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Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Wireless Networking Chapter 15 © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Objectives • Explain wireless networking standards • Describe the process for implementing Wi-Fi networks • Describe troubleshooting techniques for wireless networks © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Overview © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Introduction to wireless networking • Wireless network uses radio frequency (RF) waves as the media – – – – – Convenient and sometimes the only option Same OSI layers as wired networks Same upper-layer protocols as wired networks Different methods for accessing the media Wi-Fi IEEE 802.11 wireless Ethernet standards © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Three parts to Chapter 15 • Wi-Fi standards • Implementing Wi-Fi • Troubleshooting Wi-Fi © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Wi-Fi standards © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wi-Fi IEEE 802.11 standards – 802.11a – 802.11b – 802.11g – 802.11n • Certified by 300-member Wi-Fi Alliance – Members design and manufacture Wi-Fi products – Certification should ensure compatibility © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • 802.11 – Standards define how devices communicate – Some define how to secure communications – Each sub-standard by a IEEE subcommittee – Wireless Fidelity (Wi-Fi) – 802.11 established baseline features © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Hardware – Adapters • Wireless Ethernet NICS • PCI, PC Card, external USB – Wireless access point (WAP) • Basic WAP operates like a hub at Layer 1 • Often multiple devices in one box – High-speed hub or switch – Bridge – Router © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.1 Wireless PCIe NIC © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.2 External USB wireless NIC © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.3 Linksys device that acts as wireless access point, switch, and DSL router © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Software – Wireless device drivers – Wireless configuration utilities – Link state – Signal strength – Other settings • Wireless network modes • Security • Power-saving options © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.4 Wireless client configuration utility © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wireless network modes – Ad hoc mode • Also called peer-to-peer mode • Uses a mesh topology • Independent Basic Service Set (IBBS) © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.5 Wireless ad hoc mode network © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wireless network modes (cont.) – Infrastructure mode • Uses one or more access points • Similar to a wired star topology • Basic service set (BSS) – Serviced by a single WAP • Extended service set (ESS) – Serviced by two or more WAPs © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.6 Wireless infrastructure mode network © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Range – Hard to define – 802.11 “around 150 feet” – Affected by environmental factors © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Basic Service Set Identifier (BSSID) – Most basic infrastructure mode network – BSS is one WAP and one or more nodes – BSSID same as the MAC address of WAP – IBSS nodes (ad hoc mode) 48-bit string – BSSID in every frame © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Service Set Identifier (SSID) – Another level of naming – Standard name applied to BSS or IBSS – Sometimes called a network name © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Extended Service Set Identifier (ESSID) – Wi-Fi network with multiple WAPs (ESS) – Most Wi-Fi devices use term SSID © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Broadcasting frequency – Potential for interference from other wireless devices – Tech must know frequencies of other wireless devices – Original 802.11 standards use 2.4-GHz frequency band © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Broadcast methods – Original IEEE 802.11 standard used spreadspectrum radio waves • Broadcasts data in small, discrete chunks • Used different frequencies within a range • Three different spread-spectrum broadcasting methods © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Direct-sequence spread-spectrum (DSSS) – Sends simultaneously on different frequencies – Early 802.11 standards used this – Uses ~22 MHz of bandwidth – Capable of greater data throughput than OFDM – More prone to interference than FHSS © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Frequency-hopping spread-spectrum (FHSS) – Hops from frequency to frequency – Sends on one frequency at a time – Uses less bandwidth than DSS (~1MHz) © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Orthogonal frequency-division multiplexing (OFDM) – Latest method – Combines multiple frequencies of DSSS with FHSS’s hopping capability – Later 802.11 standards use this © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Channels – A portion of the spectrum – 802.11 standard defined 14 channels – Different countries may limit channels – In the U.S., WAP may use channels 1 – 11 – There is overlap – Do not use close channels on nearby WAPs – Most WAPs default to channel 1, 6, or 11 © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • CSMA/CA – Carrier sense multiple access/collision avoidance – Access method • Allows multiple devices to share network media – Wireless devices cannot detect collisions – Two collision avoidance methods • Distributed Coordination Function (DCF) • Point Coordination Function (PCF) © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • 802.11b – Data throughput up to 11 Mbps – Range up to 300 feet – Popular • 2.4-GHz frequency is crowded • More likely to have interference from other wireless devices © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • 802.11a – Devices on market after 802.11b – Different from all other 802.11 standards • 5-GHz frequency range • Up to 54 Mbps • Short range (~150 feet) • Never as popular as 802.11b • Incompatible with 802.11b © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Table 15.1 802.11 Summary Standard Frequency Spectrum 802.11 Table 15.2 2.4GHz DSSS Table 15.3 2.4GHz DSSS ~300′ 802.11 Speed Range Compatibility 11 Mbps ~300′ 802.11b 802.11a Summary Standard Frequency Spectrum 802.11a 2 Mbps Range Compatibility 802.11b Summary Standard Frequency Spectrum 802.11b Speed 5.0GHz © 2012 The McGraw-Hill Companies, Inc. All rights reserved. DSSS Speed Range Compatibility 54 Mbps ~150′ 802.11a Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • 802.11g – Up to 54 Mbps – Range of 802.11b (~300 feet) – Backward compatible with 802.11b – WAP can service both 802.11b and 802.11g – All 802.11g network runs in native mode – Add 802.11b devices • Mixed mode • All communications drop to 11 Mbps max © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • 802.11n – Faster and newer antenna technology – Most devices must use multiple antennas – Multiple in/multiple out (MIMO) – Up to 600 Mbps theoretically – Many WAPs use transmit beamforming – Dual-band WAPs run at 5 GHz and 2.4 GHz – Some WAPs support 802.11a devices © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Table 15.4 802.11g Summary Standard Frequency Spectrum Speed 802.11g 2.4GHz Table 15.5 OFDM Range Compatibility 54 Mbps ~300′ 802.11b/g 802.11n Summary Standard Frequency Spectrum 802.11n 2.4GHz1 OFDM Speed Range Compatibility 100+Mbps ~300′ 802.11b/g/n2 1 Dual-band 802.11n devices can function simultaneously at both 2.4- and 5.0-GHz bands. 2 Many dual-band 802.11n WAPs support 802.11a devices as well as 802.11b/g/n devices. This is not part of the standard, but something manufacturers have implemented. © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wireless networking security – Problem • Easy-to-install devices have no default security • Network data frames are in radio waves – Three wireless security methods • MAC address filtering • Wireless authentication • Data encryption © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • MAC address filtering – Limits access to specific NICs – “Accepted users” list of MAC addresses – List stored in WAP – Rejects frames with other MAC addresses – Alternatively create exclusion list – Problem: hackers can spoof MAC addresses – MAC address must be updated for changes © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wireless authentication – Users with proper credentials get access – Can use a centralized security database – Requires extra steps for wireless users – 802.1X standard • RADIUS server • Extensible Authentication Protocol (EAP) password encryption © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wireless authentication (cont.) – RADIUS server • Provides authentication for network access • Enables access to user’s rights on network • Client computer is called a supplicant • WAP is the Network Access Server (NAS) • NAS contacts RADIUS server • RADIUS server checks security database • User given access if credentials are correct © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.7 Authenticating using RADIUS © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Wireless authentication problem areas – Connection must be secure • PPP between supplicant and WAP/NAS • IPsec between WAP/NAS and RADIUS server • RADIUS server uses an authentication protocol – EAP-TLS – EAP-TTLS – PEAP • WAP and wireless NICs must use same authentication protocol © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.8 Authentication using RADIUS with protocols in place © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.9 Setting EAP authentication scheme © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Data encryption – Wired Equivalent Privacy (WEP) • 64- or 128-bit encryption algorithm (24-bit IV) • Problems – Easily cracked – Size of key is a weakness (40- & 104-bit keys) – Weak implementation of RC4 protocol – Key is static and shared between all devices – No user authentication – only nodes by MAC © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Data encryption (cont.) – Wi-Fi Protected Access (WPA) • Dynamic encryption key generation – Issued per user and per session • Temporal Key Integrity Protocol (TKIP) • 128-bit encryption key • Problem: key can be broken © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Data encryption (cont.) – Wi-Fi Protected Access 2 (WPA2) • Amendment of 802.11 standard by 802.11i – Issued per user and per session • Uses Advanced Encryption Standard (AES) – 128-bit block cipher – Not completely hack proof – Deters casual hackers • Adding a RADIUS server for authentication enables WPA2-Enterprise (vs. WPA2-PSK in SOHO networks) © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Power over Ethernet (PoE) – Power and Ethernet signals via Ethernet ports – Good for WAPs far from power outlets – Both WAP and switch must comply with PoE © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Implementing Wi-Fi © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Performing a site survey – What wireless devices are already there? • Radio bands in use • Existing SSIDs and channels • Unique SSIDs • Separate channels within same radio band – Locate interference sources • Create sketch and identify interference sources • High-interference area may require 802.11n • May need multiple WAPs to avoid dead zones © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.10 Site survey with interference sources noted © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Installing the client – Read instructions with NIC • Install bus NIC and attach antenna • Special instructions for USB NIC – Install drivers and software first – Then connect NIC © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.11 Wi-Fi NIC installed © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Setting up an ad hoc network – Set NICs for ad hoc mode – SSID – IP addresses – Channel – Sharing © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.12 Selecting ad hoc mode in wireless configuration utility © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Setting up an infrastructure network – Placing the access point • Omnidirectional and centered – Radio waves flow outward – Standard straight-wire dipole antennas • Off-center position • Gaining gain • Focusing the wave with directional antenna © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.13 Room layout with WAP in the center © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.14 Replacement antenna on a WAP © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Setting up an infrastructure network (cont.) – Access point configuration • Configure the SSID (ESSID) and beacon • Configure MAC address filtering • Configure encryption • Configure channel and frequency • Configure the client © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.15 Security login for Linksys WAP © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.16 Linksys WAP setup screen © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.17 Setting the beacon interval © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.18 MAC address filtering configuration screen for a Linksys WAP © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.19 Encryption key configuration screen on Linksys WAP © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.20 Encryption screen on client wireless network adapter configuration utility © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.21 Encryption screen with RADIUS option © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.22 Changing the channel © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.23 Selecting frequency © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.24 Typing in an SSID manually © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Extending the network – Adding a WAP – Wireless bridges • Point-to-point • Point-to-multipoint – Repeating bridges – Bridges with access point and router functions © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Verify the installation – Move traffic between computers – Always verify installation before leaving © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.25 Linksys wireless bridge device © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Troubleshooting Wi-Fi © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Logical troubleshooting steps – What is the scope of the wireless problem? • Who is affected – One wireless client? – All wireless clients? • What is the nature of the problem? – Which network services do/don’t work? – If some work, but others don’t, it is not a network problem • When did problem start? © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Hardware troubleshooting – Like PC troubleshooting – Detect driver or resource problems with Device Manager • If necessary, reinstall the device driver • If necessary, reset the IRQ resources • Device not present? – Check connection on USB – Restart PC/Laptop to enable detection © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Software troubleshooting – Wireless adapter configuration • User vendor’s driver and configuration utility • Use Device Manager to uninstall and install vendor driver and utility – WAP’s firmware version • Symptom: client connects, but slow speed • Update access point’s firmware © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Connectivity troubleshooting – Not connecting automatically and quickly – Causes • Incorrect configuration • Low signal strength or Interference • Multipath (signal bouncing) causing multipath null spot • Overlapping WAP signals when not broadcasting SSID ( causes SSID mismatch errors) © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Connectivity troubleshooting (cont.) – Solutions • Higher-gain antennas • Move PC or WAP • Put WAPs on different channels • Move the interference © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) Figure 15.26 Windows XP Professional’s wireless configuration utility © 2012 The McGraw-Hill Companies, Inc. All rights reserved. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks, Third Edition (Exam N10-005) • Configuration troubleshooting – Check SSID • Must be identical on all devices – Check MAC address filter list for new NICs – Check security configuration • All wireless nodes and WAPs must match • Check for mistyped encryption key © 2012 The McGraw-Hill Companies, Inc. All rights reserved.