Alvarion BreezeACCESS II System Manual page 185

Menus and Parameters
Default value: 512.
NOTE:
There is no aging time for SUs. An SU will be removed from the list of associated SUs
only upon occurrence of any of the following: (1) The AU received from another AU a
SNAP frame with the SU MAC address indicating that the SU has become associated
with the other AU, or (2) The AU has decided that the SU aged out following its failure
to acknowledge a certain number of consecutive frames transmitted to it.
Thus, the database of associated SUs may include units that are no longer associated
with the AU. If the number of associated SUs has reached the value of the Maximum
Number of Associations parameter, additional SUs can not be served by this AU. To
view the current number of associated SUs, use the Display Association Info option
in the MAC Address Database menu. To delete entries of SUs that are no longer active,
the AU must be reset.
WLAN Aging Time (AU only)– Displays the current Call Aging
Time parameter value and configures a new value. The AU
maintains a Call Information database that includes listings of the
SUs that are currently conducting a voice call. This database is used
to determine the number of active voice calls that are managed by
the AU at any given moment, allowing control of the number of
simultaneous voice calls (see Maximum Voice Sessions
parameters). In addition, the AU allocates prioritized channels to the
voice (RTP) packets of SUs included in the Call Information
database.
The SU is deleted from the Call Information database once it sends a
message that the call was terminated. Throughout the voice call, the
SU periodically transmits keep-alive (re-association) messages
approximately every ten minutes indicating that the call is still on. If
such messages are not received for a period defined by the Call
Aging Time parameter, the following will take place.
a The AU deletes the SU listing from the Call Information
database assuming that the call was improperly terminated
(e.g. reset or loss of synchronization).
b. For non-ACSE voice calls, a prioritized channel is no longer
allocated to the voice packets (although voice packets will still
get a relatively high priority).
c. ACSE voice calls will be terminated (no slot will be allocated for
the call).
The allowed range for the Call Aging Time parameter is 1 (no aging)
or 2-50,000 seconds. It is recommended to configure a call aging
time of at least 1200 (20 minutes).
The default value is 1800 seconds.
Maximum Voice Sessions – Applicable only for an AU that provides
services to Subscriber Units with voice capabilities. When the ACSE
voice scheduler option is enabled, this parameter is not applicable
and instead the Maximum ACSE Voice Sessions parameter is
used. The value of the Maximum Voice Sessions parameter
specifies the maximum number of simultaneous voice sessions that
BreezeACCESS Version 4.3 System Manual
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