Aastra 9143i Series Administrator's Manual page 257

Specific sets of SIP parameters are inter-dependent with each other. To prevent
conflicting parameter values from being applied, per-line values always take
precedence over the corresponding set of global values.
For example, if a parameter value is configured for one of the per-line sets, all
parameters from that set are applied and all parameters from the corresponding
global section are ignored, even if some of the parameters within the global set are
not defined in the per-line set.
SIP Precedence Example
The following example shows the SIP proxy feature and example schema for
storage and parsing of the SIP configuration parameters.
The following SIP configuration is assumed:
# SIP network block
sip proxy ip:
sip proxy port: 5060
sip registrar ip:
sip registrar port: 4020
sip line3 proxy ip: siparator.vonage.com
sip line3 proxy port: 0
Line3 specifies per-line values for proxy IP address and proxy port, so the phone
uses those parameter values for SIP calls made on that line. However, because
those parameters are part of the SIP network block, the phone does not apply any
of the global SIP network block parameters. So even though the global parameters
configure a SIP registrar, Line3 on the phone ignores all global network block
parameters. Since line3 does not contain a per-line SIP registrar entry, the phone
does not use a registrar for that line.
41-001160-03 Rev 00, Release 2.5
Configuring Network and Session Initiation Protocol (SIP) Features
10.30.11.154
10.44.122.37
Note: Global SIP parameters apply to all lines unless overridden by a
per-line configuration.
Per-line settings are configurable for lines 1 through 7.
Global SIP Settings
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