Page 226 of 910 Features
553-3001-365 Standard 4.00 August 2005
If an available resource cannot be found, the overflow tone is given. For most
installations, this approach works because all IP Phone users share the IP Line
DSP resources. The DSPs can be provisioned using a DSP-to-IP Phone ratio
similar to trunk resources, since the DSPs are used only for circuit-switched
access or conference calls.
When IP-to-PSTN calls are used, such as with ACD agents or other users who
consistently are using trunk resources when making calls, it becomes difficult
to provision the system in a way that guarantees an available DSP channel
when these users need it. If the other users suddenly make a lot of conference
calls or trunk calls, the DSP resources can deplete and as a result, calls cannot
be made. This occurs because all DSP channels are in one pool.
DSP resources and Private Zones
To address this situation, IP Line 4.5 provides the Private Zone Configuration
feature for DSP configuration and allocation to the zone configuration. This
feature enables the configuration of one or more gateway channels as a
private resource. This guarantees DSP availability for critical or ACD agent
IP Phone.
A zone can be configured as shared or private.
Shared Zone
The current default zone type is a Shared Zone. IP Phones configured in
Shared Zones use DSP resources configured in shared zones. If all the Shared
Zones’ gateway channels are used, the caller receives an overflow tone and
the call is blocked.
Select gateway channels in the following order:
• Select a channel from the same zone as the zone where the IP Phone is
configured.
• Select any available channel from the Shared Zones’ channels.
Private Zone
The Private Zone enables DSP channels configured in a Private Zone to be
used only by the IP Phones that have also been configured for that Private