1. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE I Chapter 6 1 Wireless Router LAN Switching and Wireless – Chapter 7

2. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 2 Objectives  Describe the components and operations of basic wireless LAN topologies.  Describe the components and operations of basic wireless LAN security.  Configure and verify basic wireless LAN access.  Configure and troubleshoot wireless client access.

3. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE I Chapter 6 3 Introduction to Wireless LAN

4. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 4 Wireless LANs (WLANs)  Most business networks rely on switch-based LANs for day-to-day operation inside the office.  However, workers are becoming more mobile and want to maintain access to their business LAN resources from locations other than their desks.

5. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 5 Explain the Components and Operations of Basic Wireless LAN Topologies  Wireless Technology: The mix of wireless technologies in different types of networks allows workers to be mobile.

6. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 6 Explain the Components and Operations of Basic Wireless LAN Topologies  Describe the 802.11 wireless standards

7. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 7 Explain the Components and Operations of Basic Wireless LAN Topologies

8. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 8 Explain the Components and Operations of Basic Wireless LAN Topologies  Describe the components of a 802.11-based wireless infrastructure

9. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 9 Explain the Components and Operations of Basic Wireless LAN Topologies  wireless NIC: the device that makes a client station capable of sending and receiving RF signals.  Like an Ethernet NIC, the wireless NIC, using the modulation technique it is configured to use, encodes a data stream onto an RF signal.  Wireless NICs are most often associated with mobile devices, such as laptop computers, many manufacturers have begun building the wireless NIC right into the laptop.

10. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 10 Explain the Components and Operations of Basic Wireless LAN Topologies  Describe how wireless networks operate

11. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 11 Explain the Components and Operations of Basic Wireless LAN Topologies

12. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 12 Explain the Components and Operations of Basic Wireless LAN Topologies

13. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 13 Explain the Components and Operations of Basic Wireless LAN Topologies

14. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 14 Explain the Components and Operations of Basic Wireless LAN Topologies  Client and Access Point Association process are as follows: –Beacons - Frames used by the WLAN network to advertise its presence. –Probes - Frames used by WLAN clients to find their networks. –Authentication - A process which is an artifact from the original 802.11 standard, but still required by the standard. –Association - The process for establishing the data link between an access point and a WLAN client.

15. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 15 Explain the Components and Operations of Basic Wireless LAN Topologies  The primary purpose of the beacon is to allow WLAN clients to learn which networks and access points are available in a given area, thereby allowing them to choose which network and access point to use. Access points may broadcast beacons periodically.

16. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 16 Explain the Components and Operations of Basic Wireless LAN Topologies

17. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 17 Explain the Components and Operations of Basic Wireless LAN Topologies

18. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 18 Explain the Components and Operations of Basic Wireless LAN Topologies

19. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 19 Explain the Components and Operations of Basic Wireless LAN Topologies  Describe how to plan a wireless LAN

20. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 20 Explain the Components and Operations of Basic Wireless LAN Topologies

21. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE I Chapter 6 21 Wireless LAN security

22. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 22 Explain Wireless LAN Security

23. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 23 Explain the Components and Operations of Basic Wireless LAN Security  One of the more sophisticated attacks an unauthorized user can make is called a man-in-the-middle (MITM)  Attackers select a host as a target and position themselves logically between the target and the router or gateway of the target  The attacker can carry out wireless MITM attacks, using the laptop NIC acts as an access point.  A hacker selects a station as a target and uses packet sniffing software, such as Wireshark, to observe the client station connecting to an access point.  To defeat the MITM attacks, you must authenticate users on your WLAN. When all legitimate users are known, you then monitor the network for devices and traffic that is not supposed to be there.

24. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 24 Explain the Components and Operations of Basic Wireless LAN Security  Describe the threats to wireless LAN security

25. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 25 Explain the Components and Operations of Basic Wireless LAN Security

26. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 26 Explain the Components and Operations of Basic Wireless LAN Security  Describe the wireless protocols. The description will include a description of 802.1x, a comparison of WPA and WPA2 as well as comparison of TKIP and AES

27. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 27 Explain the Components and Operations of Basic Wireless LAN Security  Describe how to secure a wireless LAN from the key security threats

28. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 28 Summary  Wireless LANs use standards such as IEEE 802.11a IEEE 802.11b IEEE 802.11g IEEE 802.11n  Basic Service set –Mobile clients use a single access point for connectivity  Extended service set –Multiple access point that share an SSID

29. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 29 Summary  WLAN security practices/methods include –MAC address filtering –SSID making –Implementing WPA2  Configuration of wireless NIC and access point –Configure both of them the same way SSID –Ensure that the latest firmware is installed  Troubleshooting WLANs include doing the following: –Check channel setting –Check for interference

30. © 2006 Cisco Systems, Inc. All rights reserved.Cisco PublicITE 1 Chapter 6 30