Aastra 9000i Series Administrator's Manual page 435

Asterisk BLF Configuration
You can enable the BLF feature on Asterisk to enable monitoring for specific extensions. BLF
on Asterisk is possible through the "hint" extension parameter.
Add the following in the Asterisk extensions.conf file for each target extension being monitored.
For example:
exten -> 9995551212,hint,SIP/9995551212
Add the following in the Asterisk sip.conf file for each subscriber if it is not defined already.
For example:
[9995551212]
Subscribecontext=sip
BroadSoft BLF Configuration
You can enable the BLF feature on BroadSoft BroadWorks Rel 13 or higher through the
BroadWorks Web Portal. Each user must have the Busy Lamp Field service enabled for their
user. The user must add each desired extension to the "Monitored Users List" on the Busy Lamp
Field service page and also enter in a list name for the monitored users BLF list on the same
page.
Changes to the "Monitored Users List" are dynamic and the Aastra IP phones are automatically
updated without requiring a restart.
Reference
For sample BLF configurations, see Appendix D, "Sample BLF Softkey Settings."
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