Aastra Telecom SISIP 57I CT - Manual (Page 281)

Operational Features
41-001160-00, Rev 01 Release 2.0 5-153
Operational IP Phone Features
Operational IP Phone Features Priority Alerting
Priority alerting on the IP phones is a feature that allows incoming calls to trigger
pre-defined ringing or call waiting alert tones.
You can enable or disable priority alerting on the IP phone for the Asterisk,
Broadworks, and Sylantro servers using the configuration files and the Aastra
Web UI. Configuration of priority alerting is on a global-basis only.
How Priority Alerting Works
When the IP phone detects an incoming call, the phone firmware inspects the
INVITE request in the IP packet for an "Alert-Info" header.
If it contains an "Alert-Info" header, the firmware strips out the URL and keyword
parameter and maps it to the appropriate Bellcore tone.
If there is no keyword parameter in the "Alert-Info" header, or the INVITE
message contains no "Alert-Info" header, then the IP phone firmware uses the
Bellcore standard ring tone.
Asterisk/Broadworks Servers
The ring tone keywords that can display in the "Alert-Info" header for an Asterisk
and Broadworks server are:
When the ring tone keywords appear in an "Alert-Info" header from an Asterisk or
Broadworks server, the IP phone maps the keywords to the default ring tone
patterns.
Asterisk/Broadworks Sesrver
Ring Tone Keywords
Bellcore-dr2
Bellcore-dr3
Bellcore-dr4
Bellcore-dr5