User's Manual

Domains
There are three official MLPP domain names (MLPP_NETWORK_DOMAIN): DSN, DRSN and
ETS. Each has a pre-defined list of priorities.
Domain name Priorities
DSN
• Routine
• Priority
• Immediate
• Flash
• Flash-Override
DRSN
• Routine
• Priority
• Immediate
• Flash
• Flash-Override
• Flash-Override-Override
• Emergency
ETS
• Emergency
• Emergency
The default domain is DSN.
To configure the call precedence level properly, the precedence value configured should match
one of the precedence levels available for the MLPP_NETWORK_DOMAIN parameter.
If the MLPP_NETWORK_DOMAIN value does not match any of the values listed in the
preceding table, then the list of precedence levels specified for the DSN Network Domain is
applied.
Preemption
Higher precedence calls preempt calls lower in precedence when a user has no free call
appearances.
If an IP Deskphone reaches the maximum call appearance limit and a higher precedence call
is received, then one of the existing calls is preempted in order to present the higher
precedence incoming call. An incoming call with a precedence level less than or equal to the
already-received call precedence levels is not presented.
IM sessions cannot be preempted because they do not count as a call appearance.
Multi-Level Precedence and Preemption
SIP Software for Avaya 1100 Series IP Deskphones-Administration November 2012 209