- Authentication failed: Wrong password
- Comm Error, Connection Error: Fax line error problem
- Data read/check USB: Time expired,; try again
- Data write/ check USB: Inadequate memory
- Door open: Front or rear cover open.
- Enter again: Keystroke error
- File access denied: Change server settings
- File Name exist: Change file name
- File name over limit: Delete some files
- Fuser open
- Incompatible: Problem with machine you are communicating with.
- Low heat error: Off and On or fuser problem
- LSU motor: Laser polygon motor problem
- Compact format
- Updateable code
- Variable weight (light to bold, and anything in between)
- High-quality, scaleable output
- The ability to optimize the rendered characters for various output devices
- The ability to deploy one unified, stroke-based font in all of a developer’s products
LAN stands for local area network. It is a group of two or more workstaions that share a common communication line within a small defined area. LANs are typically used in the home, office or on one or more floors of a building. They have the flexibility to connect as few as two or in some cases thousands of workstations. LANs are extremely popular because of their wide applications for business and personal use. By joining workstations together, users have shared access to each other’s files or hardware such as printers or CD drives. There are many different approaches to setting up a LAN. The principal types you are likely to encounter are described in this chapter under the headings Topologies and Protocols. LANs can also be linked together
by various means to enable communication between different groups in an organisation.
Ethernet is standardized as IEEE 802.3. The combination of the twisted pair versions of Ethernet for connecting end systems to the network, along with the fiber optic versions for site backbones, is the most widespread wired LAN technology. It has been in use from around 1980 to the present, largely replacing competing LAN standards such as token ring, FDDI, and ARCNET.
Carrier Sense and Multiple Access
In a traditional, or hub-based, Ethernet environment, only one NIC can successfully send a frame at a time. All NICs, however, can simultaneously listen to information on the wire. Before an Ethernet NIC puts a frame on the wire, it will first sense the wire to ensure that no other frame is currently on the wire. If the cable uses copper, the NIC can detect this by examining the voltage levels on the wire. If the cable is fiber, the NIC can detect this by examining the light frequencies on the wire. The NIC must go through this sensing process, since the Ethernet medium supports multiple access—another NIC might already have a frame on the wire. If the NIC doesn’t sense a frame on the wire, it will transmit its own frame; otherwise, if a frame is found on the wire, the NIC will wait for the completion of the transmission of the frame and then transmit its own frame.
If two or more devices simultaneously sense the wire and see no frame, and each places its frame on the wire, a collision will occur. In this situation, the voltage levels on a copper wire or the light frequencies on a piece of fiber get messed up. For example, if two NICs attempt to put the same voltage on an electrical piece of wire, the voltage level will be different from that of only one device. Basically, the two original frames become unintelligible (or indecipherable). The NICs, when they place a frame on the wire, examine the status of the wire to ensure that a collision does not occur: this is the collision detection mechanism of CSMA/CD.
If the NICs see a collision for their transmitted frames, they have to resend the frames. In this instance, each NIC that was transmitting a frame when a collision occurred creates a special signal, called a jam signal, on the wire. It then waits a small random time period, and senses the wire again. If no frame is currently on the wire, the NIC will then retransmit its original frame. The time period that the NIC waits is measured in microseconds, a delay that can’t be detected by a human. Likewise, the time period the NICs wait is random to help ensure a collision won’t occur again when these NICs retransmit their frames.
Collision detected procedure
- Continue transmission until minimum packet time is reached (jam signal) to ensure that all receivers detect the collision.
- Increment retransmission counter.
- Was the maximum number of transmission attempts reached? If so, abort transmission.
- Calculate and wait random backoff period based on number of collision
- Re-enter main procedure at stage 1.
n 1985, the first DTP program PageMaker came on the market, combined with the first affordable and low-priced Postscript printer. This first version was for Apple computers with their operating systems Mac OS only. Just some years later, a Windows version followed. The developer and manufacturer was Aldus. Meanwhile, it is part of Adobe’s product range. The current version 7.0 is made for business, small-office/ home office (SOHO) and education users to produce professional documents for printing and electronic distributing, like:
• basic brochures
The target groups of this software are business people and educators with little or no design experience. It integrates other Adobe software like Photoshop, Illustrator and Acrobat with import filters. The output formats are:
• Adobe PDF
• prepress files
In order to create documents in a short time, the software package includes additions like:
• Templates for, among others, newsletters, brochures, visiting cards and flyers
• 150 PostScript fonts
• 4700 stock illustrations
• 300 stock photographs
• Acrobat Distiller 5.0 software to create PDF files
The big advantage of PageMaker is its clear comprehensibility which leads to a fast understanding of the handling.
The big disadvantages are:
• only one undo command is possible
• no spreadsheet support
• the Import of Adobe PDF is only possible as a graphic
• the Spell-Checker works in the text mode window only
• generating of bad HTML source code
The Hewlett Packard Graphics Language (HP GL) is widely used by pen plotters used to produce engineering drawings. HP GL has been widely emulated by other plotter manufacturers, and is the de facto standard language for pen plotters. A pen plotter is a slow device, a complex drawing can easily take have an hour to plot, and plotters are often noisy and difficult to set up. For these reasons many laser printers offer an HP GL emulation, normally copying the HP7475A desktop plotter, which can be used for draft prints of drawings.
As most laser printers do not print in color, and cannot print on the very large paper sizes used by plotters, they are normally only used for draft prints, but in a few situations, such as printed circuit board designs, laser printers are used in preference to plotters. HP GL version 2 has been incorporated into the PCL 5 language to provide PCL with vector graphics capabilities. HPGL uses two-letter mnemonics as instructions for drawing lines, circles, text, and simple symbols. HPGL has evolved over the years as HP added features to its line of pen, electrostatic, inkjet, and laser plotters and printers.
There is one primary drawback to HPGL: it is bulkier than other plotting languages, which means it takes longer to transmit an HPGL plot file. To overcome the limitation, Hewlett-Packard in 1988 introduced HPGL/2, which featured "polyline encoding," a form of data compression that reduces the plot file size and, hence, transmission time by two-thirds.
The original HP/GL-Language does not support definition of line width, as this parameter was determined by the pens loaded into the plotter. With the advent of the first inkjet plotters, line width for the "pens" specified within the HP/GL-files had to be set at the printer so it would know what line width to print for each pen, a cumbersome and error-prone process. With HP/GL-2, definition of line width was introduced into the language and allowed for elimination of this step. Also, among other improvements a binary format was defined that allowed for smaller files and shorter file transfer times, and the minimal resolution was reduced.
In TCP/IP networks, the MAC address of a subnet interface can be queried with the IP address using the Address Resolution Protocol (ARP) for Internet Protocol Version 4 (IPv4) or the Neighbor Discovery Protocol (NDP) for IPv6. On broadcast networks, such as Ethernet, the MAC address uniquely identifies each node and allows frames to be marked for specific hosts. It thus forms the basis of most of the Link layer (OSI Layer 2) networking upon which upper layer protocols rely to produce complex, functioning networks.
Different kinds of Printer Inks.
Printer inks come in different kinds.
First is the original equipment manufacturer (OEM) ink. This type is designed to work with specific printer models. It provides the best quality print and usually comes with a warranty. This is the most expensive yet reliable type of ink.
Compatible Printer Inks
Since most users prefer cheaper printer inks, they have resorted to buying compatible printer inks instead. They are designed to comply with OEM printing standards. Like OEM inks, they are designed only for specific printer brands.
Finally, remanufactured printer inks are made from recycled ink. They are the cheapest kind of ink but can be unreliable.
What should you choose?
When buying a printer ink, it is always best to check for your printer's compatibility. Different printer models work with specific printer inks. Make sure you buy only the right ink for your printer else you can damage it and void the warranty on your printer.
Do not be easily fooled by companies claiming to sell the “best” printer inks. Check for the packaging. Make sure it is not tampered and that you buy only from a reputable dealer.
If you are looking for inks that provide high quality prints, it is always best to buy an OEM ink. It is expensive but it provides lasting and better results than other types.
Buying printer cartridges online will save you a lot of money. There are several online dealers of printer ink and cartridges. These online dealers offer discounts on purchases. Buying online gives you the option of doing your research on the various suppliers and choosing the best discount price. These suppliers will deliver printer cartridges free of cost right at your doorstep, saving you money on traveling and shipping.
To isolate whether the issue is with printer’s Hardware or Software let’s print a Test page from the printer by disconnecting the printer’s USB cable from the Computer or from the printer side.
Now, the results show two scenarios:
One is Hardware issue(If the self test is not printed from printer).
Second one is Software issue(If the self test is printed from printer).
If the printer does not print a Self Test page from the printer, it confirms that the printer hardware is not functioning properly.Educate the Customer by stating that I’m sorry to say this. As per the results, I suspect that the printer hardware is not functioning properly. However, let us try some more troubleshooting steps to isolate and fix the issue.
Step 1: Connect the printer directly to wall out let.
Step 2: Check the ink level.
Step 3: Cleaning of cartridge and printer contacts.
Step 4: Perform a Power cycle steps to remove static electricity from printer.
Follow the steps to Power cycle the printer :
1.Unplug the power supply from the wall outlet.
2.Unplug the power supply from the back of the printer.
3.Wait at least 20 seconds, and then plug in the supply back into the wall outlet.
4.Plug in the power supply back into the printer.
5.Press the power button to turn the printer on.
After performing all the steps, try printing a Self-Test page from printer.
A control code is a character that initiates a printer function, for example
Carriage Return (CR), Line Feed (LF), Form Feed (FF), etc.
Carriage Return (CR)
A carriage return is a special code that moves the cursor (or print head) to the beginning of the current line. In the ASCII character set, a carriage return has a decimal value of 13 (0D Hex).
Line Feed (LF)
A line feed is a code that moves the cursor on a display screen down one line. In the ASCII character set, a line feed has a decimal value of 10 (0A Hex).
On printers, a line feed advances the paper one line.
Form Feed (FF)
Printers that use continuous paper normally have a form feed button or command that advances the paper to the beginning of the next page.
A special character that causes the printer to advance one page length or to the top of the next page. In systems that use the ASCII character set, a form feed has a decimal value of 12 (0C Hex).
Usually, artwork files prepared on a computer, are used to produce a printing plate. The plate
is fitted to an offset printing press. Ink is applied to the image on the plate and, as the press
rotates, the ink offsets to a rubber blanket on another cylinder. The ink is again offset from the
blanket to paper or other material.
The most common kind of offset printing is derived from the photo offset process, which involves using light-sensitive chemicals and photographic techniques to transfer images and type from original materials to printing plates. In current use, original materials may be an actual photographic print and typeset text. However, it is more common — with the prevalence of computers and digital images — that the source material exists only as data in a digital publishing system. Offset litho printing on to a web (reel) of paper is commonly used for printing of newspapers and magazines for high speed production. it cant print variable repeat in one machine.
Offset printing holds about 70% of the printing market. Other printing processes include:
gravure, letterpress, flexographic, intaglio, and silk screening.
Dots per inch (DPI) is a measure of spatial printing or video dot density, in particular the number of individual dots that can be placed within the span of one linear inch (2.54 cm.) The DPI value tends to correlate with image resolution, but is related only indirectly.
DPI is a physical characteristic of a printer. Every printer prints dots that when put next to each other comprise a photo. Each dot has a physical size. DPI is also known as the maximum resolution that a printer is capable of. Low-end printers have lower DPI while high-end printers have higher DPI.
The range of DPI supported by a printer is most dependent on the print head technology it uses. A dot matrix printer, for example, applies ink via tiny rods striking an ink ribbon, and has a relatively low resolution, typically in the range of 60 to 90 DPI. An inkjet printer sprays ink through tiny nozzles, and is typically capable of 300-600 DPI. A laser printer applies toner through a controlled electrostatic charge, and may be in the range of 600 to 1800 DP.
if a printer supports 1200 DPI it means that the printer can print 1200 dots per inch (on both X or Y axis). When printing it is important to make sure that the DPI is higher or equal to the number of pixels per inch in the source photo. If the DPI is lower the printer will not be able to fully display the high resolution photo. When the DPI is higher the printer will use multiple dots to represent one photo pixel. DPI is not relative to the page size. DPI is a fixed number for a given printer.
Kyocera has its own manufacturer specific language. Kyocera uses Kyocera Prescribe in addition to HP PCL emulation. Prescribe is a good language for true type fonts. Mostly it is being used for minicomputer applications and applications using barcodes.
IBM IPDS (Intelligent Printer Data Stream) has more features for IBM mainframe. IBM introduced "Advanced FunctionPrinting" (AFP). AFP is a way in which complex documents can bedescribed on IBM mainframes and minicomputers, and is converted intothe IPDS print language by the operating system on the computer. IPDS does not support other manufacturer's drivers. User must have an IPDS comatible print to print a document. But some printer manufacturers provide IPDS emulation to make PCL or Postscript available to IBM systems. User has to use an external computer to use these emulations which translates IPDS commands into PCL or Postscript.
A wide range of related software tools exist in this field, including many plug-ins and tools related to the applications listed below.
# Adobe InDesign
# Adobe PageMaker, was Aldus Pagemaker
# Adobe Home Publisher, was Aldus Personal Press, was Silicon Beach Personal Press
# Advanced Print Publisher, formerly the 3B2 Publishing System
# FrameMaker, now owned by Adobe
# iCalamus for Mac OS X
# Impression Publisher – RISC OS
# MemoryPress – DTP that allows online collaboration
# Microsoft Publisher
# Microsoft Word 2008 – This Word release contains a DTP mode
# OvationPro – RISC OS
# PagePlus SE (External link: http://www.freeserifsoftware.com/software/PagePlus/)
# PageStream, formerly known as Publishing Partner
# Prince XML, by YesLogic
# Print Explosion, by Nova Development
# Print Shop, originally produced by Broderbund
# Ventura Publisher, now owned by Corel and originally developed by Ventura Software
# UltraXML, XML Dynamic Publishing Solution
# Print MIS (http://www.printmis.com), Solution provider for the printing industry
# Business Builder for Print (http://www.systems4print.co.uk
AIO for home users usually is not networked and connected with USB or parallel.
If you're planning to use it as a photocopier, it's going to cost you considerably more than having copies made at your local print shop. They're great for convenience when you need a quick copy, but you wouldn't want to do any kind of volume on them.
Another thing to consider is the quality of the various components. For example, the scanner may not be as high resolution as some stand-alone models. If you're planning to scan old photographs or negatives and want the highest possible resolution, you probably won't get quite as good a result from a multifunction printer/scanner as you would from a dedicated scanner. The quality of the image depends on DPI or dots per inch. The standard (600x600) will suffice for printing but is unsuitable as regards quality of photo. Scanner resolutions must be noticed, as these are usually low in multifunction models. There is a wide gap as regards quality between interpolated and optimal resolution.
The same goes for the printing capabilities. You can get standalone printers that will print at higher resolutions or on larger paper than most multifunction units.
The final thing to consider is that if your printer breaks down it will affect your fax, scanner and copier too. This may cause problems if your office needs these machines to do business. Also, by using your printer for multiple functions you will go through a lot of ink cartridges and toner. The cost of using these forms of ink is much higher for making copies than using a regular copy machine.
Having separate units means you would only be without one of them if you ever need repairs done. If your needs are relatively basic, however, a multifunction is a great choice. You can get all the same functions as having 3 or 4 separate machines, for less money and in a lot less space.
The host sends a reply corresponding to the message sent by the port scanner. This kind of reply indicates that the port is open and a service is running on the host and can be accessed.
The host sends an error message or a corresponding reply that indicates a closed
The host sends no reply at all. Usually, this indicates that the port is somehow blocked or filtered. Open ports present the highest risks as they offer potential attackers the opportunity to attack the services and applications associated with open ports as well as the operating system of the host. There are different types of port scans associated with particular protocols and particular messages which are part of a protocol. For example, the TCP SYN scan method makes use of the SYN message. Normally, this message is sent as part of the initial handshake, if another host wants to establish a connection. The TCP SYN scan method consists of the following steps:
1. The port scanner sends a SYN message to a port of the host.
2. If the port is closed, the host sends an RST message.
If the port is open, the host sends a SYN/ACK message. If the port is filtered, the host sends no reply at all.
3. When the port scanner receives the SYN/ACK message, it replies by sending an RST message. This message breaks off the handshake.
From the attacker’s point of view, the advantage of this method is that actually no connection is established as the port scan is carried out on the handshake level. Accordingly, there will be no entry in the log of the corresponding service. Though, many firewalls are able to detect this kind of s port scan.
In the third of this article series on how to set up a technical document template by using Microsoft Word we'll explain the various printing options you can choose from to print your MS Word technical document.
While your document template is open, select File > Page Setup to display the Page Setup dialog box.
Click and select the PAPER tab.
Click PRINT OPTIONS button to display the PRINT tab and the print options available. This is the same dialog box that you can also reach by selecting File > Print and then selecting the Options button from the main menu.
DRAFT OUTPUT option, when selected, will print a fast and low-quality draft copy with no images. The blocks where the images are located will appear as blank spots.
I recommend you select the UPDATE FIELDS and UPDATE LINKS options to make sure you have the latest values for the date and time fields as well as the most current document links before your document is printed.
BACKGROUND PRINTING option, selected by default, allows you to continue working while a long document is sent to printer and printed on the "background."
PRINT POSTSCRIPT OVER TEXT option, when selected, prints any PostScript-coded document components (like the watermark, for example) on top of the body text, instead of underneath it.
REVERSE PRINT ORDER option, when selected, reverses the print order of the pages; prints the last page first and the first page last.
XML TAGS option, when selected, prints all the XML tags in your document, whether they are normally visible or not.
BACKGROUND COLORS and IMAGES option, when selected, prints any background images or colors (like in a watermark) underneath the body next.
FIELD CODES and HIDDEN TEXT options, when selected, print any field codes and hidden texts that you might not want printed normally. NOTE: If you do not select it, the CONTENT of the field code will still print without, however, printing the field code itself.
DOCUMENT PROPERTIES option, when selected, prints ( as a new section at the end of the Word document) all the information you have entered into the DOCUMENT PROPERTIES dialog box by selecting File > Properties from the main menu.
NOTE: If you enter more than one Comments field through selecting Insert > Field from the main menu, all comments will print in the main body of the document but only the LAST comment will be printed in the Document Properties block.
Click OK when you're done with the printing options to return to the PAPER tab.
Click OK once again to close the Page Setup dialog box.
How can I assign IP addresses properly?
The Internet Protocol address is a unique number that represents a specific computer in a network. Format of the IP Address is four numbers separated by dots, e.g. '192.168.110.171.' Each number should be decimal of 0 through 255.
The IP address is compiled from 'network ID + user ID.' This results in three different IP address 'classes.' Representing the network ID as 'n' and the user ID as 'u,' each class has the following attributes:
Class IP Addressing First Segment Range Application Number of Networks Number of Users A n.u.u.u 0 <127 Large scale network 126 16,777,214 B n.n.u.u 128 <191 Mid scale network 16,384 65,634 C n.n.n.u 192 <223 Small network 2,097,150 254
For example, in a class C network, you can assign an IP address as '192.168.40.1.'
Devices having IP addresses with different network IDs ('n' above) cannot communicate even when they are in the same network segment.
Following is an example of a Class C IP network with 3 computers and 1 IB-21E/IB-22 printer:
Most inkjet printers will print 2 to 6 pages in one minute (ppm). Pages with graphics will take longer and range about 1to 3 minutes. Ink jet printers are able to provide consumers with high quality prints at a very reasonable price. They are much quieter and also produce much higher quality. You can buy an inkjet printer that will produce photo quality picture prints, something that would have been impossible with a dot matrix.Inkjet printers are considerably cheaper to buy. High end printers are capable of producing good quality images when used with special paper. Most models are relatively light weight and compact so they don't take up too much space on the desk. Ther are more viable option for photo print quality having a multi-colour output. It is usually 4-colour but there are 6-colour and even 8-colour outputs available. The recently launched Inkjet printers have sizably reduced their cost of cartridges which are now in vogue again. In contrast to additional luxurious technologies like thermal transfer printer, dye-sublimation printers, and laser printers, ink jets have the benefit of approximately no warm-up and a lesser printing cost per page.
One drawback of the ink jet printer is the cost of printer cartridges, which can be quite expensive. The design of the ink cartridges does also mean that they are prone to clogging. As the ink used is water soluble it is also important to avoid even small amounts of water coming into contact with your finished document, as this will easily cause smudging. Another disadvantage is the possibility of an affect called bleeding. This is when the ink is carried side ways and results in a smudged document. It means the ink is carried to a side away from the preferred location by the capillary action along the fibre of the paper; the result is a muddy or smudged appearance on some types of paper. Inkjets produce goods quality print on black text but are very slow in their performance. Also the prints emerge from the printer slightly wet and may need time to dry. Inkjets aren't designed for high volume printing. Due to the cost of ink, running an inkjet printer over time is a more expensive than a laser printer.
Third-party ink suppliers sell ink cartridges at significantly reduced costs (often 10%−30% of OEM cartridge prices) and also sell kits to refill cartridges, and bulk ink, at even lower prices.
Many vendors' "intelligent" ink cartridges have been reverse-engineered. It is now possible to buy inexpensive devices to reliably reset such cartridges to report themselves as full, so that they may be refilled many times.
Print lifetime is highly dependent on the quality and formulation of the ink, as well as the paper chosen. The earliest inkjet printers, intended for home and small office applications, used dye-based inks. Even the best dye-based inks are not as durable as pigment-based inks, which are now available for many inkjet printers.
Adobe does not sell printers but it sells Postscript license to the manufacturers. Before Postscript Level 2, the license fees charged by Adobe were high, so some manufacturers tried to emulate the PostScript language. But nowadays license fees has been reduced and manufacturers prefer to use Postscript instead of emulated languages.
The SSH protocol addresses each of the basic security concepts. SSH uses public-key cryptography to authenticate the remote computer and allow the remote computer to authenticate the user, if necessary. Note that SSH is a protocol that can be used for many applications. Some of the applications may require features that are only available or compatible with specific SSH clients or servers. For example, using the SSH protocol to implement a VPN is possible, but presently only with the OpenSSH server and client implementation.
Confidentiality: Each SSH connection is encrypted, preventing an eavesdropper from viewing information. For added security, SSH periodically reexchanges keys to ensure that a compromise of one set of keys does not compromise the entire session. In contrast, CTCP, IPsec, and IPv6 only exchange keys at the beginning of the connection.
Authentication: Before establishing a connection, the client must authenticate the server and the server must authenticate the client. Client authentication can be any combination of certificates (keys), passwords, or digital tokens. Although SSH is usually used with one-part authentication (a password or a key), it can support two- and three-part authentication systems. The server only uses a certificate to authenticate with the client.
Authorization: SSH limits the traffic that can enter the tunnel and can restrict how data exits the tunnel. For remote login access, SSH restricts authorization to the user’s login privileges.
Integrity: SSH uses encryption and cryptographic checksums to validate each packet. Any packet that fails an integrity check is viewed as an attack, which terminates the connection.
Nonrepudiation: Each packet is cryptographically signed using an HMAC, ensuring that the data actually came from the sender. SSH has three primary uses: establish a secure network tunnel, provide a VPN with port-forwarding characteristics, and supply application-layer login functionality.
An outline font technology developed jointly by Microsoft and Apple. Because TrueType support is built into all Windows and Macintosh operating systems, anyone using these operating systems can create documents using TrueType fonts.
Since being introduced in 1991, TrueType has quickly become the dominant font technology for everyday use, and is even displacing PostScript in many publishing environments.
PostScript is an object-oriented language, meaning that it treats images, including fonts, as collections of geometrical objects rather than as bit maps. PostScript fonts are called outline fonts because the outline of each character is defined. They are also called scalable fonts because their size can be changed with PostScript commands. Given a single typeface definition, a PostScript printer can produce a multitude of fonts. In contrast, many non-PostScript printers represent fonts with bit maps. To print a bit-mapped typeface with different sizes, these printers require a complete set of bit maps for each size.
The principal advantage of object-oriented (vector) graphics over bit-mapped graphics is that object-oriented images take advantage of high-resolution output devices whereas bit-mapped images do not. A PostScript drawing looks much better when printed on a 600-dpi printer than on a 300-dpi printer. A bit-mapped image looks the same on both printers.
Every PostScript printer contains a built-in interpreter that executes PostScript instructions. If your laser printer does not come with PostScript support, you may be able to purchase a DIMM that contains PostScript.
communications between computers all over the world, and access to data and applications at geographically scattered sites (including the World Wide Web)
* Intranets, which make information readily visible via a browser to users of a LAN or WAN, such as within a single corporation
* Extranets, which share data between users within a group of companies, for example a supplier may create an Extranet with its major customers to facilitate sharing of information
* Private networks: LANs and WANs where data is shared and e-mails are exchanged between members of a single organisation
* Virtual Private Networks (VPNs) where remote users can be given access rights to make a dial-in connection via modem to the resources of a private network (usually protected by encryption).
The wide use of TCP/IP means that you will need to understand the essentials of this group of protocols when installing and
maintaining networked machines.
Media Select (Alphanumeric ID Command)
Format: ESC & n # W 100[string]
Hex: 1B 26 6E # 57 64[string] (# is specified in the text below)
Function: Assigns an ID string to the media type.
Description: Media selection is one function of the Alphanumeric ID Commands. By setting operation = 100, it is possible to assign string IDs to media types.
Render Algorithm Command
Format: ESC * t # J
Hex: 1B 2A 74 # 4A (# is specified in the text below)
Function: Sets the Render Algorithm.
Description: The value of # can be in the range 0 - 12. Any other value causes the command to be ignored.
Driver Configuration Command
Format: ESC * o # W [device_id function_index Arguments]
Hex: 1B 2A 6F # 57 (# is specified in the text below)
Function: Specifies Lightness, Saturation, Scaling Algorithm, Select/Download Color Map, Trapping Mode, and Total amount toner control.
Description: The value of # is fixed to 3. (The number of bytes of device_id + function_index + Arguments)
Description: The value of # is fixed to 3. (The number of bytes of device_id + function_index + Arguments)
Production Printing enables organizations to automate the reproduction of mass quantities of an original document. The production printing processes may be categorized into two broad groups: traditional plate printing and non-traditional plateless printing. The traditional image carrier processes produce numerous reproductions of an original subject by means of a printing press, which holds an inked image carrier and applies the pressure necessary to transfer the image to a substrate. Traditional processes include such methods as letterpress. Lithography, flexography, screen printing and gravure. The non-traditional printing processes do not use traditional image carriers or presses and include photography and non-contact processes like electro photography, thermal imaging, and ink jet printing. They use digital imaging and copier-like printers that produce an image during each cycle The non-traditional printing speed is much slower than traditional plate printing processing in that a large amount of computer memory is needed for repeating or changing information during each cycle. There is no make ready and no drying time, but the overall costs are slightly higher than the traditional printing. The non-traditional printing process is used for mainly short runs, on-demand or variable information printing.
The main components of ink are:
It is the carrier for the colorant and keeps the ink in a liquid state. It can be water, oil, or other solvent.
It is the substance that gives color to the ink. It can be a dye or a pigment. Ink that uses dye as the colorant is called dye-based ink. Ink that uses pigment as the colorant is called pigment-based ink.
It is a chemical that fully dissolves in the chemical base. Generally dye-based ink has a brighter color than pigment-based ink, but because the dyes are dissolved in the chemical base, they tend to soak into the paper, which makes the ink less efficient and causing the ink to bleed into the paper.
Pigment-based ink (Gel)
A pigment does not dissolve in the chemical base. Pigment is a very fine powder of solid colorant particles, dispersed throughout the chemical base. The pigment particles do not soak into the paper together with the chemical base, they remain on or between the fibers on the surface of the paper. Because pigment particles are larger than dye particles, pigment-based ink is more durable and ultraviolet resistant. Also the pigment particles can be coated to enhance the properties of the ink.
Hp PCL or Hewlett Packard Printer Command Language was introduced by the Hewlett-Packard. It is independent of host system, device drivers, I/O interface, and network communications. Its purpose is to bring all HP printers together under a common control structure. HP used it in its first desktop laser printer. PCL is an Escape Code language. HP has been using this language for its dot-matrix and inkjet printers before the invention of laser printers. PCL commands are compact escape sequence codes that are embedded in the print job before being sent to the printer. PCL fonts quickly translate application output into high quality raster print images. PCL has several versions available.
PCL 1 was introduced in 1980. It is simple language having capabilities for basic printing. PCL 1 prints nothing but only text. Supported by all HP LaserJet series printers (except the HP LaserJet 3100 and 3150 series products).
PCL 2 added Electronic Data Processing/Transaction functionality. Supported by all HP LaserJet series printers (except the HP LaserJet 3100 and 3150 series products).
PCL 3 was introduced in 1984 with the original HP LaserJet. Released with the following printers:
HP LaserJet series printer,
HP LaserJet Plus series printer.
It provided the commands and features required for simple high quality word processing and data printing. Allowed for the use of a limited number of bitmapped fonts and graphics.
PCL 3 provided simple word processing and data sharing. It supported not only small bitmap fonts but also small bitmap graphic printing. Many other manufacturers emulate PCL 3 referred to as LaserJet Plus emulation. PCL 3 is still in use on several impact printers which replaced the obsoleted HP models. It does not support downloadable or scalable fonts. It is pixel based printer language that primarily describes images by pixel.
Released with the following printers: HP LaserJet Series II, HP LaserJet IID, HP LaserJet IIP, and HP LaserJet IIP Plus series printers.
Provided new page printing capabilities. Supported macros, larger bitmapped fonts and graphics. Introduced in 1985.
The LaserJet Plus printer was superseded by the LaserJet series II, also an 8 p.p.m. printer. The LaserJet II series of printers included the LaserJet IIP, a 4 p.p.m. personal printer, and the LaserJet IID, a duplex version of the LaserJet II. The LaserJet II introduced the PCL 4 language, which built upon PCL 3 by adding the ability to use more, larger bitmap fonts, and more bitmap graphics. The standard LaserJet II could manage just over half a page of bitmap graphics, but with the addition of some extra memory this could be expanded to a whole page.
PCL 4 was introduced on the HP LaserJet II in 1985, adding macros, larger bitmapped fonts and graphics. PCL 4 is still popular for many applications.
PCL 4 was backwards compatible with PCL 3 (PCL 3 jobs would print perfectly well under PCL 4), but the additional features took it well beyond the bounds of word-processing, and allowed it to be used for charts, graphics and simple desktop publishing. PCL 4 has been superseded for office printers, but is still commonly used in personal printers as it requires relatively little processing power in comparison with later versions of the PCL language. The version of PCL 4 used on the LaserJet IIP was a slightly enhanced over the version used on the standard LaserJet, and provided a compression method for bitmap graphics to reduce the amount of data which the computer had to send to the printer.
There is some overlap between desktop publishing and what is known as Hypermedia publishing (i.e. Web design, Kiosk, CD-ROM). Many graphical HTML editors such as Microsoft FrontPage and Adobe Dreamweaver use a layout engine similar to a DTP program. However, some Web designers still prefer to write HTML without the assistance of a WYSIWYG editor and resort to such software, if at all, solely for complex layout that cannot easily be rendered in hand-written HTML code.
There are several different DTP applications to produce professional layouts. They are distinguished by their different functions and manufacturers. Some of them are even from the same manufacturer like the Adobe products PageMaker, Indesign and Framemaker. In
this module, it is impossible to describe all functions and features for each program. For detailed information, visit their web pages. We can only give an overall view relating to their biggest differences. The most popular DTP applications are:
• Adobe PageMaker
• Adobe InDesign
• Adobe FrameMaker
WPA2 is the IEEE 802.11i implementation from the Wi-Fi Alliance. Instead of using WEP, which uses the weak RC4 encryption algorithm, the much more secure Advanced Encryption Standard (AES)–counter mode CBC-MAC Protocol (CCMP) algorithm is used. WPA2 implements the mandatory elements of 802.11i. In particular, it introduces a new AES-based algorithm, CCMP, which is considered fully secure. Certification began in September, 2004; from March 13, 2006, WPA2 certification is mandatory for all new devices to bear the Wi-Fi trademark. AES is used for encryption with a 128-bit key. AES-CCMP incorporates two cryptographic techniques—counter mode and CBC-MAC—and adapts them to wireless frames to provide a robust security protocol between the client and AP. Most newer Wi-Fi CERTIFIED devices support the security protocols discussed above, out-of-the-box, as compliance with this protocol has been required for a Wi-Fi certification since September 2003.
There are two varieties of EAP: one for wireless and one for LAN connections, commonly called EAP over LAN (EAPoL).
One of the concerns in wireless is allowing a WLAN client to communicate to devices behind an AP. Three standards define this process: EAP, 802.1x, and Remote Authentication Dial In User Service (RADIUS). EAP defines a standard way of encapsulating authentication information, such as a username and password or a digital certificate that the AP can use to authenticate the user. EAP is not a wire protocol; instead it only defines message formats. Each protocol that uses EAP defines a way to encapsulate EAP messages within that protocol's messages. In the case of 802.1X, this encapsulation is called EAPOL, "EAP over LANs". EAP is basically an extension of the Point-to-Point Protocol (PPP) and one of the first forms of EAP was EAP-MD5, which used Challenge Handshake Authentication Protocol (CHAP) for authentication. When EAP is invoked by an 802.1X enabled NAS (Network Access Server) device such as an 802.11 a/b/g Wireless Access Point, modern EAP methods can provide a secure authentication mechanism and negotiate a secure PMK (Pair-wise Master Key) between the client and NAS. The PMK can then be used for the wireless encryption session which uses TKIP or CCMP (based on AES) encryption. Here are some of the extensions of EAP:
Supports CHAP with static passwords for authentication. EAP-MD5 differs from other EAP methods in that it only provides authentication of the EAP peer to the EAP server but not mutual authentication. By not providing EAP server authentication, this EAP method is vulnerable to man-in-the-middle attacks
Supports x.509v3 digital certificates for authentication. It was co-developed by Funk Software and Certicom. It is widely supported across platforms, although there is no native OS support for this EAP protocol in Microsoft Windows, it requires the installation of small extra programs such as SecureW2.
(Lightweight EAP) Supports static passwords and allows for per-session WEP keys. It provides mutual authentication and session key establishment between an EAP peer and an EAP server
(Protected EAP) Supports static and one-time passwords (OTP), where SSL secures the connection so that MS-CHAP can be used for authentication and the username and password are encrypted to protect them from an eavesdropping attack (a digital certificate is required only on the server). The PEAP standard was created by Microsoft, Cisco, and RSA after EAP-TTLS had already come on the market. Even with its late start, Microsoft’s and Cisco’s size allowed them to quickly overtake EAP-TTLS in the market. So wide is the marketplace adoption of PEAP that even Funk Software, the inventor and backer of EAP-TTLS, had little choice but to support PEAP in their server and client software for wireless networks.
Supports faster authentication, where a shared secret key is used to encrypt authentication information (similar to PEAP)
PEAPv1/EAP-GTC was created by Cisco as an alternative to PEAPv0/EAP-MSCHAPv2. It allows the use of an inner authentication protocol other than Microsoft's MSCHAPv2. EAP-GTC (Generic Token Card) is defined in RFC 3748. It carries a text challenge from the authentication server, and a reply which is assumed to be generated by a security token. EAP-GTC does not protect the authentication data in any way.
In earlier machines, toner was poured by the user from a bottle into a reservoir in the machine. Modern machines feed directly from a cartridge. Empty cartridges are sometimes refilled by third party vendors. Using toner cartridges against the laser cartridges is beneficiary. The laser printer toners are able to print thousands of pages, and are less expensive per page compared to inkjet cartridges. The printing speed is faster than inkjet cartridges while they almost work on every type of paper. In due course, they prove to be much economical if a lot of printing work is involved. A compatible cartridge benefits you with cost savings and at times massive savings up to 50%. It all depends upon your requirements to utilize these toner cartridges to enhance your printing. Basically there are 2 types of cartridges, originals and non-originals and there are 2 types of non-originals being compatibles and remanufactured (this goes for inks also as does the information below). Otherwise known as non-genuine, after market this is how they work:-
- Compatibles are actually a brand new cartridge manufactured to work in the same way (without breaking the trademark, copy protection laws) as the same original cartridge with the same machines. The benefit you gain from these is obviously cost savings with at times massive savings up to around 50%. The downside is they are not as environmentally friendly as remanufactured toners and there are the occasional failures and complaints about lower quality (though failure rates for the top companies making these are within industry norms and not significantly higher than those of the original manufacturers themselves)
- Remanufactured toners however are a little different as they take an empty original (it should have only been used ONCE) and fill it with toner. As long as you buy from a reputable retailer it will have also been checked to determine if parts need to be replaced as well as toner refilled. You also get good cost savings as you do with compatibles but the environment wins out big time as you helping ‘close the loop’ by reusing an empty original. Once again the same applies as above with quality and failures.
As a fine powder, toner can remain suspended in the air for some period, and is considered to have health effects comparable to inert dust. It can be an irritant to people with respiratory conditions such as asthma or bronchitis. Following studies on bacteria in the 1970s that raised concerns about health effects resulting from pyrol, a contaminant created during manufacture of the carbon black used in black toner, manufacturing processes were changed to eliminate pyrol from the finished product.
According to recent research, some laser printers emit submicrometer particles which have been associated in other environmental studies with respiratory diseases .
Two ways on how to install a printer are shown in the following:
1. a GUI based installation (using the ESP web interface)
2. an installation with command line tools
To show this example, we used the web interface provided by CUPS. It is accessible via Port 631, the standard port for IPP and CUPS.
It is no problem if you have CUPS and other servers on the same machine while using this port.
1. Just type the following URL:
if you are working locally on your server
if you are working on a remote server. .
This procedure will lead you to the starting page of the web interface. Choose "Manage Printers" here to get to the printer overview. This screen shows you all printers installed on your system and their current status. Printers marked green are ready to print, printers marked red with an open tray are stopped. In that case you have to check whether there is a problem
2. In order to install a new one, choose "Add Printer" here.
3. Then you have to give a name to your new printer.
Note: According to the IPP specifications, CUPS is not case sensitive. That means, you do not have to look for the use of capitalization or the use of small initial letters (di351test and DI351TEST specify the same printer!).
Additionally you have the opportunity to give more information about your printer and the location or any other description that might be useful (e.g. any special features or configurations or maybe restrictions)
4. In this step you have to choose the type of connection that you are using for the printer you like to install. Possible settings you can choose are:
• Disk File
• App Socket /HP Jet Direct
• Internet printing protocol
• LPR/LPD Host or printer
• Parallel or serial ports
5. Now you have to put in a valid IP-address and a remote queue name for your printer.
Please see the given examples on the screen for the correct syntax.
6. Now choose your manufacturer. All the manufacturer names offered in this list and the model names offered in the list in Step 7 are generated by CUPS while using the PPD files stored in /usr/share/cups/model/[name of manufacturer] If your printer does not appear in this list, please make sure that there is a PPD file for it in this location. If it is not, get one and just copy it to this location.
7. Now you have to choose a printer. If your printer does not appear in the list you have to install a PPD file on your system.
You need to be logged in as root to do that (or use the “Sper user” command SU).
Now your printer is installed and ready to be configured.
A file virus attacks executable application and system program files, such as those ending in .COM, .EXE, and .DLL. Most of these types of viruses replace some or all of the program code with their own. Only once the file is executed can the virus cause its damage. This includes loading itself into memory and waiting to infect other executables, further propagating its potentially destructive effects throughout a system or network. Examples of file viruses are Jerusalem and Nimda (although Nimda is usually seen as an Internet worm) may also infect common Windows files, as well as files with extensions such as .HTML, .HTM, and .ASP.
A macro is a script of commonly enacted commands that are used to automatically perform operations without a user’s intervention. Macro viruses use the Visual Basic macro scripting language to perform malicious or mischievous functions in data files created with Microsoft Office products, for example. Macro viruses are among the most harmless (but also the most annoying). Since macros are easy to write, macro viruses are among the most common viruses and are frequently found in Microsoft Word and PowerPoint. They affect the file you are working on. For example, you might be unable to save the file even though the Save function is working, or you might be unable to open a new document—you can only open a template. These viruses will not crash your system, but they are annoying. Cap and Cap A are examples of macro viruses.
Boot Sector Viruses
Boot sector viruses get into the master boot record. This is track one, sector one on your hard disk, and no applications are supposed to reside there. The computer at bootup checks this section to find a pointer for the operating system. If you have a multi-operating-system boot between various versions or instances of Windows, for example, this is where the pointers are stored. A boot sector virus will overwrite the boot sector, thereby making it look as if there is no pointer to your operating system. When you power up the computer, you will see a Missing Operating System or Hard Disk Not Found error message. Monkey B, Michelangelo, Stoned, and Stealth Boot are examples of boot sector viruses.