Cisco Cisco Catalyst 6500 Series 7600 Series Wireless Services Module (WiSM) Weißbuch
Wireless LAN Design Guide for High Density
Client Environments in Higher Education
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Wireless LAN Controller and Feature Specific Configuration Recommendations
Here are some specific configuration recommendations and their function for a high-density environment. This is not a list of
specific requirements and individual configuration details will likely be different.
specific requirements and individual configuration details will likely be different.
WLANs=>WLANs #n Advanced Tab
• MFP Client Protection - optional or disabled, disabled will lower overhead slightly
• Client load balancing - enabled
• Client BandSelect - enabled
Wireless=>Access Points=>802.11a/b=>Configure
• 11n Parameters – ClientLink enabled, Clientlink enables beamforming to the legacy client and is activated when the client SNR
• MFP Client Protection - optional or disabled, disabled will lower overhead slightly
• Client load balancing - enabled
• Client BandSelect - enabled
Wireless=>Access Points=>802.11a/b=>Configure
• 11n Parameters – ClientLink enabled, Clientlink enables beamforming to the legacy client and is activated when the client SNR
indicates a rate shift is needed. This will add 3-6 dB for the downstream to the client and likely prevent a rate shift
• RF Channel Assignment - Global
• TX Power Level Assignment - Global
Wireless=>Advanced=>
• Load Balancing: Adjust client window size for your environment. Default is 5, will need to be more in line with expected load
Wireless=>Advanced=>
• Load Balancing: Adjust client window size for your environment. Default is 5, will need to be more in line with expected load
levels of 30-50 clients. Maximum denial count can be adjusted, but the default is generally sufficient. Must be enabled or
disabled per SSID and WLAN.
disabled per SSID and WLAN.
• BandSelect: Default values should be good except for Acceptable Client RSSI. Set this to reflect the expected power levels in
the room. This will also prevent clients outside of the high-density area from being monitored in the queue.
Wireless=>802.11a/802.11b=>Network
Network – Data Rates
Network – Data Rates
• Mandatory = Client must support in order to associate
• Supported = Optional: client may rate shift to this rate if desired
• Disabled = Not supported on the radio
Recommendations: Set the minimum acceptable data rate for the cell as supported. Choose a higher data rate as the target
client speed and set as mandatory. The first or lowest mandatory rate is the speed at which beacons will be sent. The highest
mandatory rate is the speed at which multicast will be broadcast. The design for a high-density WLAN should use a minimum
mandatory data rate of 18 or 24 Mbps.
Wireless=>802.11a/802.11b=>RRM
RRM should be used to manage both power and channel within a high-density WLAN. This will ensure that power levels and
channel selection are optimized. RRM will monitor the OTA propagation and utilization metrics and adjust all APs based on
their view of one another for optimal bandwidth/performance. Refer to the WLC Configuration Guide for a complete discussion
regarding configuration.
• Supported = Optional: client may rate shift to this rate if desired
• Disabled = Not supported on the radio
Recommendations: Set the minimum acceptable data rate for the cell as supported. Choose a higher data rate as the target
client speed and set as mandatory. The first or lowest mandatory rate is the speed at which beacons will be sent. The highest
mandatory rate is the speed at which multicast will be broadcast. The design for a high-density WLAN should use a minimum
mandatory data rate of 18 or 24 Mbps.
Wireless=>802.11a/802.11b=>RRM
RRM should be used to manage both power and channel within a high-density WLAN. This will ensure that power levels and
channel selection are optimized. RRM will monitor the OTA propagation and utilization metrics and adjust all APs based on
their view of one another for optimal bandwidth/performance. Refer to the WLC Configuration Guide for a complete discussion
regarding configuration.
Specific recommendations for high-density WLAN deployments include:
Transmit Power Control Algorithm (TPC )
•
Min/Max power sets a limit on the minimum and maximum power that a radio can use. It overrides TPC recommendations
and effects only the local controller and associated APs.
and effects only the local controller and associated APs.
•
TPC power threshold is used to adjust the power at the edge of the cell. The default is -70 dBm. Tune for specific installation
requirements. It may be necessary to adjust the TPC power threshold in an environment with a ceiling over 25 feet high.
requirements. It may be necessary to adjust the TPC power threshold in an environment with a ceiling over 25 feet high.