7.2.123 Originating-IOI AVP

32.2993GPPCharging managementDiameter charging applicationsRelease 17Telecommunication managementTS

The Originating-IOI AVP (AVP code 839) is of type UTF8String (alphanumeric string) and 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 as described in RFC 7315 [404] and TS 24.229 [202]. The Originating IOI contains the following values:

Type 1 IOI

– IOI of the visited network where the P-CSCF is located for SIP requests directed to the S-CSCF when initiated by the served user

– IOI of the home network where the S-CSCF is located for SIP requests directed to the TRF in the visited network when "VPLMN routing" is applied in a Roaming Architecture for Voice over IMS with Local breakout.

– IOI of the home network where the S-CSCF is located for SIP requests directed to the visited network P-CSCF when terminated at the served user..

Type 2 IOI

– IOI of the home network of the originating end user where the S-CSCF is located in case a session is initiated from the IMS. In case of redirection by the S-CSCF, Originating-IOI AVP indicates the terminating party’s network operator from which the session is redirected.

– IOI of the visited network when "VPLMN routing" is applied in a Roaming Architecture for Voice over IMS with Local breakout.

– IOI of the originating network where the MGCF is located in case a session is initiated from the PSTN toward the IMS.

Type 3 IOI

– IOI of the home network (originating side or terminating side) where the S-CSCF is located when forwarding a SIP request as described in TS 24.229 [202] to an AS (proxy, terminating UA or redirect server or B2BUA).

– IOI of the service provider network where the AS is located when an AS (originating UA or B2BUA) initiates a SIP request as described in TS 24.229 [202].

For further details on the Type 1, Type 2 and Type 3 IOIs, please refer to TS 32.240 [1].