User`s manual

MediaPack BRI Series
User's Manual 168 Document #: LTRT-83702
A.4 Configuring Supplementary Services
The MediaPack SIP gateway supports the following supplementary services:
 Call Hold / Retrieve; refer to Section 'Call Hold and Retrieve' on page 168.
 Transfer (Refer and Replaces); refer to Section 'Call Transfer' on page 169.
 Call Forward (3xx Redirect Responses); refer to Section 'Call Forward' on page 170.
 Call Waiting (182 Queued Response); refer to Section 'Call Waiting / Call Queued' on
page 171.
The above services are permanently active and cannot be disabled.
A.4.1 Call Hold and Retrieve
The MediaPack supports call hold and retrieve. You can place a call on hold, and then
create a new call without dropping the currently active call. After terminating the second
call, you can retrieve the first call and then continue the discussion.
Figure A-10: Call Hold
A.4.1.1 Call Hold from the ISDN Side
If the ISDN side initiates a call hold using the ISDN hold service, the SIP call is put on hold.
The MediaPack sends a SIP RE-INVITE to the peer to put the call on hold. If the ISDN user
retrieves the call after terminating the second call, the MediaPack uses a SIP RE-INVITE to
reactivate the call. The MediaPack uses the following attributes to place the call on hold:
 IP = 0.0.0.0
 a = inactive