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Review Questions 57 18. Power sourcing equipment delivers which of the following? A. RF power to the access point B. DC power to the end device C. RF power to an antenna D. DC power to an antenna 19. Which access point mode involves connecting the access point to a distribution system for user access to the LAN? A. Bridge only mode B. Repeater only mode C. Root access point mode D. Access mode 20. Which of the following are midspan PoE devices? (Choose 2.) A. Single port injectors B. Multiport injectors C. Endpoint injectors D. Endspan injectors 38893c02.indd 57 5/18/09 4:37:34 PM 58 Chapter 2 N Wireless LAN Infrastructure Devices Answers to Review Questions 1. D, E. Wireless LAN technology functions at Layer 1 and Layer 2 of the OSI model. 2. D. In computer terminology, half duplex is two-way communication but only one way at a time. Full duplex is two-way communication in both directions simultaneously. 3. C. An autonomous access point is an intelligent, self-contained network infrastructure device. Lightweight access points (also called thin access points) work with a wireless LAN controller/switch. 4. A, C, D. A, C, and D are correct. SOHO access points typically are managed from a web browser and do not have a command-line interface feature. 5. B, C . Bridges must be on the same RF channel and have the same SSID in order to commu- nicate. 6. B, E. Wireless repeaters do extend the cell size and will potentially allow more users to connect. However, using a wireless repeater will decrease throughput. 7. B. A wireless LAN controller/switch uses centralized administration, not distributed administration. 8. B. Many SOHO access points use 15dBm or 32mW for transmit output power. 9. C. The PoE standard specifies 48 VDC as nominal. The range is 32–57 VDC. 10. A. A midspan device will inject power into an Ethernet cable. Endpoint power is delivered directly from a switch or controller. 11. B. Layer 2 is the Data Link layer. A MAC address is a unique identifier of the network card. 12. A, C. SOHO use HTTP or HTTPS for configuration. Enterprise can also use CLI. SMTP is Simple Mail Transfer Protocol. 13. B. An administrator should avoid configuring an access point from the wireless side of the network unless absolutely necessary. 14. A, B. Depending on the specific function, APs operate at Layers 1 and 2. Repeaters function only at Layer 1. 15. A, B, D. Enterprise access points have adjustable output power. Power sourcing equipment is used in PoE to deliver power and data. 16. B. VLANs involve logical separation of ports. 17. A. A lightweight access point connected to a port on the switch is considered to have direct connectivity. 18. B. PSE delivers DC power, not RF power. The DC power is delivered to an end device such as an access point. 38893c02.indd 58 5/18/09 4:37:35 PM Answers to Review Questions 59 19. C. Root access point is the default mode in most cases. An access point in root access point mode allows users to connect to the network. 20. A, B. Single port and multiport injectors combine power and data in the same cable. End- point power is out of the switch port. There is no such thing as an endspan injector. 38893c02.indd 59 5/18/09 4:37:35 PM 38893c02.indd 60 5/18/09 4:37:35 PM Chapter 3 Wireless LAN Client Devices THE FOLLOWING CWTS EXAM OBJECTIVES ARE COVERED IN THIS CHAPTER: Identify the purpose, features, and functions of the follow- ing client devices. Choose the appropriate installation or configuration steps in a given scenario. PC Cards (ExpressCard, CardBus, and PCMCIA) USB2, CF, and SD devices PCI, Mini-PCI, and Mini-PCIe cards Workgroup bridges Client utility software and drivers 38893c03.indd 61 5/18/09 4:51:23 PM Client devices are often thought of as computers—either desk- top or notebook—connected to a network. However, there are many other devices, both wired and wireless, that can connect to a computer network. Wireless LAN client devices include vari- ous types of computers, scanners, print servers, cameras, and other devices that are used to send data to a computer network. This chapter will look at the features of various wire- less LAN client adapter types and the software for configuration and management of these devices. Devices that connect to wireless networks use various types of adapters. Which adapter is used depends on the device it connects to. You can connect to such devices as a notebook PC, pocket PC, desktop computer, or barcode scanner. Wireless LAN adapters are avail- able in various types, both external and internal. External adapters connect either to an available port or into a slot in the device. Examples of external adapter types are: PCMCIA ExpressCard USB 2.0 CompactFlash (CF) Some devices use internal adapters that may require some level of disassembly or removal of a panel prior to the installation. Examples of internal adapter types are: PCI Mini-PCI Mini-PCIe Wireless LAN client adapters differ from other networking adapters (such as Ethernet adapters) because they contain radio hardware. The radio hardware uses radio frequency (RF) to send the computer data over the air. Chapter 4, “Radio Frequency (RF) Fundamen- tals for Wireless LAN Technology,” will discuss RF fundamentals in more detail. PCMCIA PCMCIA technology was developed in the early 1990s because the portable computer industry demanded smaller, lighter, and more mobile technology. The international stan- dards organization developed to promote the growth of such technology is the Personal Computer Memory Card International Association (PCMCIA). 38893c03.indd 62 5/18/09 4:51:23 PM PCMCIA 63 Features of PCMCIA Cards The PCMCIA standard addresses three types of cards—Type I, Type II, and Type III. These cards are named after the PCMCIA organization that promotes this card technology and is responsible for the standards. You might also see the term PC Card used to describe these cards. PC Card describes the physical card or peripheral. All three types are the same width and length and have a 68-pin connector. Figure 3.1 shows an example of a PCMCIA card that allows a computer to connect to a wireless network. FIGURE 3.1 Netgear WN511T Wireless PCMCIA adapter The only difference among the three types of cards is their thickness. Table 3.1 lists the different thickness and common uses of the card types. TABLE 3.1 Features of the Three Types of PCMCIA Card Card Type Thickness Common Use Type I 3.3 millimeters RAM, flash, OTP, and SRAM memory cards Type II 5.0 millimeters LANs, data/fax modems, and mass storage I/O devices Type III 10.5 millimeters Rotating mass storage devices 38893c03.indd 63 5/18/09 4:51:23 PM 64 Chapter 3 Wireless LAN Client Devices There are five versions of the PCMCIA standard. The release numbers are 1.0, 2.0, 2.1, 5.0, and 8.0. Releases 1.0 through 2.1 support 16-bit applications. Releases 5.0 and up address a 32-bit interface. For additional details on the PCMCIA releases, visit the PCMCIA website at www.pcmcia.org. Installation and Configuration of PCMCIA Cards Installation of a PCMCIA card is a fairly simple process. The first consideration is to verify the physical characteristics of the card, such as the type (Type I, II, or III) and device in which it will be used—a notebook computer, for example. The devices need to be physically compatible with each other to ensure correct operation. Another consideration is the device driver. A device driver is software required for a component such as a PCMCIA card to communicate with the computer operating system. The installer should have the latest ver- sion of the device driver accessible. The card comes with an installation CD (compact disc) that contains the device driver. It is best to follow the manufacturer’s installation recom- mendations for the installation process, which may involve updating the driver from the manufacturer’s website. It is important to verify compatibility and minimum system requirements prior to installing a wireless network adapter in a device. Refer to the owner’s manual or manufacturer’s website for this information. Configuration Using Installer Software In many cases, a user will be required to first install a software program from the card manufacturer. This software will usually load the device driver within the computer operat- ing system and install the configuration utility for the card. Configuration Using a Wizard In some cases, when the PCMCIA card is inserted into the correct slot, the computer oper- ating system will automatically install the required device driver. If the operating system cannot find the correct driver, the user will be prompted to search the Internet or insert a CD or other source from the manufacturer with the software device driver. Figure 3.2 shows a wizard that the Microsoft Windows XP operating system will display to help load the device driver. The manual device driver installation process described in Exercise 3.1 for PCMCIA is also applicable for other types of adapters explained in this chapter. Exercise 3.1 illustrates how a common PCMCIA wireless LAN card will be installed. Do not insert the adapter until instructed to do so by the installation program. 38893c03.indd 64 5/18/09 4:51:23 PM PCMCIA 65 FIGURE 3.2 Microsoft Windows XP Found New Hardware Wizard EXERCISE 3.1 PCMCIA Card Installation Steps The following steps are typical for installation of a PCMCIA wireless LAN card. Installation steps are specific to the manufacturer, and it is recommended to follow the manufacturer’s installation instructions. Always read the manufacturer’s manual regarding setup and safety before attempting installation. 1. Insert the Setup CD-ROM into the CD-ROM drive. The program should start automati- cally, and a welcome screen may appear. The graphic shows the welcome screen for the Linksys Wireless-G Notebook Adapter Setup Wizard. 38893c03.indd 65 5/18/09 4:51:23 PM 66 Chapter 3 Wireless LAN Client Devices 2. After reading and accepting the license agreement, click to continue the installation and the program will begin copying the files onto your computer. 3. The setup program will now prompt the installer to install the adapter into the PC. This image illustrates inserting the adapter into a notebook computer. 4. After the card has been identified, the program will copy the driver files to the computer. 5. The setup program will display the available wireless networks in the area or mode for connecting. Create a profile by selecting or typing in the desired wireless net- work. The following image shows the Linksys Setup Wizard’s Wireless Mode connec- tion screen. EXERCISE 3.1 (continued) 38893c03.indd 66 5/18/09 4:51:24 PM [...]... length and width, 36 mm × 43mm The only difference is the thickness Table 3. 2 lists physical characteristics and typical uses of CompactFlash cards Ta b l e 3 2 Characteristics and Uses of CF Cards Card Type Thickness Common Use Type I 3. 3 millimeters RAM, flash memory cards Type II 5.0 millimeters Wireless LANs, microdrives Figure 3. 6 shows the front and back of a CompactFlash wireless LAN card... for external connectors, television tuners, and wireless broadband, whereas standard modules will have specific functionality such as a wireless network adapter Figure 3. 3 shows the four types of ExpressCards 54mm extended (external connectors) 34 mm extended (external connectors) 34 mm 54mm Image courtesy of PCMCIA Used by permission F i g u r e 3 3 The four types of ExpressCard module ... 802.11a/b/g wireless connectivity F i g u r e 3 6 Motorola LA-5 137 IEEE 802.11a/b/g CompactFlash card 74 Chapter 3 Wireless LAN Client Devices n For additional information regarding this technology, visit the CompactFlash organization at www.compactflash.org Installation and Configuration of a CF Card Installing a CF IEEE 802.11 wireless LAN card differs from some of the previous installation examples... Installing a PCI card may require tools and the installer might need to remove the cover from the desktop computer case Figure 3. 8 shows an example of an IEEE 802.11 wireless PCI card 76 Chapter 3 Wireless LAN Client Devices n F i g u r e 3 8 Netgear WG311T IEEE 802.11g wireless PCI adapter Features of PCI PCI connects to what is known as a data bus In basic terms, a data bus allows connection... segment to wireless Figure 3. 11 illustrates an application of a wireless workgroup or client bridge 82 Chapter 3 Wireless LAN Client Devices n F i g u r e 3 11 Typical application for a wireless workgroup/client bridge Ethernet segment with connected devices Workgroup or client bridge Access point Ethernet segment with connected devices Features of Workgroup/Client Bridges The wireless workgroup... as modem or computer network access Mini-PCIe cards are 30 mm × 56mm in length and width and have a 52-pin edge connector, consisting of two staggered rows on a 0.8mm pitch These cards are 1.0mm thick excluding components Table 3. 3 summarizes the features of Mini-PCI and Mini-PCIe cards 80 Chapter 3 Wireless LAN Client Devices n Ta b l e 3 3 Features of Mini-PCI and Mini-PCIe Cards Card... into the motherboard, system board, or main board As PC technology evolved, so did the data bus architecture, going to 32 -bit and now 64-bit bus Wireless networks are no stranger to PCI Even though wireless is often thought of as portable or mobile, in many cases stationary desktop computers can utilize wireless LAN connectivity through the use of wireless PCI interface cards PCI-SIG (Peripheral Component... install and configure the wireless PCI adapter The installation wizard will appear on the screen 2 The setup program will copy the required files to the desktop computer 78 Chapter 3 Wireless LAN Client Devices n E x e r c i s e 3 3 ( c o n t i n u e d ) Turn off the computer to install the card Once the computer is turned off, unplug the power cord from the wall jack 3 Open the case and identify... installed will ensure correct operation and sometimes add additional features Figure 3. 13 shows a device listing in the Windows XP operating system F i g u r e 3 1 3 Microsoft Windows XP Device Manager Client Utility Software All IEEE 802.11 wireless LAN cards require configuration in order to connect to a wireless network The configuration capabilities of device drivers are usually very limited... Figure 3. 15 shows an enterprise-grade client utility F i g u r e 3 1 5 Proxim client utility for 8480-WD 802.11a/b/g 86 Chapter 3 Wireless LAN Client Devices n Third-Party Client Utilities Another option for a wireless LAN adapter client utility is a third-party utility built into a computer operating system Recent versions of the Microsoft Windows operating system— Windows XP and Vista, for example—have . thing as an endspan injector. 38 893c02.indd 59 5/18/09 4 :37 :35 PM 38 893c02.indd 60 5/18/09 4 :37 :35 PM Chapter 3 Wireless LAN Client Devices THE FOLLOWING CWTS EXAM OBJECTIVES ARE COVERED IN. Figure 3. 8 shows an example of an IEEE 802.11 wireless PCI card. 38 893c 03. indd 75 5/18/09 4:51:27 PM 76 Chapter 3 Wireless LAN Client Devices FIGURE 3. 8 Netgear WG311T IEEE 802.11g wireless. I/O devices Type III 10.5 millimeters Rotating mass storage devices 38 893c 03. indd 63 5/18/09 4:51: 23 PM 64 Chapter 3 Wireless LAN Client Devices There are five versions of the PCMCIA standard.