AudioCodes Mediant 600 - MLPP Parameters

SIP User's Manual 676 Document #: LTRT-83310
Mediant 600 & Mediant 1000
A.12.5.12 MLPP Parameters
The Multilevel Precedence and Preemption (MLPP) parameters are described in the table
below.
Table A-52: MLPP Parameters
Parameter Description
Web/EMS: Call Priority Mode
[CallPriorityMode]
Enables priority calls handling.
 [0] Disable = Disable (default).
 [1] MLPP = MLPP Priority Call handling is enabled. MLPP
prioritizes call handling whereby the relative importance of
various kinds of communications is strictly defined, allowing
higher precedence communication at the expense of lower
precedence communications. Higher priority calls override less
priority calls when, for example, congestion occurs in a network.
 [2] Emergency = Preemption of IP-to-Tel E911 emergency calls.
If the device receives an E911 call and there are unavailable
channels to receive the call, the device terminates one of the
channel calls and sends the E911 call to that channel. The
preemption is done only on a channel pertaining to the same
Trunk Group for which the E911 call was initially destined and if
the channel select mode (configured by the ChannelSelectMode
parameter) is set to other than “By Dest Number” (0). The
preemption is done only if the incoming IP-to-Tel call is
identified as an emergency call. The device identifies
emergency calls by one of the following:

The destination number of the IP call matches one of the
numbers defined by the EmergencyNumbers parameter.
(For E911, you must define this parameter with the value
"911".)

The incoming SIP INVITE message contains the
“emergency” value in the Priority header.
Notes:

Applicable to FXS/FXO, CAS, and ISDN interfaces.

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 initiated by the FXO
(i.e., Tel-to-IP calls), new incoming emergency IP-to-Tel
calls are dropped.

For more information, see 'Pre-empting Existing Call for
E911 IP-to-Tel Call' on page 313.
Web: MLPP Default
Namespace
EMS: Default Name Space
[MLPPDefaultNamespace]
Determines the namespace used for MLPP calls received from the
ISDN side and destined for the Application server. The namespace
value is not present in the Precedence IE of the PRI Setup
message. Therefore, the value is used in the Resource-Priority
header of the outgoing SIP INVITE request.
 [1] DSN = DSN (default)
 [2] DOD = DOD
 [3] DRSN = DRSN
 [5] UC = UC
Web/EMS: Default Call Priority
[SIPDefaultCallPriority]
Determines the default call priority for MLPP calls.
 [0] 0 = ROUTINE (default)
 [2] 2 = PRIORITY