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64-613: Almost all network operating systems support PPP with PAP, as do most network access servers . PAP is also used in PPPoE , for authenticating DSL users. As the Point-to-Point Protocol (PPP) sends data unencrypted and "in the clear", PAP is vulnerable to any attacker who can observe the PPP session. An attacker can see the users name, password, and any other information associated with the PPP session. Some additional security can be gained on

128-467: A network and can print at speeds of 45 to around 100 ppm. The Xerox 9700 could achieve 120 ppm. An ID Card printer is used for printing plastic ID cards. These can now be customised with important features such as holographic overlays, HoloKotes and watermarks. This is either a direct to card printer (the more feasible option) or a retransfer printer. A virtual printer is a piece of computer software whose user interface and API resembles that of

192-451: A printer is a peripheral machine which makes a durable representation of graphics or text, usually on paper . While most output is human-readable, bar code printers are an example of an expanded use for printers. Different types of printers include 3D printers, inkjet printers, laser printers, and thermal printers. The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his difference engine in

256-427: A printer or a large and expensive hard disk . As local area network technology became available, two general approaches to handle sharing of resources on networks arose. Historically, a network operating system was an operating system for a computer which implemented network capabilities. Operating systems with a network stack allowed personal computers to participate in a client-server architecture in which

320-662: A server enables multiple clients to share resources, such as printers . Early examples of client-server operating systems that were shipped with fully integrated network capabilities are Novell NetWare using the Internetwork Packet Exchange (IPX) network protocol and Banyan VINES which used a variant of the Xerox Network Systems (XNS) protocols. These limited client/server networks were gradually replaced by Peer-to-peer networks, which used networking capabilities to share resources and files located on

384-454: A typewriter ), or, less commonly, hits the back of the paper, pressing the paper against the ink ribbon (the IBM 1403 for example). All but the dot matrix printer rely on the use of fully formed characters , letterforms that represent each of the characters that the printer was capable of printing. In addition, most of these printers were limited to monochrome, or sometimes two-color, printing in

448-406: A typewriter . A hammer strikes a wheel with petals, the "daisy wheel", each petal containing a letter form at its tip. The letter form strikes a ribbon of ink , depositing the ink on the page and thus printing a character. By rotating the daisy wheel, different characters are selected for printing. These printers were also referred to as letter-quality printers because they could produce text which

512-486: A xerographic printing process but differ from analog photocopiers in that the image is produced by the direct scanning of a laser beam across the printer's photoreceptor . Another toner-based printer is the LED printer which uses an array of LEDs instead of a laser to cause toner adhesion to the print drum. Inkjet printers operate by propelling variably sized droplets of liquid ink onto almost any sized page. They are

576-466: A PPP frame. The protocol field has a value of C023 (hex). Network operating system A network operating system ( NOS ) is a specialized operating system for a network device such as a router , switch or firewall. Historically operating systems with networking capabilities were described as network operating systems, because they allowed personal computers (PCs) to participate in computer networks and shared file and printer access within

640-415: A brochure. As of the 2020s, 3D printing has become a widespread hobby due to the abundance of cheap 3D printer kits, with the most common process being Fused deposition modeling . Personal printers are mainly designed to support individual users, and may be connected to only a single computer. These printers are designed for low-volume, short-turnaround print jobs , requiring minimal setup time to produce

704-407: A chemical coated paper, which is charged by the print head according to the image of the document. The paper is passed near a pool of liquid ink with the opposite charge. The charged areas of the paper attract the ink and thus form the image. This process was developed from the process of electrostatic copying . Color reproduction is very accurate, and because there is no heating the scale distortion

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768-445: A cheque must be printed using MICR toner or ink. Banks and other clearing houses employ automation equipment that relies on the magnetic flux from these specially printed characters to function properly. The following printing technologies are routinely found in modern printers: A laser printer rapidly produces high quality text and graphics. As with digital photocopiers and multifunction printers (MFPs), laser printers employ

832-444: A company does not already have a local (or network) printer that has the features they need, then the web-based option is a perhaps a more affordable solution. The web-based solution is good for small businesses that do not anticipate a lot of rapid growth, or organizations who either can not afford a card printer, or do not have the resources to learn how to set up and use one. Generally speaking, desktop-based solutions involve software,

896-645: A considerable increase in durability and a greater degree of counterfeit prevention. Some card printers come with an option to print both sides at the same time, which cuts down the time taken to print and less margin of error. In such printers one side of id card is printed and then the card is flipped in the flip station and other side is printed. Alongside the traditional uses in time attendance and access control (in particular with photo personalization), countless other applications have been found for plastic cards, e.g. for personalized customer and members' cards, for sports ticketing and in local public transport systems for

960-449: A database (or spreadsheet) and can be installed on a single computer or network. Alongside the basic function of printing cards, card printers can also read and encode magnetic stripes as well as contact and contact free RFID chip cards ( smart cards ). Thus card printers enable the encoding of plastic cards both visually and logically. Plastic cards can also be laminated after printing. Plastic cards are laminated after printing to achieve

1024-466: A detailed description of many of the technologies used. Several different computer printers were simply computer-controllable versions of existing electric typewriters. The Friden Flexowriter and IBM Selectric-based printers were the most-common examples. The Flexowriter printed with a conventional typebar mechanism while the Selectric used IBM's well-known "golf ball" printing mechanism. In either case,

1088-443: A hard copy of a given document. They are generally slow devices ranging from 6 to around 25 pages per minute (ppm), and the cost per page is relatively high. However, this is offset by the on-demand convenience. Some printers can print documents stored on memory cards or from digital cameras and scanners . Networked or shared printers are "designed for high-volume, high-speed printing". They are usually shared by many users on

1152-527: A layer of ink on paper. A card printer is an electronic desktop printer with single card feeders which print and personalize plastic cards . In this respect they differ from, for example, label printers which have a continuous supply feed. Card dimensions are usually 85.60 × 53.98 mm, standardized under ISO/IEC 7810 as ID-1. This format is also used in EC-cards , telephone cards , credit cards , driver's licenses and health insurance cards . This

1216-415: A local area network (LAN). This description of operating systems is now largely historical, as common operating systems include a network stack to support a client–server model. Early microcomputer operating systems such as CP/M , MS-DOS and classic Mac OS were designed for one user on one computer. Packet switching networks were developed to share hardware resources, such as a mainframe computer ,

1280-537: A period during the early home computer era when a range of printers were manufactured under many brands such as the Commodore VIC-1525 using the Seikosha Uni-Hammer system. This used a single solenoid with an oblique striker that would be actuated 7 times for each column of 7 vertical pixels while the head was moving at a constant speed. The angle of the striker would align the dots vertically even though

1344-593: A printer driver, but which is not connected with a physical computer printer. A virtual printer can be used to create a file which is an image of the data which would be printed, for archival purposes or as input to another program, for example to create a PDF or to transmit to another system or user. A barcode printer is a computer peripheral for printing barcode labels or tags that can be attached to, or printed directly on, physical objects. Barcode printers are commonly used to label cartons before shipment, or to label retail items with UPCs or EANs . A 3D printer

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1408-468: A printer on their network that is capable of printing identification cards. If a business already owns an ID card printer, then a desktop-based badge maker is probably suitable for their needs. Typically, large organizations who have high employee turnover will have their own printer. A desktop-based badge maker is also required if a company needs their IDs make instantly. An example of this is the private construction site that has restricted access. However, if

1472-512: A single building, the Internet protocol suite became almost universally adopted in network architectures. Thereafter, computer operating systems and the firmware of network devices tended to support Internet protocols. Network operating systems can be embedded in a router or hardware firewall that operates the functions in the network layer ( layer 3 ). Notable network operating systems include: Printer (computing) In computing ,

1536-402: A single horizontal series of pixels across the page), referring to the configuration of the print head. In the 1970s and '80s, dot matrix printers were one of the more common types of printers used for general use, such as for home and small office use. Such printers normally had either 9 or 24 pins on the print head (early 7 pin printers also existed, which did not print descenders ). There was

1600-501: A single typeface at one time, although bolding and underlining of text could be done by "overstriking", that is, printing two or more impressions either in the same character position or slightly offset. Impact printers varieties include typewriter-derived printers, teletypewriter-derived printers, daisywheel printers, dot matrix printers, and line printers. Dot-matrix printers remain in common use in businesses where multi-part forms are printed. An overview of impact printing contains

1664-483: A variety of computers of all sizes. A peer-to-peer network sets all connected computers equal; they all share the same abilities to use resources available on the network. The most popular peer-to-peer networks as of 2020 are Ethernet , Wi-Fi and the Internet protocol suite . Software that allowed users to interact with these networks, despite a lack of networking support in the underlying manufacturer's operating system,

1728-403: Is Zink (a portmanteau of "zero ink"). The following technologies are either obsolete, or limited to special applications though most were, at one time, in widespread use. Impact printers rely on a forcible impact to transfer ink to the media. The impact printer uses a print head that either hits the surface of the ink ribbon, pressing the ink ribbon against the paper (similar to the action of

1792-406: Is a device for making a three-dimensional object from a 3D model or other electronic data source through additive processes in which successive layers of material (including plastics, metals, food, cement, wood, and other materials) are laid down under computer control. It is called a printer by analogy with an inkjet printer which produces a two-dimensional document by a similar process of depositing

1856-561: Is commonly known as the bank card format. Card printers are controlled by corresponding printer drivers or by means of a specific programming language. Generally card printers are designed with laminating, striping, and punching functions, and use desktop or web-based software. The hardware features of a card printer differentiate a card printer from the more traditional printers, as ID cards are usually made of PVC plastic and require laminating and punching. Different card printers can accept different card thickness and dimensions. The principle

1920-438: Is computationally infeasible to reverse the function to recover a plaintext password. As a result, while PAP passwords are less secure when sent over a PPP link, they allow for more secure storage "at rest" than with other methods such as CHAP . PAP authentication is only done at the time of the initial link establishment, and verifies the identity of the client using a two-way handshake . Description PAP packet embedded in

1984-606: Is less than ±0.1%. (All laser printers have an accuracy of ±1%.) Worldwide, most survey offices used this printer before color inkjet plotters become popular. Liquid ink electrostatic printers were mostly available in 36 to 54 inches (910 to 1,370 mm) width and also 6 color printing. These were also used to print large billboards. It was first introduced by Versatec, which was later bought by Xerox . 3M also used to make these printers. Pen-based plotters were an alternate printing technology once common in engineering and architectural firms. Pen-based plotters rely on contact with

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2048-474: Is often forgotten is resistance to alteration: liquid ink , such as from an inkjet head or fabric ribbon, becomes absorbed by the paper fibers, so documents printed with liquid ink are more difficult to alter than documents printed with toner or solid inks, which do not penetrate below the paper surface. Cheques can be printed with liquid ink or on special cheque paper with toner anchorage so that alterations may be detected. The machine-readable lower portion of

2112-506: Is the same for practically all card printers: the plastic card is passed through a thermal print head at the same time as a color ribbon. The color from the ribbon is transferred onto the card through the heat given out from the print head. The standard performance for card printing is 300 dpi (300 dots per inch, equivalent to 11.8 dots per mm). There are different printing processes, which vary in their detail: Broadly speaking there are three main types of card printers, differing mainly by

2176-541: The Berkeley Software Distribution . Today, distributed computing and groupware applications have become the norm. Computer operating systems include a networking stack as a matter of course. During the 1980s the need to integrate dissimilar computers with network capabilities grew and the number of networked devices grew rapidly. Partly because it allowed for multi-vendor interoperability , and could route packets globally rather than being restricted to

2240-401: The 1990s and into the 2000s has largely displaced the need for printing as a means of moving documents, and a wide variety of reliable storage systems means that a "physical backup" is of little benefit today. Starting around 2010, 3D printing became an area of intense interest, allowing the creation of physical objects with the same sort of effort as an early laser printer required to produce

2304-417: The 19th century; however, his mechanical printer design was not built until 2000. The first patented printing mechanism for applying a marking medium to a recording medium or more particularly an electrostatic inking apparatus and a method for electrostatically depositing ink on controlled areas of a receiving medium, was in 1962 by C. R. Winston, Teletype Corporation, using continuous inkjet printing. The ink

2368-458: The PPP link by using CHAP or EAP . However, there are always tradeoffs when choosing an authentication method, and there is no single answer for which is more secure. When PAP is used in PPP, it is considered a weak authentication scheme. Weak schemes are simpler and have lighter computational overhead than more complex schemes such as Transport Layer Security (TLS), but they are much more vulnerable to attack. While weak schemes are used where

2432-452: The X- and Y-axes, by a mechanism, and the selected letter form was struck by a hammer. Others used a type cylinder in a similar way as the Selectric typewriters used their type ball. In either case, the letter form then struck a ribbon to print the letterform. Most teleprinters operated at ten characters per second although a few achieved 15 CPS. Daisy wheel printers operate in much the same fashion as

2496-410: The development of new systems specifically for computer use. In the 1980s there were daisy wheel systems similar to typewriters, line printers that produced similar output but at much higher speed, and dot-matrix systems that could mix text and graphics but produced relatively low-quality output. The plotter was used for those requiring high-quality line art like blueprints . The introduction of

2560-401: The end of the twentieth century. Line printers print an entire line of text at a time. Four principal designs exist. In each case, to print a line, precisely timed hammers strike against the back of the paper at the exact moment that the correct character to be printed is passing in front of the paper. The paper presses forward against a ribbon which then presses against the character form and

2624-437: The head had moved one dot spacing in the time. The vertical dot position was controlled by a synchronized longitudinally ribbed platen behind the paper that rotated rapidly with a rib moving vertically seven dot spacings in the time it took to print one pixel column. 24-pin print heads were able to print at a higher quality and started to offer additional type styles and were marketed as Near Letter Quality by some vendors. Once

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2688-468: The impression of the character form is printed onto the paper. Each system could have slight timing issues, which could cause minor misalignment of the resulting printed characters. For drum or typebar printers, this appeared as vertical misalignment, with characters being printed slightly above or below the rest of the line. In chain or bar printers, the misalignment was horizontal, with printed characters being crowded closer together or farther apart. This

2752-405: The letter form then struck a ribbon which was pressed against the paper, printing one character at a time. The maximum speed of the Selectric printer (the faster of the two) was 15.5 characters per second. The common teleprinter could easily be interfaced with the computer and became very popular except for those computers manufactured by IBM . Some models used a "typebox" that was positioned, in

2816-615: The liquid ink on a rotating, oil coated drum. The paper then passes over the print drum, at which time the image is immediately transferred, or transfixed, to the page. Solid ink printers are most commonly used as color office printers and are excellent at printing on transparencies and other non-porous media. Solid ink is also called phase-change or hot-melt ink and was first used by Data Products and Howtek, Inc., in 1984. Solid ink printers can produce excellent results with text and images. Some solid ink printers have evolved to print 3D models, for example, Visual Impact Corporation of Windham, NH

2880-591: The low-cost laser printer in 1984, with the first HP LaserJet , and the addition of PostScript in next year's Apple LaserWriter set off a revolution in printing known as desktop publishing . Laser printers using PostScript mixed text and graphics, like dot-matrix printers, but at quality levels formerly available only from commercial typesetting systems. By 1990, most simple printing tasks like fliers and brochures were now created on personal computers and then laser printed; expensive offset printing systems were being dumped as scrap. The HP Deskjet of 1988 offered

2944-400: The method used to print onto the card. They are: Different ID Card Printers use different encoding techniques to facilitate disparate business environments and to support security initiatives. Known encoding techniques are: There are basically two categories of card printer software: desktop-based, and web-based (online). The biggest difference between the two is whether or not a customer has

3008-463: The most common type of computer printer used by consumers. Solid ink printers, also known as phase-change ink or hot-melt ink printers, are a type of thermal transfer printer , graphics sheet printer or 3D printer . They use solid sticks, crayons, pearls or granular ink materials. Common inks are CMYK -colored ink, similar in consistency to candle wax, which are melted and fed into a piezo crystal operated print-head. A Thermal transfer printhead jets

3072-464: The other hand, the mechanical components of line printers operate with tight tolerances and require regular preventive maintenance (PM) to produce a top quality print. They are virtually never used with personal computers and have now been replaced by high-speed laser printers . The legacy of line printers lives on in many operating systems , which use the abbreviations "lp", "lpr", or "LPT" to refer to printers. Liquid ink electrostatic printers use

3136-639: The paper (but not impact, per se) and special purpose pens that are mechanically run over the paper to create text and images. Since the pens output continuous lines, they were able to produce technical drawings of higher resolution than was achievable with dot-matrix technology. Some plotters used roll-fed paper, and therefore had a minimal restriction on the size of the output in one dimension. These plotters were capable of producing quite sizable drawings. A number of other sorts of printers are important for historical reasons, or for special purpose uses. Printers can be connected to computers in many ways: directly by

3200-399: The pressure of the print head to be applied to a stack of two or more forms to print multi-part documents such as sales invoices and credit card receipts using continuous stationery with carbonless copy paper . It also has security advantages as ink impressed into a paper matrix by force is harder to erase invisibly. Dot-matrix printers were being superseded even as receipt printers after

3264-506: The price of inkjet printers dropped to the point where they were competitive with dot matrix printers, dot matrix printers began to fall out of favour for general use. Some dot matrix printers, such as the NEC P6300, can be upgraded to print in color. This is achieved through the use of a four-color ribbon mounted on a mechanism (provided in an upgrade kit that replaces the standard black ribbon mechanism after installation) that raises and lowers

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3328-462: The printing business to Xerox in 2001. A dye-sublimation printer (or dye-sub printer) is a printer that employs a printing process that uses heat to transfer dye to a medium such as a plastic card , paper, or canvas . The process is usually to lay one color at a time using a ribbon that has color panels. Dye-sub printers are intended primarily for high-quality color applications, including color photography; and are less well-suited for text. While once

3392-463: The production of season tickets, for the production of school and college identity cards as well as for the production of national ID cards. The choice of print technology has a great effect on the cost of the printer and cost of operation, speed, quality and permanence of documents, and noise. Some printer technologies do not work with certain types of physical media, such as carbon paper or transparencies . A second aspect of printer technology that

3456-530: The province of high-end print shops, dye-sublimation printers are now increasingly used as dedicated consumer photo printers. Thermal printers work by selectively heating regions of special heat-sensitive paper. Monochrome thermal printers are used in cash registers, ATMs , gasoline dispensers and some older inexpensive fax machines. Colors can be achieved with special papers and different temperatures and heating rates for different colors; these colored sheets are not required in black-and-white output. One example

3520-526: The ribbons as needed. Color graphics are generally printed in four passes at standard resolution, thus slowing down printing considerably. As a result, color graphics can take up to four times longer to print than standard monochrome graphics, or up to 8-16 times as long at high resolution mode. Dot matrix printers are still commonly used in low-cost, low-quality applications such as cash registers , or in demanding, very high volume applications like invoice printing. Impact printing, unlike laser printing, allows

3584-419: The same advantages as a laser printer in terms of flexibility, but produced somewhat lower-quality output (depending on the paper) from much less-expensive mechanisms. Inkjet systems rapidly displaced dot-matrix and daisy-wheel printers from the market. By the 2000s, high-quality printers of this sort had fallen under the $ 100 price point and became commonplace. The rapid improvement of internet email through

3648-399: The security issues seen when PAP is used with PPP. When the client sends a clear-text password, the authentication server will receive it, and compare it to a "known good" password. Since the authentication server has received the password in clear-text, the format of the stored password can be chosen to be secure "at rest". If an attacker were to steal the entire database of passwords, it

3712-468: The transport layer is expected to be physically secure, such as a home DSL link. Where the transport layer is not physically secure a system such as Transport Layer Security (TLS) or Internet Protocol Security (IPsec) is used instead. PAP is also used to describe password authentication in other protocols such as RADIUS and Diameter . However, those protocols provide for transport or network layer security, and therefore that usage of PAP does not have

3776-410: The wax tends to repel inks from pens , and are difficult to feed through automatic document feeders , but these traits have been significantly reduced in later models. This type of thermal transfer printer is only available from one manufacturer, Xerox , manufactured as part of their Xerox Phaser office printer line. Previously, solid ink printers were manufactured by Tektronix , but Tektronix sold

3840-629: Was a red stamp-pad ink manufactured by Phillips Process Company of Rochester, NY under the name Clear Print. This patent (US3060429) led to the Teletype Inktronic Printer product delivered to customers in late 1966. The first compact, lightweight digital printer was the EP-101 , invented by Japanese company Epson and released in 1968, according to Epson. The first commercial printers generally used mechanisms from electric typewriters and Teletype machines. The demand for higher speed led to

3904-603: Was as clear and crisp as a typewriter. The fastest letter-quality printers printed at 30 characters per second. The term dot matrix printer is used for impact printers that use a matrix of small pins to transfer ink to the page. The advantage of dot matrix over other impact printers is that they can produce graphical images in addition to text; however the text is generally of poorer quality than impact printers that use letterforms ( type ). Dot-matrix printers can be broadly divided into two major classes: Dot matrix printers can either be character -based or line-based (that is,

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3968-427: Was much less noticeable to human vision than vertical misalignment, where characters seemed to bounce up and down in the line, so they were considered as higher quality print. Line printers are the fastest of all impact printers and are used for bulk printing in large computer centres. A line printer can print at 1100 lines per minute or faster, frequently printing pages more rapidly than many current laser printers. On

4032-498: Was sometimes called a network operating system. Examples of such add-on software include Phil Karn's KA9Q NOS (adding Internet support to CP/M and MS-DOS), PC/TCP Packet Drivers (adding Ethernet and Internet support to MS-DOS), and LANtastic (for MS-DOS, Microsoft Windows and OS/2 ), and Windows for Workgroups (adding NetBIOS to Windows). Examples of early operating systems with peer-to-peer networking capabilities built-in include MacOS (using AppleTalk and LocalTalk ), and

4096-424: Was started by retired Howtek employee, Richard Helinski whose 3D patents US4721635 and then US5136515 was licensed to Sanders Prototype, Inc., later named Solidscape, Inc. Acquisition and operating costs are similar to laser printers . Drawbacks of the technology include high energy consumption and long warm-up times from a cold state. Also, some users complain that the resulting prints are difficult to write on, as

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