User`s manual

SIP User's Manual 8. Telephony Capabilities
Version 5.0 215 December 2006
8 Telephony Capabilities
8.1 Working with Supplementary Services
The MediaPack SIP FXS and FXO gateways support the following supplementary services:
 Call Hold / Retrieve; refer to Section 8.1.1 on page 215.
 Consultation / Alternate; refer to Section 8.1.2 on page 216.
 Transfer (Refer + Replaces); refer to Section 8.1.3 on page 216.
 Call Forward (3xx Redirect Responses); refer to Section 8.1.4 on page 217.
 Call Waiting (182 Queued Response); refer to Section 8.1.5 on page 217.
 Message Waiting Indication (MWI); refer to Section 8.1.6 on page 218.
To activate these supplementary services (Hold, Transfer, Forward, Waiting and MWI) on
the MediaPack gateway, enable each service’s corresponding parameter either from the
Web Interface or via the ini file. Note that all call participants must support the specific used
method.
Note: When working with application servers (such as BroadSoft’s
BroadWorks) in client server mode (the application server controls all
supplementary services and keypad features by itself), the gateway’s
supplementary services must be disabled.
8.1.1 Call Hold and Retrieve
8.1.1.1 Initiating Hold/Retrieve
 Active calls can be put on-hold by pressing the phone's hook-flash button.
 The party that initiates the hold is called the holding party; the other party is called the
held party.
 After a successful Hold, the holding party hears a Dial Tone.
 Call retrieve can be performed only by the holding party while the call is held and
active.
 The holding party performs the retrieve by pressing the hook-flash.
 After a successful retrieve, voice is connected again.
 Hold is performed by sending a REINVITE with the IP address 0.0.0.0 or ‘a=sendonly’
in the SDP according to the parameter ‘HoldFormat’.
8.1.1.2 Receiving Hold / Retrieve
 When an active call receives REINVITE message with either the IP address 0.0.0.0 or
the ‘inactive’ string in SDP, the gateway stops sending RTP and plays a local Held
Tone.
 When an active call receives REINVITE message with ‘sendonly’ string in SDP, the
gateway stops sending RTP and listens to the remote party. In this mode, it is
expected that on-hold music (or any other hold tone) is to be played (over IP) by the
remote party.