16 Exceptional procedures or unsuccessful outcome

22.0783GPPCustomised Applications for Mobile network Enhanced Logic (CAMEL)Release 17Service descriptionStage 1TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

16.1 Roaming in non-supporting networks

The HPLMN shall control handling of roaming, when a CAMEL subscriber attempts to register in a network not supporting CAMEL without relying on extra functionality in network entities not supporting CAMEL. The HPLMN can decide for each subscriber whether to allow roaming, or deny individual services (e.g. by applying ODB or denying location up-date).

If the HPLMN allows roaming, the OSSs are not supported for the roaming subscriber.

16.2 Call Set-up from a non-supporting interrogating PLMN

If the CAMEL feature is not supported in the IPLMN the following will happen:

– Mobile originating calls:

Not applicable.

– Mobile terminating calls:

Mobile terminating OSSs are not supported in the IPLMN if the HPLMN decides to allow the MT call attempt. The HPLMN may also decide to bar the incoming call attempt, or force the routeing interrogation to take place in the HPLMN.

16.3 Roaming in a VPLMN which supports a lower phase of CAMEL

If a CAMEL subscriber attempts to register in a VPLMN which supports CAMEL, the VPLMN shall indicate in the registration request to the HPLMN the phase of CAMEL which the VPLMN supports. If the VPLMN supports only a CAMEL phase which is lower than the one subscribed the HPLMN shall take such action (including denying the registration request or transferring to the VPLMN subscription information appropriate to the CAMEL phase supported in the VPLMN) as may be decided by the HPLMN operator. If a certain service requires a certain CAMEL phase (e.g. MO SMS requires at least CAMEL phase 3) and the VPLMN does not support that CAMEL phase, the HPLMN may decide to deny roaming or allow roaming without that particular CAMEL OSS.

16.4 Service attempt from a VPLMN which supports a lower phase of CAMEL

If the served subscriber requests a basic service (call, short message, GPRS attach, GPRS PDP context etc.) which requires the VPLMN to contact the CSE, the VPLMN shall indicate to the CSE which phase of CAMEL has been negotiated between the HPLMN and the VPLMN for this service. If the VPLMN supports a CAMEL phase which is lower than the one subscribed and the CSE determines that as a consequence a service which is provisioned for the subscriber will not operate correctly, the CSE shall take such action (including denying the call request or handling the call using only CAMEL capabilities supported in the VPLMN) as may be decided by the CSE operator.

16.5 Call setup from an IPLMN which supports a lower phase of CAMEL

The IPLMN shall indicate to the HPLMN which phases of CAMEL it supports. The HPLMN may decide to bar the incoming call attempt before contacting the CSE, or force the routeing interrogation to take place in the HPLMN. When the IPLMN contacts the CSE for instructions to handle an MT call, the IPLMN shall indicate to the CSE the phase of CAMEL which has been negotiated between the HPLMN and the IPLMN for this call. If the IPLMN supports a lower CAMEL phase than the one negotiated between the HPLMN and the IPLMN and the CSE determines that as a consequence a service which is provisioned for the subscriber will not operate correctly, the CSE shall take such action (including denying the call request or handling the call using only CAMEL capabilities negotiated between the HPLMN and the IPLMN) as may be decided by the CSE operator.

16.6 Roaming in a VPLMN with a partial implementation of CAMEL Phase 4

In principle, CAMEL based services require support of subscription information in the VPLMN and support for certain information flows between service logic (at the CSE) and the VPLMN. Subscription information are exchanged when a subscriber attempts to register in a VPLMN. Information flows are started when the VPLMN initiates contact to the CSE. Those procedures are de-coupled and happen at different points in time. If both procedures are supported sufficiently, services may be offered to a subscriber. The following chapter identifies requirements for a VPLMN to indicate its support of CAMEL Phase 4 features.

If a CAMEL subscriber attempts to register in a VPLMN which supports at least one CAMEL Phase 4 CSI or the enhanced CSE interrogation and control of subscription data, the VPLMN indicates in the registration request to the HPLMN the phase of CAMEL which the VPLMN supports (i.e. at least Phase 4). In addition, the VPLMN indicates which CAMEL Phase 4 CSIs or enhanced CSE interrogation and control of subscription it offers.

A VPLMN supports a CAMEL Phase 4 CSI if it is capable of initiating contact with the CSE due to that CSI using CAMEL Phase 4 procedures.

If the VPLMN does not support all CSIs or the enhanced CSE interrogation and control of subscription data of CAMEL phase 4, the HPLMN shall take such action (including denying the registration request or transferring to the VPLMN subscription information appropriate to the CAMEL Phase 4 CSI offered by the VPLMN) as may be decided by the HPLMN operator. If a certain service requires a certain CAMEL Phase 4 CSI (e.g. MT SMS handling) and the VPLMN does not support that CAMEL Phase 4 CSI, the HPLMN may decide to deny roaming or allow roaming without that particular CAMEL OSS.

If the VPLMN initiates contact with the CSE, or acknowledges a CSE initiated contact, the VPLMN indicates the CAMEL Phase 4 functionality offered to the CSE. This functionality should not contradict the capabilities the VPLMN has offered to the HPLMN at the registration time. Examples of functionality which can be offered to the CSE are:

Creating additional parties in a call;
Placing an individual call party on hold;
Mid Call procedure;
Inclusion of flexible tone injection;
etc.

16.7 Call setup attempt from an IPLMN which supports only a partial implementation of CAMEL Phase 4

If the IPLMN supports at least one CAMEL Phase 4 CSI, it indicates to the HPLMN (e.g. in the request for routeing information) which CAMEL Phase 4 CSIs it supports.

If the IPLMN does not support all CSIs of CAMEL phase 4, the HPLMN shall take such action (including barring the incoming call request or transferring to the IPLMN subscription information appropriate to the CAMEL Phase 4 CSI offered in the IPLMN) as may be decided by the HPLMN operator. If a certain service requires a specific CAMEL Phase 4 CSI and the IPLMN does not support that specific CAMEL Phase 4 CSI, the HPLMN may decide to bar the incoming call attempt, or force the routeing interrogation to take place in the HPLMN, or allow the MT call attempt without that particular CAMEL OSS.

The same principles for the IPLMN shall apply as defined in chapter 16.6 for the VPLMN.