Delayed Media


The CSP supports delayed media to allow interworking with third party call control applications (3PCC).


Delayed media is implemented for inbound calls. That is, the CSP can accept a delayed media call but does not generate one.

The CSP accepts INVITE messages with SDP or without SDP or with held SDP.

The CSP accepts SDP in the positive ACK message.

Delayed media is not supported for bearer-free calls. It is supported for bearer calls only.


Connect instructing coupling and connection mode is not supported. In delayed media, the destination IP address is not known at the time of coupling, therefore the CSP cannot outseize an IPN-2 channel without the destination IP address and at the same time set the connection mode. The call will purge with reason 0x1A in this scenario.