SIP-SIPI Interworking Call Flows
When configured for SIP-SIP-I interworking, the SBC inserts and removes ISUP signaling information into SIP signaling messages as MIME bodies. You can also configure manipulation and/or translation rules to refine your interworking. The diagrams below present the order in which the SBC processes the relevant configuration objects, resulting in incremental changes. You must configure interworking manipulation ensuring that the changes caused by the latter processing are based on the results of preceding processing.
The diagram below shows a call initiated by a SIP endstation. The SBC interworks the call to SIP-I using your configuration and passes the call to the media gateway for SIPI to ISUP interworking. The SBC inserts the IAM as an ISUP MIME body part in the INVITE. The SBC also removes ACM presented by the SIP-I network from the 180 Ringing message.