Inter Operator Identifier (IOI)

Inter Operator Identifier (IOI) is a globally unique identifier to share between operator networks, service providers, and content providers, to correlate billing information generated within the IMS (IP Multimedia Subsystem).

The Inter-Operator-Identifier AVP holds the identification of the network neighbors (originating and terminating) as exchanged via SIP signalling.

The Originating-IOI AVP holds the Inter Operator Identifier (IOI) for the originating network as generated by the IMS network element which takes responsibility for populating this parameter in a SIP request.

The Terminating-IOI AVP holds the Inter Operator Identifier (IOI) for the terminating network as generated by the IMS network element which takes responsibility for populating this parameter in a SIP response.

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