Monday, November 30, 2009

Device Mobility

[notes]
Device mobility info – configures IP subnets and associates device pools to the IP subnets
Device mobility group – defines a logical group of sites with similar dialing patterns
Physical Location – geographically located device pools

Roaming Sensitive Settings – override the device level settings when a device is roaming within or outside a device mobility group

Device Mobility Related settings – will override the device level settings only when the device is roaming within a device mobility group

DTIM settings are global, not to be changed on a per WLAN basis.
RRM baseline level changed from -65dbm to -70dbm in 4.1.185 code

If RF-Group mode is disabled, the WLCs run computations based only on the neighbor data gathered from the APs connected to that WLC via LWAPP, trying to optimize the signal to -70dbm between APs.

Within an AP-group, there may be APs that do not see each other.  These APs form a logical RF sub-group whose RF parameters are calculated separately.

The RF Group leader uses the gathered values to determine whether another channel schema will result in an improvement of at least 5db SNR for the worst performing AP.
    Preference is given to APs based on utilization.  A less used neighbor has a higher likelihood of having its channel changed

show AP auto-RF IEEE {802.11a|802.11b} [AP-name]

Transmit power level assignment is controlled by the TPC algorithm that is run at fixed intervals of every 10 minutes by default.
TPC tries to adjust levels downward
There is a 6db hysteresis used built into the TPC algorithm to prevent it from continuously hunting for the -70dbm value.

Monitor intervals determine how often the APs stop serving clients to perform RRM & wireless duties.


No comments:

Post a Comment