When set to 0, IMSI is not required to be provisioned in the NCC transparent data and the call either be continued without CAMEL interaction or released when IMSI is not available from SIP Register.
When set to 1, IMSI is required to be provisioned in the NCC transparent data and when IMSI is not available from SIP Register the provisioned IMSI will be included in the CAP Initial DP message and call will be setup with CAMEL interaction.