Matrix PRASAR UCS - Page 606

Matrix PRASAR UCS System Manual 597
How it works
• An Standard SIP Phone is registered as a SIP Extension, with the extension number 3301.
• As the user of extension 3301 wants to monitor the trunk SIP - 01, BLF subscription is enabled on
extension 3301 and SIP - 01 is assigned to the BLF key on the SIP phone.
• Extension 3301 makes an outgoing call to an external number 2630555. The BLF key will indicate the
current call state of the SIP - 01 Trunk as “Trying” according to the LED indication supported by the SIP
phone for this call state.
If the SIP phone supports text message display for call states, each call state will be displayed on the
phone.
• When the external party answers the call, the call between the SIP - 01 and SIP Extension 3301 gets
matured. The BLF key will indicate the current call state of the SIP Trunk as “Confirmed” according to the
LED indication supported by the SIP phone for this call state.
• When the SIP Extension 3301 disconnects the call, the PRASAR UCS will disconnect the call of external
number and the BLF key will display the call state of the SIP as “Terminated” according to the LED
indication supported by the SIP phone for this call state.
Similarly, the BLF key configured on the SIP Extension 3301 will display the call states of the SIP - 01 trunk
for incoming calls from external numbers.
Since multiple calls can be made through a single trunk, the BLF key will indicate the status of the first call
detected by the system. When the first call is terminated, the status of the second call (if ongoing) will be
indicated. Similarly the status of all subsequent calls will indicated after the previous call is terminated.
How to configure
To provide BLF to SIP extension users, you must do the following:
• Enable Busy Lamp Field Subscription on the SIP Extensions you want to provide this feature. For
instructions, see “Configuring SIP Extension using Jeeves” under “Configuring SIP Extensions”.
• Assign a BLF Key for the trunk to be monitored on the SIP Phones registered as extensions. For
instructions refer to the manufacturer’s documentation (Installation Guide/User Guide) for the respective
SIP Phones.
• To monitor the SIP trunks, configure the BLF Key as per the table given below:
Trunk User ID part in SUBSCRIBE Remarks
SIP SIPxx
Here, xx should be a valid SIP Trunk number, that is, from
01 to 99.