Roaming Policy Property

The roaming policy property determines how aggressively the device attempts to roam as the signal-to-noise (SNR) ratio of the transmission from an access point deteriorates.

The device assesses the SNR in terms of the SNR metric. For more information, refer to Acceptable Voice Quality. The device begins to look for another access point when the SNR value drops to a level specified by the Roaming Policy value.

The roaming policy value is an integer from 1 to 5, where 1 specifies the least aggressive roaming and 3,4, and 5 are the most aggressive. By default, the roaming policy for B3000n is 2 and V5000 is 3 meaning the Vocera devices roam when the SNR falls below 20dB or RSSI falls below -70dB respectively.

The following table shows the relationship between device SNR values and roaming policy. It also provides the typical SNR values at which the device initiates roaming. Vocera recommends that you set the roaming policy property on Vocera devices to a value that is appropriate for your RF cell size.

Roaming Policy Value	Typical B3000n/B3000 SNR when Roaming	Typical V5000 RSSI when Roaming	Description
1	18	- 75 dB	The lowest value used since voice quality is maintained when roaming is initiated.
2	20	- 73 dB	The device initiates roaming while voice quality is good on most networks.
3	22	- 70 dB	The default value that initiates roaming while voice quality is high. This value usually causes roaming that is too aggressive, but it may help roaming on a network with densely deployed APs. For information about data rates, refer to Overlapping Cells and Data Rates.
4	24	- 65 dB	This value initiates very aggressive roaming behavior and would not be used normally in a typical deployment.
5	26	- 60 dB	This value represents the highest available policy value and should be used only in conjunction with guidance from Vocera Technical Support when investigating roaming performance.

Note: The actual SNR values may vary slightly, due to environmental factors and dynamic changes in coverage.

If you are not satisfied with the roaming behavior of the device and want to adjust the roaming policy property, contact Vocera Technical Support.

To specify the roaming policy property, use the Badge Properties Editor (BPE) to set the roaming policy property to the appropriate value on all badges. For more information on setting roaming policy, refer to Vocera Badge Configuration Guide.