IMG 1010 - SIP Call Hold

SIP Call Hold feature allows a User to generate a SUS message to put a call on hold or unplug a terminal from a socket and uses a RES message once the terminal is re-connected to a new socket and the T2 (User Initiated) or T6 (Network Initiated) timer has not expired. While the call is suspended, no audio media is passed end-to-end.

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The SIP Call Hold feature does not need to be configured. The only configuration needed is a user can decide to send either a CPG message or a SUSPEND and RESUME message when a re-invite message is received with c=0.0.0.0. Refer to the IMG 1010 - Interworking from ISUP to SIP topic for information on configuring this.