1
Wireless Chapter 7
CCNA Exploration Semester 3
Modified by Profs. Ward
and Cappellino
2
Topics
Components and basic operation of wireless LANs
Basic WLAN security Configure and verify basic wireless LAN
access Troubleshoot wireless client access
3
Semester 3
LAN Design
Basic Switch Concepts
VLANs
VTP
STP
Inter-VLAN routing
Wireless-
Chp 7
4
Wireless Review
Wireless was covered in CSN208, therefore, only new material will be presented here Must have understanding of entire chapter Please see me, the curriculum or the CSN208
text with questions Review- what is an AP? Review- what is a wireless NIC?
5
Wireless router Acts as:
Router for use in ___________________ Ethernet ______________ and wireless __________________________
Configuration on both the ____________________ is necessary
Parameters: Mode refers to the 802.11a, b, g, or n Configure SSID – what is the SSID? Select channel within 2.4GHz band
_________________________ should be set to use _____________________________-
6
Channel Graph
7
Different 802.11 Wireless Topologies…
Ad Hoc Basis Service Set (BSS) Extended Service Set (ESS)
More to come on each of these…
8
______________ topology
WLAN operating with _________________
_________________ Negotiate parameters Independent basic
service set Area covered is basic
service area (_____)
9
__________________ topology
_________________ Access point _________
_______________________________________ for clients
Uses _________ mode Area covered is basic
service area (_______).
10
________________ topology
________________________________________
Access point manages parameters for clients
__________ mode used Area covered is extended
service area (_____).
A common distribution system allows multiple access points in an ESS to appear to be a single BSS.
11
Beacon and probe Discovering a WLAN and connecting to it involves the
following components: ________ - _________ used by the WLAN
networks to _____________________ Access point may send out a beacon at regular intervals for
________________________ _________ - Frames _____________________
________________________ Client sends a probe specifying the _____________
supported. ________________________ Client can send probe with no SSID to look for any network.
Access point may be configured to respond, or not.Components continued on next slide…
12
Authentication
Components cont… ______________ One of three ___________
__________________________ __________________________ ____________________________ 802.11 had two authentication mechanisms.
________ (Open Authentication) does not give privacy
Wired Equivalency Protection (__________) Newer and more secure authentication method:
Wi-Fi Protected Access (_________)
Components continued on next slide…
13
Association Components cont… _______________ - The process for _________
___________________________________________________________________ Request from client and response. Finalizes __________________ Finalizes ____________________ ________________________ ____________ the access point MAC address (_______) Access point maps a logical port known as the association
identifier (AID) to the WLAN client. Traffic can then flow between the two devices
14
Planning the WLAN
Implement a _____________________ prior to construction of a WLAN
RF is a shared medium so the ______________ ______________________ for RF Place AP:
Above obstructions/ at least 3 feet from metal obstructions Vertically and high up/in the ceiling. In locations where users will work.
Work out the coverage for each AP. ___________________________
15
Wireless Security/Protocol review
These topics are also a review of the same material covered in CSN208
Review- what are some security threats? Review- what are some disruptive attacks
that could affect a business? Review- what are some Wireless protocols
we have studied? Review- what type of encryption does
Wireless use?
16
Controlling Access to the Wireless LAN
Possibilities for controlling access: ___________________ - __________________________
from access points __________ considered a ___________________ since
SSID can still be easily discovered ____________________ - Tables are manually
constructed on the access point to _________________ __________________________________ _____________ considered a way to secure a WLAN since
______________________________ WLAN _____________________ - ________________ ______________________________ of the AP
17
Configuring Access Point
Remember: To configure and test incrementally Most access points have been _______________________
______________________ with the default settings ________________________________!
18
Basic Wireless Settings
_______________ – Lets you choose the right mode for your devices. B, G, N, mixed or BG mixed. You can disable wireless operation.
__________________ – should be changed from the default. ______________________________ on the
network. _____________ can be enabled or disabled.
19
More Basic Wireless Settings
Radio Band – For best performance, keep the __________. For Wireless-N devices only, select Wide -
40MHz Channel. If you selected Wide for the Radio Band, Select a
channel from the drop-down menu of the “Wide Channel” parameter
For Wireless-G and Wireless-B only, select Standard - 20MHz Channel. If you selected Standard for the Radio Band, Select a
channel from the drop-down menu of the “Standard Channel” parameter
See summary graphic next slide…
20
Summary of Linksys Settings
21
Configure Security on the Linksys
Security mode Mode parameters RADIUS Server IP address RADIUS Server Port Encryption Pre-shared Key Key Renewal
22
Configure Security on the Linksys cont…
Choose _____________________ if all client devices are able to use it. If some older devices do not support WPA2 then choose
the best security mode that is supported by all devices.
Encryption – _______________________. Use AES with WPA2.
23
Configure the client After the access point has been configured, you
need to ___________________________________ to allow it to connect to the wireless network.
First, scan for available WLAN’s and SSID’s If a WLAN does not show up on an auto scan- what
could be the problem? Proceed manually
Add a wireless network Enter the SSID Choose the authentication method Choose the encryption method Enter the network key.
Now confirm connectivity with the AP using ping
24
Troubleshooting _____________
Generally start with the ___________________ __________________ the TCP/IP stack…
Check the ________________________ then Update __________________
25
Troubleshooting – no connectivity
Check that the PC has an ___________ Try connecting the PC to the wired network
and ping a known address Try a ___________________. Reload drivers
as necessary. Check the ______________________
settings on the client. Do they match the access point?
26
Troubleshooting – poor connection
Check __________________ Check the ______________ on the client. Check for devices that might be causing
______________ (cordless phone, microwave oven etc).
27
Troubleshooting – additional questions
Are all devices in place? Are they all powered on? Are wired links working correctly? Is there a neighboring access point using an
overlapping wave band? Are access points badly placed?
Top Related