H.1 Interworking SIP to ISUP

29.1633GPPInterworking between the IP Multimedia (IM) Core Network (CN) subsystem and Circuit Switched (CS) networksTS

The "oli" URI parameter received within tel URI or the userinfo part of SIP URI with user="phone" (as defined in clause 7.2A.12 of 3GPP TS 24.229 [9]) received in a P-Asserted-Identity header in the initial INVITE request shall be used to set the ISUP IAM OLI parameter. In case the P-Asserted-Identity URI "oli" parameter is absent then the ISUP IAM OLI parameter shall be omitted.