Binary Prefix
Binary prefix - Wikipedia, the free encyclopedia
In computing, binary prefixes are names or associated symbols that ... prefixes in binary sense. 2.2 IEC standard prefixes ... of binary prefixes ...
en.wikipedia.org
Timeline of binary prefixes - Wikipedia, the free encyclopedia
Timeline of binary prefixes. From Wikipedia, the free encyclopedia. Jump to: ... IEC introduces unambigous prefixes for binary multiples (KiB, MiB, GiB etc. ...
en.wikipedia.org
Definitions of the SI units: The binary prefixes
Prefixes for binary multiples ... of the SI prefix and adding the letters " ... ( For consistency with the other prefixes for binary multiples, the symbol Ki is ...
physics.nist.gov
Binary prefix - Open Encyclopedia
In computing, binary prefixes are often used to quantify large numbers where ... IEC prefixes and symbols for binary multiples. http://physics.nist.gov/cuu ...
open-encyclopedia.com
Binary prefix - Encyclopedia of Earth
In computing, binary prefixes frequently are used to quantify large numbers ... ( For consistency with the other prefixes for binary multiples, the symbol Ki is ...
www.eoearth.org
Units: Metric Prefixes
However, the last letter of the prefix is not omitted if pronunciation is not a ... Binary prefixes ... So far, very few people are using the IEC binary prefixes. ...
www.unc.edu
Coding Horror: Gigabyte: Decimal vs. Binary
... drive using the computer's binary powers of two definition of the "Giga" prefix: ... You're so right - those binary prefixes sound soo ridiculous. ...
www.codinghorror.com
Prefix Compression of Sparse Binary Strings
Compressing sparse binary strings by means of common prefix. ... ACM / Crossroads / Xrds6-3 / Prefix Compression of Sparse Binary Strings ...
www.acm.org
Physics reference: Binary prefixes
A comphrensive table of all binary multiples. ... with the other binary prefixes, the symbol for the prefix kibi is Ki, whereas ...
www.alcyone.com
units(7): decimal/binary prefixes - Linux man page
... kibi, mega, mebi, giga, gibi - decimal and binary prefixes. Description ... The binary prefixes resemble the decimal ones, but have an additional 'i' (and " ...
linux.die.net
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In computing, Binary numeral system prefixes can be used to quantify large numbers where powers of two are more useful than powers of ten (such as computer memory sizes). Each successive prefix is multiplied by 1024 (210) rather than the 1000 (103) used by the SI prefix system. Binary prefixes are often written and pronounced identically to the SI prefixes, despite the resulting ambiguity.
History Early computers used one of two addressing methods to access the system memory; binary (base-2) or decimal (base-10). For instance, the IBM 701 (1952) used binary and could address 2,048 36-bit words, while the IBM 702 (1953) used decimal and could address 10,000 7-bit words.
One of the most successful early computers was the IBM 1401. It was introduced in 1959 and by 1961 one out of every four electronic stored-program computers was an IBM 1401. It used decimal addressing and could have 1400, 2000, 4000, 8000, 12000 or 16000 characters of 8-bit Magnetic core memory storage. These sizes were often abbreviated, borrowing the k from the SI prefix; a reference to a "4k IBM 1401" meant 4,000 characters of storage (memory).
By the mid 1960s, binary addressing had become the standard architecture in computer design. The computer system documentation would specify the memory size with an exact number such as 32,768, 65,536 or 131,072 words of storage (all powers of 2). There were several methods used to abbreviate these quantities. The use of K in the binary sense as in a "32K store" can be found as early as 1960. "The 8K core stores were getting fairly common in this country in 1954. The 32K store started mass production in 1956; it is the standard now for large machines and at least 200 machines of the size (or its equivalent in the character addressable machines) are in existence today (and at least 100 were in existence in mid-1959)." Note: The IBM 1401 was a character addressable computer. Gene Amdahl seminal 1964 article on IBM System/360 used 1K to mean 1024. Figure 1 gives storage (memory) capacity ranges of the various models in "Capacity 8 bit bytes, 1 K = 1024" This style was used by other computer vendors, the CDC 7600 System Description (1968) made extensive use of K as 1024. Another style was to truncate the last 3 digits and append K. The exact values 32,768, 65,536 and 131,072 would then become 32K, 65K and 131K. (If 32,768 were instead rounded off, it would be 33K; if K = 1024 were used, 65,536 would become "64K".) This style was used from about 1965 to 1975.
These two styles (K = 1024 and truncation) were used loosely around the same time, sometimes by the same company. (In discussions of binary-addressed memories, the exact size was evident from context.) The HP 2100 real-time computer (1974) denoted 196,608 as 196K and 1,048,576 as 1 M, while the HP 3000 business computer (1973) could have 64K, 96K, or 128K bytes of memory.
The terms Kbit, Kbyte, Mbit and Mbyte started to be used as binary units in the early 1970s. Most memory capacities were expressed in K, even when M could have been used: The IBM System/370 Model 158 brochure (1972) had the following: "Real storage capacity is available in 512K increments ranging from 512K to 2,048K bytes." Megabyte was used to describe the 22-bit addressing of DEC PDP-11/70 (1975)The names for the new standard are derived from the first two letters of the original SI prefixes followed by bi, short for "binary". The new standard also clarifies that, from the point of view of the IEC, the SI prefixes will henceforth only have their base-10 meaning and never have a base-2 meaning.
The second edition of the standardIEC 60027-2 (2000-11) Ed. 2.0 defined them only up to exbi-, but in 2005, the third edition added prefixes zebi- and yobi-, thus matching all standard SI prefixes with their binary counterparts.
On March 19, 2005 the IEEE standard IEEE 1541-2002 (Prefixes for Binary Multiples) was elevated to a full-use standard by the IEEE Standards Association after a two-year trial period.
Consumer confusion In the early days of computers there was little or no consumer confusion because of the sophisticated nature of the consumers and the practice of the computer manufacturers to specify (as opposed to advertisement) their products with decimal digits of sufficient places, e.g., the 1968 IBM stated System 360 "Model 91s can accommodate up to 6,291,496 bytes of main storage." System/360 Model 91
Hard disk drive manufacturers used MB, i.e. 106 bytes, to characterize their products as early as 1974.The Product Line Card unambiguously uses MB to characterize HDD capacity in millions of bytes By 1977, in its first edition, Disk/Trend, a leading hard disk drive industry marketing consultancy segmented the industry according to MB's (decimal sense) of capacity.1977 Disk/Trend Report - Rigid Disk Drives, published June 1977
The presentation of hard disk drive capacity by an operating system using MB in a binary sense appears no earlier than Macintosh Finder after 1984. Prior to that, on the systems that had a hard disk drive, capacity was presented in decimal digits with no prefix of any sort (e.g., MS/PC DOS CHKDSK command).
See, for example, the following two images; consumers may be confused by the difference between the 160 GB on the disk drive package and the 149.05 GB reported by the operating system.
Image:Seagate 160 GB hard drive box.jpg]es as "160 GB"Image:Windows XP Disk management for 160 GB disk.png|Windows XP lists the capacity of a 160×109 byte disk drive as "149.05 GB" (binary).Image:DOS310_Chkdsk.JPG|Screen shot of PC-DOS 3.10 CHKDSK showing disk drive size in decimal digits without prefixes of any sort (or even commas).
Binary prefixes using SI symbols {|align="center" border="1" cellspacing="0" cellpadding="3" class="wikitable"|-! Name! Symbol! Value! Base 16! Base 10|-|align="center"| kilo|align="center"| M| 220 = 1,048,576| = 165| > 106|-|align="center"| [giga|align="center"| T| 240 = 1,099,511,627,776| = 1610| > 1012|-|align="center"| [Peta (prefix)|align="center"| P| 250 = 1,125,899,906,842,624| = 1612.5| > 1015|-bgcolor="#ffff99"|align="center"| exa|align="center"| Z| 270 = 1,180,591,620,717,411,303,424| = 1617.5| > 1021|-bgcolor="#ffff99"|align="center"| [yotta, and only the lower-case "k" represents 1,000).
These prefixes are in common use in contexts such as file and memory sizes. The names and values of the [SI prefixes were defined in the 1960 SI standard, with powers-of-1000 values. Standard dictionaries do recognize the binary meanings for these prefixes. Oxford online dictionary define, for example, megabyte as: "Computing a unit of information equal to one million or (strictly) 1,048,576 bytes."
BIPM (the International Bureau of Weights and Measures which maintains SI) expressly prohibits the binary prefix usage, and recommends the use of #IEC standard prefixes as an alternative since computing units are not included in SI.
Some have suggested that "k" be used for 1,000, and "K" for 1,024, but this cannot be extended to the higher order prefixes and has never been widely recognised.
Although the SI prefixes denoting fractions of a bit or byte might theoretically find application in areas such as cryptography, data compression, and data transfer rates, they are not used in practice.
Informally, the prefixes are often used on their own. Thus one might hear about a "256K DRAM" (256 binary kilobytes), "a 160 MB HDD" (160 decimal megabytes) or "a 2M Internet connection" (2 decimal megabits per second). What units are being used, and whether the multipliers are decimal or binary, depends on context and cannot be determined by the units alone.
Image:Windows XP Drive Properties for 160 GB disk.png|Windows XP lists the capacity of a 160×109 byte disk drive as "152625 MB" (binary).Image:Windows XP C partition properties.png|Windows XP used to list the size of a 73×109 byte disk drive partition as "68.1 GB" (binary).
IEC standard prefixes {|align="center" border="1" cellspacing="0" cellpadding="3" class="wikitable"|-! Name! Symbol! Base 2!colspan="2"| Base 16!colspan="2"| Base 10|-| kibi| Ki| 210| 162.5|align="right"| 400(16)| = 1,024| > 103|-bgcolor="#ffff99"| mebi| Mi| 220| 165|align="right"| 10 0000(16)| = 1,048,576| > 106|-| gibi| Gi| 230| 167.5|align="right"| 4 000 0000(16)| = 1,073,741,824| > 109|-bgcolor="#ffff99"| tebi| Ti| 240| 1610|align="right"| 100 0000 0000(16)| = 1,099,511,627,776| > 1012|-| pebi| Pi| 250| 1612.5|align="right"| 4 0000 0000 0000(16)| = 1,125,899,906,842,624| > 1015|-bgcolor="#ffff99"| exbi| Ei| 260| 1615|align="right"| 1000 0000 0000 0000(16)| = 1,152,921,504,606,846,976| > 1018|-| zebi| Zi| 270| 1617.5|align="right"| 40 0000 0000 0000 0000(16)| = 1,180,591,620,717,411,303,424| > 1021|-bgcolor="#ffff99"| yobi| Yi| 280| 1620|align="right"| 1 0000 0000 0000 0000 0000(16)| = 1,208,925,819,614,629,174,706,176| > 1024|}
Example: 300 GB ≅ 279.5 GiB.
Approximate ratios between binary & decimal prefixes As the order of magnitude increases, the percentage difference between the binary and decimal values of a prefix increases, from 2.4% (with the kilo prefix) to over 20% (with the yotta prefix). This makes differentiating between the two increasingly important as larger and larger data storage and transmission technologies are developed.
{|align="center" border="1" cellspacing="0" cellpadding="3" class="wikitable"|-bgcolor="#ccccff"! Name! Bin ÷ Dec! Dec ÷ Bin! Example! Percentage difference|-| kilobyte : kibibyte : [mebibyte : [gibibyte : [tebibyte : [pebibyte : [exbibyte : [zebibyte : [yobibyte| 1.209| 0.827| 100 YB ≅ 82.7 YiB| +20.9% or −17.3%|}
Adoption As of 2007, the International Electrotechnical Commission binary naming convention is not widespread. Most publications, computer manufacturers and software companies are still using the traditional binary units defined in IEEE 100, The Authoritative Dictionary of IEEE Standards Terms, Seventh Edition, 2000.
It is strongly supported by many standardization bodies and technical organizations, such as IEEE, CIPM, NIST, and SAE. Prefixes for Binary Multiples — The NIST Reference on Constants, Units, and Uncertainty Rules for SAE Use of SI (Metric) Units — Section C.1.12 — SI prefixesThe new binary prefixes have also been adopted by the European Committee for Electrotechnical Standardization (CENELEC) as the harmonization document HD 60027-2:2003-03. HD 60027-2:2003 Information about the harmonization document (obtainable on order)This document will be adopted as a CEN. prEN 60027-2:2006 Information about the EN standardization process
The prefixes are beginning to be used in technical articles and software where it is important to avoid ambiguity. The PC Guide, for example. Examples of software that use IEC standard prefixes (along with standard SI prefixes) include the Linux kernel,{{cite web]|work=Manual page (Unix)|quote=When the Linux kernel boots and says hda: 120064896 sectors (61473 MB) w/2048KiB Cache the MB are megabytes and the KiB are kibibytes.--> GNU Core Utilities,{{cite web]|work=GNU Core Utilities manual]|quote=Integers may be followed by suffixesthat are upward compatible with the SI prefixes for decimal multiples and with the IEC 60027-2 prefixes for binary multiples.--> Launchpad (website), GParted,{{cite web]|work=SourceForge,{{cite web|url=http://www.annodex.net/cgi-bin/man/man2html?8+ifconfig|title=IFCONFIG|accessdate=2007-05-20|date=[2005-06-30|quote=Since net-tools 1.60-4 ifconfig is printing byte counters and human readable counters with IEC 60027-2 units. So 1 KiB are 2^10 byte.--> [Deluge (BitTorrent client), {{cite web]. Other programs like fdisk and apt-get use SI prefixes with their decimal meaning.
It can be argued that the main purpose of the binary prefixes is to clarify that, according to national and international standards, the traditional SI prefixes always refer to powers of ten, even in the context of information technology. Therefore, rather than measuring the success of the binary prefixes based on how commonly they appear in technical and marketing literature, it may be more appropriate to judge them by their success in restoring the original power-of-ten meaning of the standard SI prefixes in information technology. Binary prefixes are only convenient for a small number of information-technology quantities, most notably the size of address spaces (e.g., of RAM chips). They provide no practical advantage for quantities where powers-of-two times a small integer are not preferred numbers, such as file sizes, download speeds, line rates, symbol rates, clock frequencies, tape or disk capacities. There, decimal prefixes are far more convenient for mental arithmetic.
Image:Gnome Partition Editor showing 160 GB disk.png]'s partition editor uses IEC prefixes to display partition sizes. The total capacity of the 160×109 byte disk is displayed as "149.05 gibibyte"Image:GNOME System Monitor memory size and network rate.png|GNOME's system monitor uses IEC prefixes to show memory size and networking data rate.Image:Bittornado screenshot showing use of IEC and SI prefixes.png|BitTornado uses standard SI prefixes for data rates and IEC prefixes for file sizesImage:Deluge_using_Si_prefix_for_wiki_CD.png] uses IEC prefixes for data rates as well as file sizesImage:Fdisk showing 160 GB disk.png|Linux's fdisk uses standard SI prefixes to display a 160×109 byte disk as "160.0 GB"
Usage notes In this section, the phrase "decimal unit" will be used to denote "SI designation understood in its standard, decimal, power-of-1000 sense" and "binary unit" will mean "SI designation understood in its binary, power-of-1024 sense." B will be used as the symbol for byte as per computer-industry standard (IEEE 1541 and IEC 60027; B is also the symbol for decibel, a common non-SI unit used to quantify power ratios on a logarithmic scale).
Certain units are always understood as decimal even in computing contexts. For example, hertz (Hz), which is used to measure clock rates of electronic components, and bit/s, used to measure bit rate. So a 1 GHz processor performs 1,000,000,000 clock ticks per second, a 128 kbit/s MP3 stream consumes 128,000 bits (16 kB, 15.625 KiB) per second, and a 1 Mbit/s Internet connection can transfer 1,000,000 bits (125 kB, approx 122 KiB) per second, assuming an 8-bit byte, and no overhead. Binary vs. Decimal Measurements
Pronunciation It is suggested that in English, the first syllable of the name of the binary-multiple prefix should be pronounced in the same way as the first syllable of the name of the corresponding SI prefix, and that the second syllable should be pronounced as "bee."
Computer memory
Measurements of most types of electronic computer memory such as Random Access Memory and Read-only memory and Flash memory (large scale disk-like flash is sometimes an exception) are given in binary units, as they are made in power-of-two sizes. This is the most natural configuration for memory, as all combinations of their address lines map to a valid address, allowing easy aggregation into a larger contiguous block of memory.
JEDEC Solid State Technology Association, the semiconductor engineering standardization body of the Electronic Industries Alliance (EIA) in Standard 100B.01{{Citation | last = JEDEC Solid State Technology Association | title = Terms, Definitions, and Letter Symbols for Microcomputers, Microprocessors, and Memory Integrated Circuits | journal = JESD 100B.01 | date = December 2002--> defines in the binary sense K, M and G as prefixes to units of semiconductor memory, noting that these definitions are “only included to reflect common usage” and noting that ‘IEEE/ASTM SI 10-1997 state “This practice frequently leads to confusion and is deprecated.” ’. All standards published by JEDEC are still using the common usage, including end-user packaging recommendations for memory chips.
Many computer programming tasks naturally reference memory in terms of powers of two. For example, a 16-bit Pointer (computing) can reference at most 65,536 items (bytes, words, or other objects), or an operating system might map memory in terms of 4,096-byte pages, in which case exactly 8,192 pages could be allocated within 33,554,432 bytes of hardware memory. It is convenient to informally express these numbers, respectively, as 64K items, or as 8K pages of 4 Kbytes (KiB) each within 32 MBytes (MiB) of memory. A programmer can easily mentally calculate that "8K × 4K is 32 meg" and get it exactly right, within this powers-of-two context. This convenience is likely one source of originally adapting "kilo" and "mega" from SI as shorthand for 1,024 and 1,048,576, as specialized jargon within a segment of the industry.
Almost all computer user tasks (and many high-level programming tasks) have no natural affinity or need for explicit powers of two. The consumer confusion between powers of 1000 and powers of 1024 may derive largely from some operating systems and applications that were originally written by and for programmers, and which thus reported quantities such as file sizes in familiar (to programmers) powers of 1024 while using SI (powers of 1000) abbreviations. Without such reporting, most users might not have been substantially exposed to powers of 1024, as the net memory available to users after various overheads is rarely a power of two. This legacy behavior of operating systems reporting sizes in powers of 1024 has continued to this day (in 2007) even in many GUI oriented operating systems intended mainly for non-programmers.
Hard disk drives hard disk manufacturers state capacity in decimal units. This usage has a long tradition, even predating the SI prefixes adopted in 1960, as follows:
- The first disk drive the IBM Ramac (1950s) had 5,000,000 6 bit characters organized in 100 character sectors (i.e., blocks). This predates the SI system.
- In the 1960s virtually all disk drives used IBM's variable block length format (called, Count Key Data or "CKDhttp://www.answers.com/topic/ckd"). Any block size could be specified up to the maximum track length. Blocks ("records" in IBM's terminology) of 88, 96, 880 and 960 were often used because they related to the fixed block size of punch cards. The drive capacity was usually stated in full track record blocking, for example, the 100 Megabyte 3336 disk pack only achieved that capacity with a full track block size of 13,030 bytes.
- CKD continued into the 1990s and perhaps into this day. In the 1970s and 1980s most drives were specified with unformatted tracks (the unformatted capacity) with the particular block size and formatted capacity a function of the controller design. For example, the ST412 of IBM PC/XT fame had an unformatted capacity of 12.75 MB (not MiB) and with the Xebec controller and 512 byte blocks it formatted to and was advertised as a 10.0 MB (not MiB) HDD. Other controllers supported other block sizes resulting in other formatted capacities.
- The advent of intelligent interfaces (SCSI and AT Attachment) in the early 1990s took the block size decision into the drive and virtually all chose 512 bytes, for no reason other than that was what IBM had chosen when they picked the Xebec controller for the PC/XT. Capacity continued to be specified by the HDD manufacturers with SI prefix definitions.
Flash drives USB Flash Drive and Flash-based memory cards like CompactFlash and Secure Digital are typically classified in "powers of two" multiples of decimal megabytes; for example, a "256 MB" card would hold 256 million bytes.{{cite web | url = http://www.sandisk.com/Assets/Categories/Products/sd_capacitydisclaimer.pdf | title = "Secure Digital Capacity Disclaimer" | format = [PDF | work = sandisk.com | publisher = [SanDisk | accessdate = 2007-09-09 -->Although the devices usually have at least the expected byte capacity, each manufacturer allocates different portions of the device's ultimate capacity for such things as wear levelling.
Floppy drives Floppy disk drive and media manufacturers use decimal units for unformatted recording capacity while most computer operating systems use binary units to measure the formatted capacity. The original IBM Personal Computer (1981) used a :Image:IBM_Floppy_Drive_With_DOS.jpg 5¼ inch floppy disk drive. The single sided drive was rated at 250 kilobytes (unformatted) and the double sided version was rated at 500 kilobytes.
A 5¼ inch diskette recorded at double density Modified Frequency Modulation will hold 6,250 bytes per track and has 40 tracks per side, yielding 250,000 bytes per side. To make it practical to record smaller blocks of data, the tracks are formatted into sectors with gaps between them. The gaps allow individual sectors to be recorded without overwriting adjacent sectors. Each sector also has additional header bytes to identify the sector.
With IBM PC-DOS 1.0 and 1.1, each track has 8 sectors of 512 bytes and this provides 163,840 bytes per side (8 × 512 × 40). The IBM user documentation referred to this as "160KB" for single sided diskette and "320KB" for double sided diskette. Some software applications "used with DOS 1.10, will operate with either two 160KB drives or two 320KB drives. Both drives MUST be of the same type…" Starting with PC-DOS 2.0 (1983), each track had 9 sectors of 512 bytes. The formatted capacity was increased to 184,320 bytes per side or 368,640 bytes per diskette. The IBM documentation referred to these as "180KB" and "360KB" diskettes. The same drives and media can have different capacities depending on format. "Beginning with DOS Version 2.00, DOS formats diskettes at 9 sectors per track, which increases capacity from 163,840 to 184,320 characters of information for single-sided diskettes and from 327,680 to 368,640 characters for dual-sided diskettes. The smaller capacity diskettes created by DOS Version 1.00 or DOS Version 1.10 (8 sectors per track) are also usable with DOS Version 2.00."
On all diskettes the capacity available to the user will be smaller that the total number of sectors because some are reserved by the operating system for boot records or directory tables.
The IBM Personal Computer/AT (1984) had a new 5¼ inch disk drive that had 80 tracks per side, rotated at 360 rpm (versus 300 rpm) and had a new diskette media. The formatted capacity was 1,228,800 bytes or 1200 KiB. (80 tracks × 15 sectors × 512 bytes × 2 sides)
The IBM PC Convertible (1986) used the 3½ inch diskettes. These were similar in recording technology to the original 5¼ inch drives except they had 80 tracks per side. The formatted capacity was 737,280 bytes or 720 KiB. Apple used the same disk with a different recording technology, Group code recording, that gave a formatted capacity of 819,200 bytes or 800 KiB. Apple referred to this as an "800K" disk.{{cite web | last =Apple Inc. | title = Double-Density Versus High-Density Disks | publisher = Apple Inc. | date =August 22, 1991 | url = http://docs.info.apple.com/article.html?artnum=3802| work = Article ID: 3802| accessdate = 2007-07-07--> "This article gives the specifications for the 800K floppy disks and the1.4MB floppy disks." 800K Disk has 1600 sectors and 1.4MB Disk has 2880 sectors. A sector is 512 bytes.
The last widely adopted diskette was the 3½ inch high density. This has twice the capacity as the 720 KB diskettes, 1,474,560 bytes or 1440 KB. The drive was marketed as 1.44 MB when a more accurate value would have been 1.4 MB (1.40625 MB). Some users have noticed the missing 0.04 MB and both Apple and Microsoft have support bulletins referring to them as 1.4 MB. "The 1.44-megabyte (MB) value associated with the 3.5-inch disk format does not represent the actual size or free space of these disks. Although its size has been popularly called 1.44 MB, the correct size is actually 1.40 MB." The 1200 KB 5½ inch diskette was marketed as 1.2 MB (1.171875 MiB) without any controversy.
CD and DVD compact disc capacities are always given in binary units. A "700 MB" (or "80 minute") CD has a nominal capacity of about 700 MiB (approx 730MB). Data capacity of CDs But DVD capacities are given in decimal units. A "4.7 GB" DVD has a nominal capacity of about 4.38 GiB. Understanding Recordable and Rewritable DVD
Buses Computer bus bandwidth is given in decimal units. This is not because hard drive capacities use the decimal versions, nor because bit rates do, but because clock speeds do. For example, "DDR SDRAM" memory runs on a Double data rate 200 MHz bus, transferring 8 bytes per cycle, and hence has a bandwidth of 200,000,000×2×8 = 3,200,000,000 byte/s.
Legal disputes There have been two significant class action lawsuits against digital storage manufactures. One case involved flash memory and the other involved hard disk drives. Both were settled with the manufactures agreeing to clarify the storage capacity of their products on the consumer packaging.
On February 20, 2004, Willem Vroegh v. Eastman Kodak Company against Lexar Media, Dane–Elec Memory, Fujifilm, Eastman Kodak Company, Kingston Technology Company, Inc., Memorex Products, Inc.; PNY Technologies Inc., SanDisk, Verbatim Corporation, and Viking InterWorks alleging that their descriptions of the capacity of their flash memory cards were false and misleading.
Vroegh claimed that a 256 MB Flash Memory Device had only 244 MB of accessible memory. "Plaintiffs allege that Defendants marketed the memory capacity of their products by assuming that one megabyte equals one million bytes and one gigabyte equals one billion bytes." The plaintiffs wanted to use the binary values 220 for megabyte and 230 for gigabyte. The plaintiffs acknowledged that the IEC and IEEE standards define a MB as one million bytes but stated that the industry has largely ignored the IEC standards.{{cite web | url = https://www.pddocs.com/FlashMemory/Documents/Vroegh%20Third%20Amended%20Complaint.pdf | title = "Vreogh Third Amended Complaint (Case No. GCG-04-428953)" | format = PDF | work = pddocs.com | publisher = Poorman-Douglas Corporation | accessdate = 2007-09-09 -->
The manufacturers agreed to clarify the flash memory card capacity on the packaging and web sites. The consumers could apply for "a discount of ten percent off a future online purchase from Defendants' Online Stores Flash Memory Device".{{cite web | last = Safier | first = Seth A. | url = https://www.pddocs.com/FlashMemory/faq.aspx | title = Frequently Asked Questions | work = Flash Memory Settlement | publisher = Poorman-Douglas Corporation | accessdate = 2007-09-09 -->The law firms Gutride Safier, LLP and Milberg Weiss received $2.4 million.
On July 7, 2005, an action entitled Orin Safier v. Western Digital Corporation, et al., was filed in the Superior Court for the City and County of San Francisco, Case No. CGC-05-442812. The case was subsequently moved to the Northern District of California, Case No. 05-03353 BZ.{{cite web | last = Gutride | first = Adam | coauthors = Seth A. Safier | date = 29 March [ | url = http://www.wdc.com/settlement/docs/complaint.htm | title = "Class Action Complaint" | work = ''Orin Safier v. Western Digital Corporation'' | publisher = [Western Digital Corporation | accessdate = 2007-09-09 -->
Although Western Digital maintained that their usage of units is consistent with "the indisputably correct industry standard for measuring and describing storage capacity", and that they "cannot be expected to reform the software industry", they agreed to settle in March 2006 with June 14, 2006 as the Final Approval hearing date.{{cite web | last = Zimmerman | first = Bernard | date = 2006 | url = http://www.wdc.com/settlement/docs/longform.htm | title = "Notice of Class Action and Proposed Settlement" | work = Orin Safier v. Western Digital Corporation | publisher = [Western Digital Corporation | accessdate = 2007-09-09 -->
Western Digital offered to compensate customers with a free download of backup and recovery software valued at US$30. They also paid $500,000 in fees and expenses to San Francisco lawyers Adam Gutride and Seth Safier, who filed the suit.
Western Digital had this footnote in their settlement. "Apparently, Plaintiff believes that he could sue an egg company for fraud for labeling a carton of 12 eggs a “dozen,” because some bakers would view a “dozen” as including 13 items."{{cite web | last = Baskin | first = Scott D. | date = 1 February [ | url = http://www.wdc.com/settlement/docs/document20.htm | title = "Defendant Western Digital Corporation's Brief in Support of Plaintiff's Motion for Preliminary Approval" | work = ''Orin Safier v. Western Digital Corporation'' | publisher = [Western Digital Corporation | accessdate = 2007-09-09 -->
The flash memory and hard disk manufacturers now have disclaimers on their packaging and web sites clarifying the formatted capacity of the flash memoryor defining MB as 1 million bytes and 1 GB as 1 billion bytes.{{cite web | url = http://www.wdc.com/en/products/Products.asp?DriveID=301 | title = "WD Caviar SE16 SATA Hard Drives" | work = Western Digital: Products | publisher = [Western Digital Corporation | accessdate = 2007-09-09 -->
Also, the Class Action Fairness Act of 2005 requires greater scrutiny on coupon settlements. One of the plaintiff law firms in the Vroegh case, Milberg Weiss & Bershad, was indicted for fraud in unrelated class action cases.{{cite web | last = Wong Yang | first = Debra | date = 18 May [ | url = http://www.usdoj.gov/usao/cac/news/pr2006/061.html | title = "Milberg Weiss Law Firm, Two Senior Partners Indicted in Secret Kickback Scheme Involving Named Plaintiffs in Class-Action Lawsuits" | work = Press Releases | publisher = [United States Department of Justice | accessdate = 2007-09-09 -->
See also
Specific units of IEC 60027-2 A.2 These units have individual articles:
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References Further reading
- — An introduction to binary prefixes
- — a 1996–1999 paper on bits, bytes, prefixes and symbols
- — Another description of binary prefixes
- — White-paper on the controversy over drive capacities
External links
- A summary of the organizations, software, and so on that have implemented the new binary prefixes
- A plea for sanity
- KiloBytes vs. kilobits vs. Kibibytes (Binary prefixes)
Converters
- SI/Binary Prefix Converter
- Decimal-to-Binary Prefixes and Binary-to-Decimal Prefixes Converter
- Tool to convert to/from the binary and standard units (up to yobibytes)
Binary prefix - Wikipedia, the free encyclopedia
In computing, binary prefixes are names or associated symbols that can precede a unit of measure (such as a byte) to indicate multiplication by a power of two.
Definitions of the SI units: The binary prefixes
It is suggested that in English, the first syllable of the name of the binary-multiple prefix should be pronounced in the same way as the first syllable of the name of the ...
Binary prefix definition of Binary prefix in the Free Online ...
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only.
prefix from FOLDOC
prefix abr decimal binary yocto- 1000^-8 zepto- 1000^-7 atto- 1000^-6 femto- f 1000^-5 pico- p 1000^-4 nano- n 1000^-3 micro- * 1000^-2 ...
libqalculate-0.9.4: BinaryPrefix Class Reference
Detailed Description A binary prefix. A Binary prefix has an integer exponent which with a base of two constitutes the value of the prefix (value=2^exponent).
Binary prefix in microsoft.public.windows.powershell
I'd like the PowerShell team to consider using binary prefixes (byte quantifiers) as they are defined by IEC to disambiguate base-2 and base-10
Prefix Compression of Sparse Binary Strings
Compressing sparse binary strings by means of common prefix. ... ACM / Crossroads / Xrds6-3 / Prefix Compression of Sparse Binary Strings
LMPBOB
Acronym Finder: LMPBOB stands for Longest-Matching Prefix Binary-Tree on Binary-Tree ... What does LMPBOB stand for? Longest-Matching Prefix Binary-Tree on Binary-Tree
INEX: Wikipedia, the free encyclopedia (Binary prefix)
Table of Contents. 1 Binary prefixes using si symbols (non-standard usage but common) 1.1. Approximate ratios between binary prefixes and their decimal equivalent
Prefix Binary-Tree on Binary-Tree - What does PBOB stand for? Acronyms ...
Acronym Definition; PBOB: Prefix Binary-Tree on Binary-Tree: PBOB: Premium Blendstock for Oxygenate Blending (gasoline production)