List of computer bus interfaces
Bus interfaces
Table:
Interface name

Year introduced

Connector

Max transfer

Main use

Notes

CAMAC
1972

Processor independent
Industry use.

S-100
1974
2×50 2.54 mm card edge

Designed around Intel 8080 but used with other processors too
Homebrew and industry use.

VME
1981
DIN 41612
10 MByte/s
Motorola 68000 based
Industry use.

STEbus
1983
DIN 41612 a+c rows
?
Processor independent based
Industrial quality bus, 8-bit data / 20-bit address. Eurocard sized.

Acorn system bus
1979
DIN 41612 a+b rows
?
6502 based
8-bit data / 16-bit address.

ISA-8
1981[1]
2×31 2.54 mm
1.99 MByte/s[2]
IBM PC
Widespread.

ISA-16
1984[3]
2×31 + 2×18 2.54 mm
3.97 MByte/s[4]
IBM AT
Widespread.

Amiga Zorro II
1985[5]
2×50 2.54 mm
3.56 MByte/s
Amiga
Auto configuration.

EISA
1988[6]

20 MByte/s
IBM clones
32-bit version of ISA-16 more or less.

NuBus
1987

40 MByte/s
NeXT, Macintosh II

Amiga Zorro III
1990[7]
2×50 2.54 mm
150 MByte/s
Amiga
Multiplexed 32-bit.

PDS
1990

Macintosh LC

PCI-32/33
1993[8]

133 MByte/s

Widespread.

PCI Express
2004[9]

250 MByte/s

P2P highspeed PCI.

VPX
2004[10]
MultiGig RT2[11]
?
Provides VMEbus-based systems with support for switched fabrics. Designed specifically with defense applications in mind. Working group is OpenVPX.
VPX computer bus standard - V -VME and P -PCI and X the extents for both buses standards.

VXI
1987[12]

160 MByte/s[13]
Multivendor standard for automated testing expansion cards. Working group is VXIConsortium.

Using the table and the supplementary paragraphs listed.

Respond to the question below: The interface that 's first home computer was called the Atom uses what sort of electrical connector ? Output only the correct answer as {"answer": "YOUR ANSWER"}. Do not introduce information beyond the provided sources.

Computer-Aided Measurement And Control ( CAMAC ) is a standard bus and modular-crate electronics standard for data acquisition and control used in particle detectors for nuclear and particle physics and in industry . The bus allows data exchange between plug-in modules ( up to 24 in a single crate ) and a crate controller , which then interfaces to a PC or to a VME-CAMAC interface . The standard was originally defined by the ESONE Committee as standard EUR 4100 in 1972 , and covers the mechanical , electrical , and logical elements of a parallel bus ( dataway ) for the plug-in modules . Several standards have been defined for multiple crate systems , including the Parallel Branch Highway definition and Serial Highway definition . Vendor-specific Host/Crate interfaces have also been built . The CAMAC standard encompasses IEEE standards :
The S-100 bus or Altair bus , IEEE696-1983 ( withdrawn ) , is an early computer bus designed in 1974 as a part of the Altair 8800 . The S-100 bus was the first industry standard expansion bus for the microcomputer industry . S-100 computers , consisting of processor and peripheral cards , were produced by a number of manufacturers . The S-100 bus formed the basis for homebrew computers whose builders ( e.g. , the Homebrew Computer Club ) implemented drivers for CP/M and MP/M . These S-100 microcomputers ran the gamut from hobbyist toy to small business workstation and were common in early home computers until the advent of the IBM PC ( which some of them outperformed ) .
The Intel 8080 ( eighty-eighty ) was the second 8-bit microprocessor designed and manufactured by Intel and was released in April 1974 . It is an extended and enhanced variant of the earlier 8008 design , although without binary compatibility . The initial specified clock rate or frequency limit was 2 MHz , and with common instructions using 4 , 5 , 7 , 10 , or 11 cycles this meant that it operated at a typical speed of a few hundred thousand instructions per second . A faster variant 8080A-1 ( Sometimes called the 8080B ) became available later with clock frequency limit up to 3.125 MHz . The 8080 needs two support chips to function in most applications , the i8224 clock generator/driver and the i8228 bus controller , and it is implemented in N-type metal-oxide-semiconductor logic ( NMOS ) using non-saturated enhancement mode transistors as loads thus demanding a +12 V and a −5 V voltage in addition to the main transistor-transistor logic ( TTL ) compatible +5 V. Although earlier microprocessors were used for calculators , cash registers , computer terminals , industrial robots , and other applications , the 8080 became one of the first widespread microprocessors . Several factors contributed to its popularity : its 40-pin package made it easier to interface than the 18-pin 8008 , and also made its data bus more efficient ; its NMOS implementation gave it faster transistors than those of the P-type metal-oxide-semiconductor logic ( PMOS ) 8008 , while also simplifying interfacing by making it TTL-compatible ; a wider variety of support chips was available ; its instruction set was enhanced over the 8008 ; and its full 16-bit address bus ( versus the 14-bit one of the 8008 ) enabled it to access 64 KB of memory , four times more than the 8008 's range of 16 KB . It became the engine of the Altair 8800 , and subsequent S-100 bus personal computers , until it was replaced by the Z80 in this role , and was the original target CPU for CP/M operating systems developed by Gary Kildall . The 8080 was successful enough that compatibility at the assembly language level became a design requirement for the Intel 8086 when its design began in 1976 , and led to the 8080 directly influencing all later variants of the ubiquitous 32-bit and 64-bit x86 architectures .
VMEbus ( Versa Module Europa or Versa Module Eurocard bus ) is a computer bus standard , originally developed for the Motorola 68000 line of CPUs , but later widely used for many applications and standardized by the IEC as ANSI/IEEE 1014-1987 . It is physically based on Eurocard sizes , mechanicals and connectors ( DIN 41612 ) , but uses its own signalling system , which Eurocard does not define . It was first developed in 1981 and continues to see widespread use today .
DIN 41612 is a DIN standard for electrical connectors that are widely used in rack based electrical systems . Standardisation of the connectors is a pre-requisite for open systems , where users expect components from different suppliers to operate together . The most widely known use of DIN 41612 connectors is in the VMEbus system . They were also used by NuBus . The standard has subsequently been upgraded to international standards IEC 60603-2 and EN 60603-2 . DIN 41612 connectors are used in Pancon , STEbus , Futurebus , VMEbus , Multibus II , NuBus , VXI Bus , eurocard TRAM motherboards , and Europe Card Bus , all of which typically use male DIN 41612 connectors on Eurocards plugged into female DIN 41612 on the backplane in a 19-inch rack chassis .
The Motorola 68000 ( 'sixty-eight-thousand ' ; also called the m68k or Motorola 68k , sixty-eight-kay ) is a 16/32-bit CISC microprocessor , introduced in 1979 by Motorola Semiconductor Products Sector . The design implements a 32-bit instruction set , with 32-bit registers and a 32-bit internal data bus . The address bus is 24-bits and does not use memory segmentation , which made it popular with programmers . Internally , it uses a 16-bit data ALU and two additional 16-bit ALUs used mostly for addresses , and has a 16-bit external data bus . For this reason , Motorola referred to it as a 16/32-bit processor . As one of the first widely available processors with a 32-bit instruction set , and running at relatively high speeds for the era , the 68k was a popular design through the 1980s . It was widely used in a new generation of personal computers with graphical user interfaces , including the Apple Macintosh , Commodore Amiga , Atari ST and many others . It competed primarily against the Intel 8088 , found in the IBM PC , which it easily outperformed . The 68k and 8088 pushed other designs , like the Zilog Z8000 and National Semiconductor 32016 , into niche markets , and made Motorola a major player in the CPU space . The 68k was soon expanded with additional family members , implementing full 32-bit ALUs as part of the growing Motorola 68000 series . The original 68k is generally software forward-compatible with the rest of the line despite being limited to a 16-bit wide external bus . After 40 years in production , the 68000 architecture is still in use .
The STEbus ( also called the IEEE-1000 bus ) is a non-proprietary , processor-independent , computer bus with 8 data lines and 20 address lines . It was popular for industrial control systems in the late 1980s and early 1990s before the ubiquitous IBM PC dominated this market . It remains a well-designed standard . Although no longer competitive in its original market , it is valid choice for hobbyists wishing to make 'home brew ' computer systems . The Z80 and probably the CMOS 65C02 would be good processors to use . The standardized bus would allow hobbyists to interface to each other 's designs .
Eurocard is a European standard format for printed circuit board ( PCB ) cards that can be plugged together into a standard chassis which , in turn , can be mounted in a 19-inch rack . The chassis consists of a series of slotted card guides on the top and bottom , into which the cards are slid so they stand on end , like books on a shelf . At the spine of each card is one or more connectors which plug into mating connectors on a backplane that closes the rear of the chassis .
The Acorn Eurocard systems were a series of modular microcomputer systems based on rack-mounted Eurocards developed by Acorn Computers from 1979 to 1982 , aimed primarily at industrial and laboratory use , but also home enthusiasts . The experience gained in developing this modular system strongly influenced the design of Acorn 's first all-in-one home computer , the Acorn Atom , released in March 1980 ; and also much of the circuitry in its successor , the BBC Micro , first shown in late 1981 . Acorn 's final rack-based machine was the System 5 , released in late 1982 . The Eurocard business was then sold on to one of its principal resellers , Control Universal Ltd , which continued to develop various cards for industrial use based on the Acorn-standard bus during the 1980s , but ultimately went into receivership in 1989 .
Industry Standard Architecture ( ISA ) is the 16-bit internal bus of IBM PC/AT and similar computers based on the Intel 80286 and its immediate successors during the 1980s . The bus was ( largely ) backward compatible with the 8-bit bus of the 8088-based IBM PC , including the IBM PC/XT as well as IBM PC compatibles . Originally referred to as the PC/AT-bus , it was also termed I/O Channel by IBM . The ISA term was coined as a retronym by competing PC-clone manufacturers in the late 1980s or early 1990s as a reaction to IBM attempts to replace the AT-bus with its new and incompatible Micro Channel architecture . The 16-bit ISA bus was also used with 32-bit processors for several years . An attempt to extend it to 32 bits , called Extended Industry Standard Architecture ( EISA ) , was not very successful , however . Later buses such as VESA Local Bus and PCI were used instead , often along with ISA slots on the same mainboard . Derivatives of the AT bus structure were and still are used in ATA/IDE , the PCMCIA standard , Compact Flash , the PC/104 bus , and internally within Super I/O chips .
The IBM Personal Computer , commonly known as the IBM PC , is the original version of the IBM PC compatible hardware platform . It is IBM model number 5150 and was introduced on August 12 , 1981 . It was created by a team of engineers and designers under the direction of Philip Don Estridge of the IBM Entry Systems Division in Boca Raton , Florida . The generic term personal computer ( PC ) was in use years before 1981 , applied as early as 1972 to the Xerox PARC 's Alto , but the term PC came to mean more specifically a desktop microcomputer compatible with IBM 's Personal Computer branded products . The machine was based on open architecture , and third-party suppliers sprang up to provide peripheral devices , expansion cards , and software . IBM had a substantial influence on the personal computer market in standardizing a platform for personal computers , and IBM compatible became an important criterion for sales growth . Only the Apple Macintosh family kept a significant share of the microcomputer market after the 1980s without compatibility to the IBM personal computer .
The IBM Personal Computer AT , more commonly known as the IBM AT and also sometimes called the PC AT or PC/AT , was IBM 's second-generation PC , designed around the 6 MHz Intel 80286 microprocessor and released in 1984 as System Unit 5170 . The name AT stood for Advanced Technology , and was chosen because the AT offered various technologies that were then new in personal computers ; one such advancement was that the 80286 processor supported protected mode . IBM later released an 8 MHz version of the AT .
Zorro II is the general purpose expansion bus used by the Amiga 2000 computer . The bus is mainly a buffered extension of the Motorola 68000 bus , with support for bus mastering DMA . The expansion slots use a 100-pin connector and the card form factor is the same as the IBM PC . Zorro II cards implement the Autoconfig protocol for automatic address space assignment ( designed before , yet similar to , Plug and Play on the PC ) . The prototype Zorro bus expansion box for the Amiga 1000 was the basis for the initial Amiga 2000-A model design . This box connected to the Amiga 1000 unbuffered CPU bus card edge connector . Zorro II was succeeded by Zorro III , a 32-bit , asynchronous bus .
The Amiga is a family of personal computers introduced by Commodore in 1985 . The original model was part of a series of 16/32- and 32-bit computers that featured 256 KB or more of RAM , mouse-based GUIs , and significantly improved graphics and audio over 8-bit systems . This wave included the Atari ST - released the same year - Apple 's Macintosh , and later the Apple IIGS . Based on the Motorola 68000 microprocessor , the Amiga differed from its contemporaries through the inclusion of custom hardware to accelerate graphics and sound , including sprites and a blitter , and a pre-emptive multitasking operating system called AmigaOS . The Amiga 1000 was released in July 1985 , but a series of production problems kept it from becoming widely available until early 1986 . The best selling model , the Amiga 500 , was introduced in 1987 and became one of the leading home computers of the late 1980s and early 1990s with four to six million sold . The A3000 was introduced in 1990 , followed by the A500+ , and the A600 in March 1992 . Finally , the A1200 and the A4000 were released in late 1992 . The platform became particularly popular for gaming and programming demos . It also found a prominent role in the desktop video , video production , and show control business , leading to video editing systems such as the Video Toaster . The Amiga 's native ability to simultaneously play back multiple digital sound samples made it a popular platform for early tracker music software . The relatively powerful processor and ability to access several megabytes of memory enabled the development of 3D rendering packages , including LightWave 3D , Imagine , Aladdin4D , TurboSilver and Traces , a predecessor to Blender .
The Extended Industry Standard Architecture ( in practice almost always shortened to EISA and frequently pronounced eee-suh ) is a bus standard for IBM PC compatible computers . It was announced in September 1988 by a consortium of PC clone vendors ( the Gang of Nine ) as a counter to IBM 's use of its proprietary Micro Channel architecture ( MCA ) in its PS/2 series . In comparison with the AT bus , which the Gang of Nine retroactively renamed to the ISA bus to avoid infringing IBM 's trademark on its PC/AT computer , EISA is extended to 32 bits and allows more than one CPU to share the bus . The bus mastering support is also enhanced to provide access to 4 GB of memory . Unlike MCA , EISA can accept older XT and ISA boards - the lines and slots for EISA are a superset of ISA . EISA was much favoured by manufacturers due to the proprietary nature of MCA , and even IBM produced some machines supporting it . It was somewhat expensive to implement ( though not as much as MCA ) , so it never became particularly popular in desktop PCs . However , it was reasonably successful in the server market , as it was better suited to bandwidth-intensive tasks ( such as disk access and networking ) . Most EISA cards produced were either SCSI or network cards . EISA was also available on some non-IBM-compatible machines such as the AlphaServer , HP 9000-D , SGI Indigo2 and MIPS Magnum . By the time there was a strong market need for a bus of these speeds and capabilities for desktop computers , the VESA Local Bus and later PCI filled this niche , and EISA vanished into obscurity .
IBM PC compatible computers are similar to the original IBM PC , XT , and AT that are able to use the same software and expansion cards . Such computers were referred to as PC clones , or IBM clones . The term IBM PC compatible is now a historical description only , since IBM no longer sells personal computers . The industry jargon PC sometimes does n't mean personal computer generally , but rather a computer running Microsoft Windows , in contrast to Apple 's Mac . These clones duplicate almost exactly all the significant features of the IBM PC architecture . This was facilitated by IBM 's choice of commodity hardware components and by various manufacturers ' ability to reverse engineer the BIOS firmware using a clean room design technique . Columbia Data Products built the first clone of the IBM personal computer by a clean room implementation of its BIOS . [ citation needed ] Early IBM PC compatibles used the same computer bus as the original PC and AT models . The IBM AT compatible bus was later named the Industry Standard Architecture ( ISA ) bus by manufacturers of compatible computers . Descendants of the IBM PC compatibles comprise the majority of personal computers on the market presently , with the dominant operating system being Microsoft Windows , although interoperability with the bus structure and peripherals of the original PC architecture may be limited or non-existent . Some of these computers ran MS-DOS but had enough hardware differences that IBM compatible software could not be used ; examples include slight differences in the memory map , serial ports or video hardware . Only the Macintosh kept significant market share without having compatibility with the IBM PC .
NuBus ( pron . 'New Bus ' ) is a 32-bit parallel computer bus , originally developed at MIT and standardized in 1987 as a part of the NuMachine workstation project . The first complete implementation of the NuBus was done by Western Digital for their NuMachine , and for the Lisp Machines Inc. LMI Lambda . The NuBus was later incorporated in Lisp products by Texas Instruments ( Explorer ) , and used as the main expansion bus by Apple Computer and NeXT . It is no longer widely used outside the embedded market .
NeXT , Inc. ( later NeXT Computer , Inc. and NeXT Software , Inc. ) was an American computer and software company founded in 1985 by Apple Computer co-founder Steve Jobs . Its name was usually pronounced as Next . Based in Redwood City , California , the company developed and manufactured a series of computer workstations intended for the higher education and business markets . NeXT was founded by Jobs after he was fired from Apple , along with several co-workers . NeXT introduced the first NeXT Computer in 1988 , and the smaller NeXTstation in 1990 . The NeXT computers experienced relatively limited sales , with estimates of about 50,000 units shipped in total . Nevertheless , their innovative object-oriented NeXTSTEP operating system and development environment ( Interface Builder ) were highly influential . The first major outside investment was from Ross Perot , who invested after seeing a segment about NeXT on The Entrepreneurs . In 1987 , he invested $ 20 million in exchange for 16 percent of NeXT 's stock and subsequently joined the board of directors in 1988 . NeXT later released much of the NeXTSTEP system as a programming environment standard called OpenStep . NeXT withdrew from the hardware business in 1993 to concentrate on marketing OPENSTEP for Mach , its own OpenStep implementation , for several original equipment manufacturers ( OEMs ) . NeXT also developed WebObjects , one of the first enterprise web application frameworks .
The Macintosh II is a personal computer designed , manufactured and sold by Apple Computer , Inc. from March 1987 to January 1990 . It is the first model of the Macintosh II family , and the first Macintosh to support a color display . When first introduced , a basic system with 20 MB drive and monitor cost US $ 5,498 ( equivalent to $ 12,373 in 2019 ) . With a 13-inch color monitor and 8-bit display card the price was around US $ 7,145 ( equivalent to $ 16,079 in 2019 ) . This price placed it in competition with workstations from Silicon Graphics , Sun Microsystems , and Hewlett-Packard . The Macintosh II was designed by hardware engineers Michael Dhuey ( computer ) and Brian Berkeley ( monitor ) and industrial designer Hartmut Esslinger ( case ) . Eighteen months after its introduction , the Macintosh II was updated with a more powerful CPU and sold as the Macintosh IIx . In early 1989 , the more compact Macintosh IIcx was introduced at a price similar to the original Macintosh II , and by the beginning of 1990 sales stopped altogether . Motherboard upgrades to turn a Macintosh II into a IIx or Macintosh IIfx were offered by Apple .
Released as the expansion bus of the Commodore Amiga 3000 in 1990 , the Zorro III computer bus was used to attach peripheral devices to an Amiga motherboard . Designed by Commodore International lead engineer Dave Haynie , the 32-bit Zorro III replaced the 16-bit Zorro II bus used in the Amiga 2000 . As with the Zorro II bus , Zorro III allowed for true Plug and Play autodetection ( similar to , and prior to , the PC 's PCI bus ) wherein devices were dynamically allocated the resources they needed on boot . Zorro III continued Zorro II 's direct memory-mapped address design ( unlike 80x86 processors , the MC68K family used in the Amiga did not have a separate I/O address mechanism ) . Just as with Zorro II on 24-bit systems , Zorro III reserved a large chunk of 32-bit real memory address space for large memory mapped cards , a smaller chunk with smaller allocation granularity for I/O type board . Zorro III was never supported on 24-bit address or 16-bit data devices - it required a full 32-bit CPU . The CPU could directly address any Zorro III device as memory , so Zorro memory expansions could be made ( and were made ) as well as it being possible to use video memory on a video card to be as system RAM . As an asynchronous bus , Zorro III specified bus cycles of set lengths during which a transaction conforming to the specifications of the bus could be carried out . The initial implementation of Zorro III was in Commodore 's Fat Buster ( BUS conTrollER ) gate array , assisted by a very high speed PAL and numerous TTL buffer chips for bus buffering , isolation , and multiplexing . The Amiga 4000 implementation was fundamentally the same , but integrated a second gate-array to replace the TTL buffers . The Buster chip provided bus arbitration , translation between the MC68030 bus protocols and either Zorro II or Zorro III bus cycles ( geographically mapped based on the Zorro bus address ) , and a vectored interrupt mechanism , generally not used . Zorro II bus masters were legal bus hogs , but Zorro III devices were fairly arbitrated and had controller-limited bus tenure .
The Processor Direct Slot or PDS , introduced by Apple Computer , in several of their Macintosh models , provided a limited measure of hardware expandability , without going to the expense ( in terms of desk space as well as selling price ) of providing full-fledged bus expansion slots . Typically , a machine would feature multiple bus expansions slots , if any . However , there was never more than one PDS slot . Rather than providing a sophisticated communication protocol with arbitration between different bits of hardware that might be trying to use the communication channel at the same time , the PDS slot , for the most part , just gave direct access to signal pins on the CPU , making it closer in nature to a local bus . Thus , PDS slots tended to be CPU-specific , and therefore a card designed for the PDS slot in the Motorola 68030-based Macintosh SE/30 , for example , would not work in the Motorola 68040-based Quadra 700 . The one notable exception to this was the PDS design for the original Motorola 68020-based Macintosh LC . This was Apple 's first attempt at a low-cost Mac , and it was such a success that , when subsequent models replaced the CPU with a 68030 , a 68040 , and later a PowerPC processor , Apple found methods to keep the PDS slot compatible with the original LC , so that the same expansion cards would continue to work .
The Macintosh LC is a personal computer designed , manufactured , and sold by Apple Computer , Inc. from October 1990 to March 1992 .
Conventional PCI , often shortened to PCI , is a local computer bus for attaching hardware devices in a computer . PCI is an abbreviation for Peripheral Component Interconnect and is part of the PCI Local Bus standard . The PCI bus supports the functions found on a processor bus but in a standardized format that is independent of any particular processor 's native bus . Devices connected to the PCI bus appear to a bus master to be connected directly to its own bus and are assigned addresses in the processor 's address space . It is a parallel bus , synchronous to a single bus clock . Attached devices can take either the form of an integrated circuit fitted onto the motherboard itself ( called a planar device in the PCI specification ) or an expansion card that fits into a slot . The PCI Local Bus was first implemented in IBM PC compatibles , where it displaced the combination of several slow ISA slots and one fast VESA Local Bus slot as the bus configuration . It has subsequently been adopted for other computer types . Typical PCI cards used in PCs include : network cards , sound cards , modems , extra ports such as USB or serial , TV tuner cards and disk controllers . PCI video cards replaced ISA and VESA cards until growing bandwidth requirements outgrew the capabilities of PCI . The preferred interface for video cards then became AGP , itself a superset of PCI , before giving way to PCI Express . The first version of PCI found in retail desktop computers was a 32-bit bus using a 33 MHz bus clock and 5 V signalling , although the PCI 1.0 standard provided for a 64-bit variant as well .
PCI Express ( Peripheral Component Interconnect Express ) , officially abbreviated as PCIe or PCI-e , is a high-speed serial computer expansion bus standard , designed to replace the older PCI , PCI-X and AGP bus standards . It is the common motherboard interface for personal computers ' graphics cards , hard drives , SSDs , Wi-Fi and Ethernet hardware connections . PCIe has numerous improvements over the older standards , including higher maximum system bus throughput , lower I/O pin count and smaller physical footprint , better performance scaling for bus devices , a more detailed error detection and reporting mechanism ( Advanced Error Reporting , AER ) , and native hot-swap functionality . More recent revisions of the PCIe standard provide hardware support for I/O virtualization . Defined by its number of lanes , the PCI Express electrical interface is also used in a variety of other standards , most notably the laptop expansion card interface ExpressCard and computer storage interfaces SATA Express , U.2 ( SFF-8639 ) and M.2 . Format specifications are maintained and developed by the PCI-SIG ( PCI Special Interest Group ) , a group of more than 900 companies that also maintain the conventional PCI specifications .
In telecommunications , a point-to-point connection refers to a communications connection between two communication endpoints or nodes . An example is a telephone call , in which one telephone is connected with one other , and what is said by one caller can only be heard by the other . This is contrasted with a point-to-multipoint or broadcast connection , in which many nodes can receive information transmitted by one node . Other examples of point-to-point communications links are leased lines and microwave radio relay . The term is also used in computer networking and computer architecture to refer to a wire or other connection that links only two computers or circuits , as opposed to other network topologies such as buses or crossbar switches which can connect many communications devices . Point-to-point is sometimes abbreviated as P2P . This usage of P2P is distinct from P2P meaning peer-to-peer in the context of file sharing networks .
VPX technology was presented at Bus & Board ( VITA ) in 2004 . VPX , formally known as VITA 46 , is an ANSI standard ( ANSI/VITA 46.0-2007 ) that provides VMEbus-based systems with support for switched fabrics over a new high speed connector . Defined by the VITA ( VME International Trade Association ) working group ( composed of companies such as Abaco Systems , ADLINK , Aitech , Boeing , Curtiss-Wright , Elma Electronic , Extreme Engineering Solutions , Inc. ( X-ES ) , GE Intelligent Platforms , General Micro Systems , Inc. ( GMS ) , Kontron , Mercury Computer Systems , Pentek , Cornet Technology , Inc. , and Northrop Grumman ) , it has been designed specifically with defense applications in mind , with an enhanced module standard that enables applications and platforms with superior performance . VPX retains VME 's existing 6U and 3U Eurocard form factors , supporting existing PCI Mezzanine Card ( PMC ) and XMC mezzanines ( PMC with high-speed serial fabric interconnect ) , and maintaining the maximum possible compatibility with VMEbus . New generations of embedded systems based on the VPX standard reflect the growing significance of high speed serial switched fabric interconnects such as PCI Express , RapidIO , Infiniband and 10 Gigabit Ethernet . These technologies are replacing traditional parallel communications bus architectures for local communications , because they offer significantly greater capability . Switched fabrics technology supports the implementation of multiprocessing systems that require the fastest possible communications between multiple processors ( e.g. , digital signal processing applications ) . VPX gives the large existing base of VMEbus users access to these switched fabrics .
Switched Fabric or switching fabric is a network topology in which network nodes interconnect via one or more network switches ( particularly crossbar switches ) . Because a switched fabric network spreads network traffic across multiple physical links , it yields higher total throughput than broadcast networks , such as the early 10BASE5 version of Ethernet , or most wireless networks such as Wi-Fi . The generation of high-speed serial data interconnects that appeared in 2001-2004 which provided point-to-point connectivity between processor and peripheral devices are sometimes referred to as fabrics ; however , they lack features such as a message passing protocol . [ citation needed ] For example , HyperTransport , the computer processor interconnect technology , continues to maintain a processor bus focus even after adopting a higher speed physical layer . Similarly , PCI Express is just a serial version of PCI ; it adheres to PCIs host/peripheral load/store direct memory access ( DMA ) -based architecture on top of a serial physical and link layer .
OpenVPX is an Industry Working Group of 28 defense contractors . OpenVPX was founded by Mercury Systems in January 2009 . The OpenVPX Industry Working Group has provided new standards which will replace VME and VXS standards in future defense designs . On October 19 , 2009 , the OpenVPX working group demonstrated the new standard at MILCOM featuring an OpenVPX backplane in a Hybricon SFF-4 Small Form Factor conduction-cooled chassis integrated with Curtiss-Wright Controls ' small form factor 3U OpenVPX-compliant cards . OpenVPX is a fully ratified open standard in the VITA ( VMEbus International Trade Association ) organization . ANSI/VITA 65-2017 is the OpenVPX System Standard with several related specifications for ruggedized mechanical implementation , RF signal interconnects , optical interconnects , and more . There is a wide ecosystem of board and system/chassis vendors including Pixus Technologies , Elma Electronic , GE Intelligent Platforms , Concurrent Technologies , CoreEL Technologies Kontron , Mercury Systems , and many others .
The VXI bus architecture is an open standard platform for automated test based upon VMEbus . VXI stands for VME eXtensions for Instrumentation , defining additional bus lines for timing and triggering as well as mechanical requirements and standard protocols for configuration , message-based communication , multi-chassis extension , and other features . In 2004 , the 2eVME extension was added to the VXI bus specification , giving it a maximum data rate of 160 MB/s . The basic building block of a VXI system is the mainframe or chassis . This contains up to 13 slots into which various modules ( instruments ) can be added . The mainframe also contains all the power supply requirements for the rack and the instruments it contains . Instruments in the form of VXI Modules then fit the slots in the rack . VXI bus modules are typically 6U in height ( see Eurocard ) and C-size ( unlike VME bus modules which are more commonly B-size ) . It is therefore possible to configure a system to meet a particular requirement by selecting the required instruments . The basic architecture of the instrument system is described in US Patent 4,707,834 . This Patent was freely licensed by Tektronix to the VXIbus Consortium . The VXIbus grew from the VME bus specification , it was established in 1987 by Hewlett Packard ( now Keysight Technologies ) , Racal Instruments ( now Astronics Test Systems ) , Colorado Data Systems , Wavetek and Tektronix .