contents

[edit] See also

[edit] Use of parenthesis

Why are parentheses being used to distinguish between the decimal and binary sense of the units? This distinction is the most confusing part of the table. It deserves its own column to keep the two clearly separated. Lets join the Symbol and Name columns with parentheses instead. Those values are much less likely to be confused. Also, this helps to demonstrate that "Kibit" is a non-pronounceable symbol for kibibit just as "kb" is a non-pronounceable symbol for kilobit. This is an important distinction which was not apparent in the previous table. 12.135.134.146 22:52, 6 September 2006 (UTC)

I've reverted this, as it made the table look even messier than it did before. --StuartBrady (Talk) 22:14, 19 September 2006 (UTC)

[edit] 1kb can = 1024 bits

Since a byte equals 8 bits, and 1 KB can equal 1024 bytes, 1 Kb therefore can equal 1024 bits. Microsoft, for example, in their operating systems counts 1024 bits as a kb, as does most networking software for windows, such as Net.Medic, and cfosspeed, both of which I use. --Rebroad 21:31, 10 March 2006 (UTC)

According to Microsoft (pretty much an expert witness in this area), they define a kilobit as 1024 bits. See here. Therefore, I'm reverting the article, until the previous reverter quotes a definitive and reputable source that claims a kilobit is NOT 1024 bits. Thanks. --Rebroad 21:36, 10 March 2006 (UTC)

  1. That's an ad, not a reliable source.
  2. It's not even internally consistent. It says kbps = 1,024 bit/s, but then says that a 56K modem is 56,000 bit/s.

PC magazine (another knowledgeable IT source) see here also says it is 1024 bits. --Rebroad 21:38, 10 March 2006 (UTC)

  • Their entry is actually from [1]
  • It also says "In order to avoid confusion between the decimal and binary numbers, the IEC standardized the terms kibi, mebi, gibi, tebi, pebi and exbi to represent binary numbers (compared to kilo, mega, giga, tera, peta and exa)."
  • Their definition of megabit? "One million bits"
  • This usage is not widely known or adhered to and most modem ratings use Kbps. For example, 56 Kbps means 56,000 bps and not 56 times 1,024 bps.

About.com also says it can equal 1024 bits (in addition to saying it often means 1000 bits). See here. --Rebroad 21:39, 10 March 2006 (UTC)

  • Uh... it says: "Many people less familiar with computer networking believe one kilobit equals 1024 bits." How is that support for your position?
    • Even if 1 kilobit does equal 1000 bits, the fact that so many people use it when they mean 1024 is a fact, and should therefore be included in the article, especially when the majority of people say 1 kilobit when they are referring to 1024 bits. --Rebroad 17:13, 11 March 2006 (UTC)
      • Such as who? All I see are some dubious web references, probably just extending the definition from "kilobyte". I'm sure a few people use 1 kilobit = 1,024 bits, which is why it's included in the kilobit article, but it is definitely not the standard, and not the majority, and doesn't belong in this template. The burden of proof is on you to produce a majority of people. I don't think you can. If you can produce any evidence of a significant number of scientists, engineers, product manufacturers, telecommunications experts, or other relevant people using kilobit = 1,024 on a daily basis (not just defining it in a web glossary), I will change my mind. — Omegatron 18:17, 11 March 2006 (UTC)
        • You state the burden of proof should be on me, without explain why. I have worked in IT for over 10 years, and with computers since 1979. All of that time, 1 kilobyte has equalled 1 byte. As 1 byte equals 8 bits, kilobits and kilobits per second can be derived in the same way. --Rebroad 14:20, 14 March 2006 (UTC)
    • The article actually says "This is generally untrue in networking but may be true in other contexts.". Did you not read this bit? I am not disputing that 1 kilobit sometimes equals 1000 bits, but it also sometimes equals 1024 bits "in other contexts", so why do you chose to remove this bit of information? --Rebroad 17:17, 11 March 2006 (UTC)
      • Many people less familiar with computer networking believe one kilobit equals 1024 bits. This is generally untrue in networking but may be true in other contexts. Specifications for today's adapters, routers and other networking equipment always use 1000-bit kilobits as the basis of their quoted data rates. The confusion arises as computer memory and disk drive manufacturers often use 1024-byte kilobytes as the basis of their quoted capacities.
      • This is how I read it, paraphrased: "Many people unfamiliar with computer networking incorrectly believe that kilobit = 1024 bits. This is definitely untrue in networking, though it might be true in other fields that I don't know about. Specifications for networking stuff always uses the 1,000 definition, and the confusion is probably caused by people mixing up kilobits and kilobytes." Do you read it differently? Kilobit usually means 1,000. This isn't the same as kilobyte, which we all agree means 1,024 most of the time and has a popular usage in software. There is no popular usage of kilobit that means 1,024. Is there? Can you prove it? — Omegatron 18:17, 11 March 2006 (UTC)

Also Total Telecom (an IT communications expert) says here that a kilobit is 1024 bits. --Rebroad 21:47, 10 March 2006 (UTC)

  • Dubious source. It also says a megabit is 1,048 kilobits (not 1,024), a gigabit is 1,000,000,000 bits, and a terabit is "one trillion bits".


Just because lots of people use something incorrectly doesn't make it correct. Here are some equally dubious web glossaries:
  • In data communications, a kilobit is a thousand (103) bits. It's commonly used for measuring the amount of data that is transferred in a second between two telecommunication points. Kilobits per second is usually shortened to Kbps.*
    Some sources define a kilobit to mean 1,024 (that is, 210) bits. Although the bit is a unit of the binary number system, bits in data communications are discrete signal pulses and have historically been counted using the decimal number system. For example, 28.8 kilobits per second (Kbps) is 28,800 bits per second. Because of computer architecture and memory address boundaries, bytes are always some multiple or exponent of two. See kilobyte, etc. — whatis.com
  • Old standard: kilobyte = 1024 bytes, kilobit = 1000 bits, New standard: kilobyte = 1000 bytes, kilobit = 1000 bits — [2]
Can you quote a reliable and definitive source that defines a kilobit as 1,024 bits? Can you name a product that uses that definition? There may be a handful, but I can't find any, and a handful of people using something doesn't make it correct or "common usage".
Kilobytes are ambiguous, but kilobits are not. — Omegatron 01:50, 11 March 2006 (UTC)
Omegatron, thank you for quoting a relevant example, the 28.8kps example. To be honest, I had not realised this. Obviously the people who decided to call 288000 bps as 28.8kbps weren't thinking straight when they did this, as a kilobit has equalled 1024 bits long before modems became this fast! What a mess we're in now. I totally agree that I would prefer everything to be unambiguous, but I can't quite see what anyone in the industry is doing about it. Some sort of deadline needs to be created where once past that point corporations will be in breach of trade descriptions etc. Why doesn't SI create an unambigious term for decimal prefix with regards to bits and bytes? IMHO one is needed, and kilo, mega, etc need to be phased out in the interim period.... IMHO, since kilobyte and kilobit existed in binary prefix long before decimal prefix, then the binary prefix definition is the more worthy. Kilo and Mega mean 1000 and 1000000 for most things, watts, volts, grammes, etc, but when it comes to bits and bytes it should be base 2 - I mean, who's to say base 10 should be dominant, just because humans have 10 fingers? --Rebroad 17:35, 11 March 2006 (UTC)
I'm sorry for being a bit impatient. I was confusing you with someone else I am currently having a similar conversation with who insists that the standards institutes are just "a small group of pedants". I've included the official definitions below, which I probably should have included in the first place. No one is producing an unambiguous prefix for decimal quantities, since the SI prefixes are supposed to be unambiguous. As far as the SI is concerned, they are being misused. Should we have two prefixes to mean the same thing?
IMHO, since kilobyte and kilobit existed in binary prefix long before decimal prefix
But they didn't. The original usage was consistent with the SI prefixes, it was just an approximation. 1024 bytes is 1.024 kB, and it's perfectly fine to refer to it as "1 kilobit", when everyone knows that you're abbreviating. It's the fact that it was treated as an official definition and extended to higher powers that causes all the confusion. — Omegatron 18:24, 11 March 2006 (UTC)

If nothing else, I think putting both interpretations of the SI prefix names in this template fails to meet NPOV: The conventional usage of these terms varies from one field of data processing to another. In order to keep this template more generally applicable, it should simply and objectively state the official, standard definitions, which in some situations are the only ones that are in use. Then, on a case-by-case basis, entries that include this template can decide if an additional note (or template) is appropriate to describe the conventional usage in the specific field being discussed. Mditto 23:33, 11 March 2006 (UTC)

I believe that's what we agreed on a while ago. Hence the explicit "SI prefixes"/"IEC prefixes". Remember that this is just a navigational template, not a portal. Anyone viewing the template is also inherently viewing one of the unit pages, so they are still seeing the special cases for the unit they are interested in. — Omegatron 00:57, 12 March 2006 (UTC)

[edit] Some non-dubious definitions

  • NIST
    • "Because the SI prefixes strictly represent powers of 10, they should not be used to represent powers of 2. Thus, one kilobit, or 1 kbit, is 1000 bit and not 210 bit = 1024 bit." nist.gov
  • SI/BIPM
    • "These SI prefixes refer strictly to powers of 10. They should not be used to indicate powers of 2 (for example, one kilobit represents 1000 bits and not 1024 bits)." [3]
  • IEEE
    • Information for authors - "Information for IEEE Transactions, Journals, and Letters Authors"
      • TABLE OF UNITS AND QUANTITY SYMBOLS
      • "kilo-: SI prefix for 103. The prefix kilo shall not be used to mean 210 (that is, 1024)."
    • IEEE Standard Letter Symbols for Units of Measurement, IEEE Std 260.1-2004 (p13)
  • ANSI
  • SAE
    • "Thus 1 kbit = 103 bit = 1000 bit and not 210 = 1024 bit, where 1 kbit is one kilobit." [4]
  • RFC
  • IEC
    • IEC 60027-2, Letter symbols to be used in electrical technology - Part 2: Telecommunications and electronics, p121
      • one kibibit = 1 Kibit = 210 bit = 1 024 bit
      • one kilobit = 1 kbit = 103 bit = 1 000 bit —Preceding unsigned comment added by Thunderbird2 (talk • contribs) 13:19, 21 October 2007 (UTC)

[edit] unit symbol for bit

I find the template confusing. On the left it uses the symbol b for bit (as in Mb for megabit) and on the right it uses bit for the same purpose (Mibit for mebibit). Why not pick one of them and stick with it? See also WP:MOSNUM talk page Thunderbird2 13:27, 21 October 2007 (UTC)

I have edited the template to standardise on bit as the symbol for the bit, in line with the consensus reached at MOSNUM. Thunderbird2 15:15, 4 November 2007 (UTC)