Networking.docx

VR Headset Virtual reality (VR) is being touted as the next frontier in electronic gaming. To experience VR, a user dons a pair of VR goggles or a VR headset, which displays images close to their eyes and blocks out all other light. The images create a 3D world that the user can navigate. VR headset...

VR Headset Virtual reality (VR) is being touted as the next frontier in electronic gaming. To experience VR, a user dons a pair of VR goggles or a VR headset, which displays images close to their eyes and blocks out all other light. The images create a 3D world that the user can navigate. VR headsets got their start in 2012, when the newly formed Oculus company started a Kickstarter project to develop the Oculus VR. Early prototypes showed great promise, and in 2014 Facebook purchased Oculus. The Oculus Rift (shown in Figure 3.38) hit the markets in 2016 and was popular enough that Oculus had product shortages. Today, several companies make VR headsets to compete with Oculus, including Sony, Samsung, Google, and HTC. Figure 3.38 Oculus Rift  By Evan-Amos - Own work, public domain, https://commons.wikimedia.org/w/index.php?curid=62084228 There are two common types of VR headsets—those that connect to a computer or gaming system and those that use a smartphone as the screen. Computer-based headsets have a fairly high hardware requirement, mostly due to the intensive video processing that takes place. For example, the Rift recommends a minimum of an Intel Core i3-6100 or AMD Ryzen 3, FX4350 CPU, 8 GB+ RAM, a GeForce GTX 960, HDMI 1.3, one USB 3.0 port, two USB 2.0 ports, and Windows 10. The Oculus itself has two OLED displays providing 1080 × 1200 resolution per eye at a 90 Hz refresh rate and integrated headphones for 3D audio. It also has embedded sensors that allow for positional and rotational tracking, which can detect the position of a wearer’s head within a millimeter. Nearly all systems also come with a handheld game controller, either a proprietary one or something such as an Xbox One game controller, to allow users to interact with the game. Smartphone-based VR headsets are essentially a head strap with a phone carrier and blinders on the sides to block out light. Users snap their phone into the carrier, which they place on their head. It provides similar effects to an Oculus, but the quality is generally regarded as inferior to PC-based systems. 177 Business applications are being developed for VR as well. For example, store employees could use VR to navigate through shelves to learn the layout of a new store, or engineers could inspect their designs in three dimensions. Other applications, such as medical and other types of hands-on training, are easily within reach. Optical Glasses and Headsets It’s hard to think of any computer product that has generated more controversy in recent years than Google Glass. Some see the glasses-mounted computer as an amazing technological step forward, while others view it as a highly intrusive technology that should be permanently banned. The idea that Google pushed was relatively benign. The company wanted to produce a wearable computer that enhanced the user experience without the user having to think about the device or become distracted by it. Thus, it created a device that basically has the functionality of a smartphone (without the ability to make cellular calls itself) but that was small enough to be worn on an eyeglasses frame. Users see an augmented reality (AR) projected display a few inches from their face that was equivalent to looking at a 25″ screen from about 8 feet away. There’s a touch pad on the side of the device that lets users scroll through menus and make selections. Other inputs can be made by voice command through a microphone or other built-in sensors, such as the accelerometer, gyroscope, magnetometer, proximity sensor, and ambient light sensor. Oh, and it has a camera mounted on it. Yes, it’s the camera that caused the controversy. Figure 3.39 shows Google Glass being worn. Google also produced a version that fits onto prescription glasses frames. Figure 3.39 Google Glass  “Google Glass detail” by Antonio Zugaldia. Licensed under CC BY 3.0 via Wikimedia Commons— https://commons.wikimedia.org/wiki/File:Google_Glass_detail.jpg 178 Table 3.5 outlines some of the technical specifications of the original Google Glass. Table 3.5 Original Google Glass specs Feature Specification Release date To “Glass Explorers” in April 2013 Weight 1.51 oz Operating system Glass OS CPU OMAP 4430 Dual Core RAM 2 GB Storage 16 GB, 12 GB usable Display Prism projector at 640 × 360 pixels, which appears the same as a 25” screen viewed from 8 feet Camera 5MP, 720p HD video Connectivity 802.11b/g, Bluetooth, micro-USB Many complained that the device, with its mounted camera, is an invasion of privacy. In theory, the wearer could take pictures or record video without other people knowing about it. (By default, turning on video recording lights up features on Glass, making it pretty obvious that the wearer is recording. But non-users don’t necessarily know this, and in theory an app could be created to disable the lights.) Indeed, an app was created that allowed wearers to take pictures by just winking. Several establishments in the United States posted signs prohibiting Google Glass from being worn inside, such as restaurants, movie theatres, and casinos. In some countries, the device can be considered illegal spy equipment. Apps could be created to identify faces (imagine walking down the street and seeing a total stranger, but then seeing their name pop up attached to their Facebook profile) or track finger movements to steal passwords or ATM PINs. In addition to privacy concerns, there are safety concerns. For example, wearing Google Glass while driving an automobile could be considered a safety hazard, much like using a smartphone while driving. Another safety concern could be for users, who on occasion have reportedly been accosted for wearing the device. With all of the potential ramifications, many experts in the tech industry wonder if a product like Glass will ever receive mainstream acceptance. On the positive side, Glass and similar products may be more accepted for commercial applications. For example, surgeons have used it on a limited basis during operations. Glass has also been used to help children with autism learn to understand emotions and facial179expressions. Finally, commercial delivery drivers, law enforcement personnel, military personnel, manufacturing supervisors, and journalists can use it to enhance their effectiveness. Google Glass Enterprise Edition 2.0 was released in 2017, intended mostly for business applications. While it upgrades the Wi-Fi to support 802.11a/b/g/n/ac and doubles the storage space to 32 GB, most of the other specifications remain the same as the original. Other companies have created similar wearable smart glasses as well, such as EyeTap, Golden-i, Microsoft HoloLens, Vuzix, and the Epson Moverio. Audio Devices Audio devices, true to their name, produce sound by plugging into a sound card. Many sound cards today are integrated into a device’s motherboard, but some computers still have separate audio expansion cards. Audio devices can provide output, such as through speakers or headphones, or input with a microphone. Speakers and headphones generally connect with a 1/8″ (3.5 mm) audio connector, as shown in Figure 3.40. Audio jacks were shown in Figure 3.26. Most audio connectors will have two thin black bands engraved on them, which separates the connector into three parts: the tip, ring, and sleeve. Because of this, sometimes you will see these connectors referred to as TRS connectors. The tip provides left audio; the first band above the black groove (the ring) provides right audio; and the sleeve is the ground. You’ll notice that the connector in Figure 3.40 has three black bands, providing four connections and making it a TRRS connector. The fourth one is for the microphone. Figure 3.40 1/8″ audio connector Headsets that provide audio and a microphone are popular for audio conferencing calls and video gaming. A sample headset is shown in Figure 3.41. This model connects via USB, as do most headsets. Volume controls and a microphone mute are located on the right earpiece. 180 Figure 3.41 A USB headset Although discussed throughout this chapter, the microphone has yet to be formally defined, a definition that is at once technical and simple. Microphones convert sound waves into varying electrical signals. The result can be recorded, transmitted, or altered in a variety of ways, including amplification. When installing a microphone, you must match its connector with an available one on the computer. Modern choices include the classic analog pink TRS connector and USB. Wireless versions also exist, but their receiver might still be connected to a standard I/O port. Alternatively, the microphone could be paired with a built-in Bluetooth transceiver, headphones, or headset. Configuring a microphone on a PC is most often performed through the Recording tab of the Sound applet in Control Panel. Options include setting the levels and choosing enhancements, such as noise suppression and echo cancellation. Specialized applications may also have internal configuration for the microphone, passing most details of the configuration back to the operating system. 181 Input and Output Devices An input device is one that transfers information from outside the computer system to an internal storage location, such as system RAM, video RAM, flash memory, or disk storage. Without input devices, computers would be unable to change from their default boot-up state. An output device does the opposite of an input device. That is, it takes information that’s stored in RAM or another location and spits it back out somewhere for the user to do something with it. We’ve already covered monitors, which are the most common output device. The other major type of output device is a printer. Further, some devices are capable of managing both input and output.  Frequently, when discussed together, input and output are abbreviated as I/O. The following sections detail different classes of input and output devices, including a hub of sorts that is used for switching between the most common of these devices. We will also demonstrate the similarities shared by these devices as well as their differences. Installation considerations will be presented where appropriate. The following devices are covered in the subsequent sections: Keyboard Mouse Touch pad Signature pad Game controller Barcode or QR scanner Magnetic or chip reader NFC/tap pay device Printer Scanner KVM switch Keyboard The keyboard is easily the most popular input device, so much so that it’s more of a necessity. Very few users would even think of beginning a computing session without a working keyboard. Fewer still would even know how. The U.S. English keyboard places keys in the same orientation as the QWERTY typewriter keyboards, which were developed in the 1860s. Wired keyboards are almost always attached via USB. Wireless keyboards will often have a USB dongle that is attached to the computer but can also use Bluetooth. In addition to the standard QWERTY layout, modern computer keyboards often have separate cursor-movement and numerical keypads. The numerical keys in a row above182the alphabet keys send scan codes to the computer that are different from those sent by the numerical keypad. At the discretion of the programmer, any given application might require the use of only one of the two sets of numeric keys or allow the use of either. The IBM PC/AT keyboard had only 84 keys, lacking separate cursor-movement keys. These functions were superimposed on the numeric keypad only. The Num Lock key had to be toggled to switch between cursor movement and the numeric keypad. The 101-key keyboard did include these separate keys but still kept the Num Lock arrangement as well, and the popular 104-key Windows keyboard added Windows-specific keys to those 101 keys. Keyboards have also added function keys (not to be confused with the common laptop key labeled Fn), which are often placed in a row across the top of the keyboard above the numerical row. Key functionality can be modified by using one or more combinations of the Ctrl, Alt, Shift, and laptop Fn keys along with the normal QWERTY keys. Technically speaking, the keys on a keyboard complete individual circuits when each one is pressed. The completion of each circuit leads to a unique scan code that is sent to the keyboard connector on the computer system. The computer uses a keyboard controller chip or function to interpret the code as the corresponding key sequence. The computer then decides what action to take based on the key sequence and what it means to the computer and the active application, including simply displaying the character printed on the key. In addition to the layout for a standard keyboard, other keyboard layouts exist—some not nearly as popular, however. For example, without changing the order of the keys, an ergonomic keyboard is designed to feel more comfortable to users as they type. The typical human’s hands do not rest with the fingers straight down. Ergonomic keyboards, therefore, should not place keys flat and along the same plane. To accomplish that goal, manufacturers split the keyboard down the middle, angling keys on each side downward from the center. Doing so fits the keys to the fingers of the hands when they are in a relaxed state. Figure 3.42 shows an example of an ergonomic keyboard. Figure 3.42 An ergonomic keyboard 183 The Dvorak Simplified Keyboard, patented in 1936, was designed to reduce fatigue in the hands of typists by placing characters that are more commonly used in the home row, among other physiologic enhancements. The standard QWERTY layout was designed to keep the hammers of a typewriter from becoming entangled, but typewriters are essentially obsolete. Although the Dvorak keyboard makes logical sense, especially in light of the historic decline in manufacturing and sales of the classic typewriter, the QWERTY keyboard remains dominant. One reason why the Dvorak keyboard has failed to take over might be the loss of productivity to a touch-typist as they retrain on the new format. Mouse Although the computer mouse was born in the 1970s at Xerox’s Palo Alto Research Center (PARC), it was in 1984 that Apple made the mouse an integral part of the personal computer with the introduction of the Macintosh. In its most basic form, the mouse is a hand-fitting device that uses some form of motion-detection mechanism to translate its own physical two-dimensional movement into onscreen cursor motion. Many variations of the mouse exist, including trackballs, tablets, touch pads, and pointing sticks. Figure 3.43 illustrates the most recognizable form of the mouse. Figure 3.43 A computer mouse The motion-detection mechanism of the original Apple mouse was a simple ball that protruded from the bottom of the device so that when the bottom was placed against a flat surface that offered a slight amount of friction, the mouse would glide over the surface but184the ball would roll, actuating two rollers that mapped the linear movement to a Cartesian plane and transmitted the results to the software interface. This method of motion detection remains available today, although it’s fairly unpopular. Later technologies used optical receptors to catch LED light reflected from specially made surfaces purchased with the devices and used like a mouse pad. A mouse pad is a special surface that improves mechanical mouse traction while offering very little resistance to the mouse itself. As optical science advanced for the mouse, lasers were used to allow a sharper image to be captured by the mouse, providing more sensitivity in motion detection. Certain surfaces don’t lend themselves well to standard laser-mouse functionality, but a higher resolution version exists that can even track across the surface of glass. The mouse today can be wired to the computer system or connected wirelessly. A wired mouse typically uses a USB port, which also provides power. Wireless versions will have a USB dongle or connect via Bluetooth. They are powered with batteries, and the optical varieties deplete these batteries more quickly than their mechanical counterparts. The final topic is one that is relevant for any mouse: buttons. The number of buttons that you need your mouse to have is dependent on the software interfaces you use. For the Macintosh, one button has always been sufficient, but for a Windows-based computer, at least two are recommended—hence, the term right-click. Today, the mouse is commonly found to have a wheel on top to aid in scrolling and other specialty movement. The wheel has even developed a click in many models, sort of an additional button underneath the wheel. Buttons on the side of the mouse that can be programmed for whatever the user desires are more common today as well and can alarm the unsuspecting user the first time they grab such a mouse the wrong way. There are several variants on pointer devices, such as trackballs. A trackball is like an inverted mouse. Both devices place the buttons on the top, which is where your fingers will be. A mouse places its tracking mechanism on the bottom, requiring that you move the entire assembly as an analogue for how you want the cursor on the screen to move. In contrast, a trackball places the tracking mechanism, usually a ball that is about one inch in diameter, on the top with the buttons. You then have a device that need not be moved around on the desktop and can work in tight spaces and on surfaces that would be incompatible with the use of a mouse. The better trackballs place the ball and buttons in such a configuration that your hand rests ergonomically on the device, allowing effortless control of the onscreen cursor. Touch Pad Most modern laptops have a built-in pointing device that can take the place of a mouse. Touch pads are flat panels, which are most often positioned in the same plane as the keyboard—between the spacebar and the user—often with buttons that supply the left- and right-clicks of the mouse. The user controls the onscreen pointer by tracing its path on the surface of the touch pad, some of which include a tactile click feature that takes the place185of the left-button click. Some touch pads also dedicate an edge to the right-click function. Figure 3.44 shows a laptop touch pad with three buttons. Figure 3.44 A laptop touch pad Touch pads can be purchased as separate external devices for use with any computer that has an available port, often USB. These work with laptops and desktops alike. Regardless of the details surrounding the touch pad, Windows offers one or more tabs dedicated to the touch pad in the Mouse applet in Control Panel for use in configuring the various settings for it. Tabs added by the manufacturer of the hardware often include advanced configuration options, including those related to multitouch and motions. We will explore touch pad configuration options in Chapter 10, “Understanding Laptops.” Signature Pad At many medical offices, grocery stores, and other places of business, customers will be asked to sign receipts or documents. While some will have people sign a real piece of paper, many businesses are moving to the use of electronic signature pads. A signature pad uses very similar technology to a touch pad, in that contact on a flat surface is translated into electrical signals, which are sent to the processor. Signature pads often make use of a stylus, which is a pen-like device. Others can simply track the pattern of a signer’s finger. Generally speaking, the stylus-based models produce a more accurate representation of a person’s signature. If you’ve ever tried signing a signature pad with your index finger, it probably looked nothing like your normal signature. An example of a stylus-based signature pad is shown in Figure 3.45. 186 Figure 3.45 A Topaz Systems signature pad  Picture courtesy of TopazSystems.com Signature pads often attach via USB or through an Ethernet cable, although some serial port models exist. Wireless models may support Bluetooth or Wi-Fi network connections. Game Controller As long as there have been gaming applications for the personal computer, there have been standard and specialty controllers for some of those games. For the rest, the keyboard and mouse could be or had to be used for controlling the game. Two popular types of controllers have been the generic joystick, a controller with one or more buttons and a stick of varying length and girth, and the often-proprietary game controller. If you’ve played with a gaming console such as an Xbox, PlayStation, or Wii, you are familiar with the latter. They usually have function and directional buttons specific to the gaming console in use, and more recently contain motion sensors. Through the years, standardized PC connections have included the DA15 game port, also known as the joystick port, the RS-232 port, and the USB port. Figure 3.46 shows a wired joystick (called a Nunchuk, in Wii parlance) connected through the wireless controller for the Nintendo Wii video game console. 187 Figure 3.46 A proprietary (Nintendo Wii) gamepad Barcode or QR Scanner A barcode scanner (or barcode reader) is a specialized input device commonly used in retail and other industrial sectors that manage inventory. The systems to which the reader connects can be so specialized that they have no other input device. Barcode readers can use LEDs or lasers as light sources and can scan one- or two-dimensional barcodes. Barcodes encode simple information—strings of numbers or letters—based on line widths. Using a Barcode Reader in the VoIP Industry The VoIP industry relies on barcode readers to quickly scan in the MAC addresses of hundreds or thousands of desk sets from labels on their neatly stacked boxes before their deployment. Depending on the brand of equipment, the MAC addresses might be read in to populate a spreadsheet that is later used as input to the call management system during the identification of which directory numbers will be assigned to which physical devices. The same job done by hand could have untold issues caused by user error. 188 Barcode readers can connect to the host system in a number of ways, but serial connections, such as USB, are fairly common. If the system uses proprietary software to receive the reader’s input, the connection between the two might be proprietary as well. Classic software interfaces called for the reader to be plugged into the keyboard’s PS/2 connector using a splitter, or “wedge,” which allows the keyboard to remain connected. The scanner converts all output to keyboard scans so that the system treats the input as though it came from a keyboard. For certain readers, wireless communication with the host is also possible, using infrared, radio frequency (RF), Bluetooth, or Wi-Fi. With today’s smartphone technology being what it is, the built-in cameras can act as scanners, and the scanning app can interpret what the camera sees. In this way, Universal Product Code (UPC) barcodes, Quick Response (QR) codes, and other 2D matrix barcodes can be input and processed. The smartphone can then use its Internet access to launch the application associated with the text, such as a web browser or an email client. A QR code is an encoded image that allows the scanning application to decode large amounts of text. It can be used to represent simple text or popular strings, such as a website’s URL, a phone number, a GEO location, an email address, or an SMS message. Figure 3.47 is a simple QR code that will direct a QR-code reader app to the www.wiley.com website. Figure 3.47 A QR code