AudioCodes Mediant 500 MSBR, Руководство пользователя

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Version 7.2 583 Mediant 500 MSBR
User's Manual 30. Configuring Supplementary Services
The device identifies the IP-to-Tel call as an emergency call if the destination
number matches one of these configured emergency numbers. For E911, you
must configure the parameter to "911".
Note:
•
The device also identifies emergency calls if the Priority header of the incoming
SIP INVITE message contains the “emergency” value.
•
This feature is applicable to the following interfaces:
√
FXO
√
ISDN
√
CAS
•
For Trunk Groups configured with call preemption, all must be configured to MLPP
[1] or all configured to Emergency [2]. In other words, you cannot set some trunks
to [1] and some to [2].
•
The global parameter must be set to the same value as that of the Tel Profile
parameter; otherwise, the Tel Profile parameter is not applied.
•
If you configure call preemption using the global parameter and a new Tel Profile
is subsequently added, the TelProfile_CallPriorityMode parameter automatically
acquires the same setting as well.
•
For FXO interfaces, the preemption is done only on existing IP-to-Tel calls. In
other words, if all the current FXO channels are busy with calls that were
answered by the FXO device (i.e., Tel-to-IP calls), new incoming emergency IP-to-
Tel calls are rejected.
30.12 Multilevel Precedence and Preemption
The device supports Multilevel Precedence and Preemption (MLPP) service. MLPP is a
call priority scheme, which does the following:

Assigns a precedence level (priority level) to specific phone calls or messages.

Allows higher priority calls ( precedence call ) and messages to preempt lower priority
calls and messages (i.e., terminates existing lower priority calls) that are recognized
within a user-defined domain (
MLPP domain ID ). The domain specifies the collection
of devices and resources that are associated with an MLPP subscriber. When an
MLPP subscriber that belongs to a particular domain places a precedence call to
another MLPP subscriber that belongs to the same domain, MLPP service can
preempt the existing call that the called MLPP subscriber is on for a higher-
precedence call. MLPP service availability does not apply across different domains.
MLPP is typically used in the military where, for example, high-ranking personnel can
preempt active calls during network stress scenarios such as a national emergency or
degraded network situations.
MLPP can be enabled for all calls, using the global parameter, CallPriorityMode, or for
specific calls using the Tel Profile parameter, CallPriorityMode.