6.3 Transport-level interworking: Successful encapsulated Short Message origination procedure with MSISDN

23.2043GPPRelease 17Stage 2Support of Short Message Service (SMS) over generic 3GPP Internet Protocol (IP) accessTS

Figure 6.3: Successful encapsulated Short Message origination procedure

1) The UE registers to S-CSCF according the IMS registration procedure. Note that I-CSCF and P-CSCF are not shown in this figure.

2) UE submits the encapsulated Short Message (SMS-SUBMIT, SC Address) to the S-CSCF using an appropriate SIP method.

3) S-CSCF forwards the encapsulated Short Message (SMS- SUBMIT, SC Address) to IP-SM-GW (AS) based on stored iFC.

4) IP-SM-GW (AS) acknowledges the SIP message.

5) SIP message acknowledge is forwarded by S-CSCF to UE.

6) The IP-SM-GW performs service authorization based on the stored subscriber data as described in the clause 6.1. The IP‑SM‑GW shall check whether the subscriber is authorised to use the short message service (e.g. Operator Determined Barring settings), similar to the authorization performed by MSC/SGSN in case the Short Message is delivered via CS or PS domain. In addition, the IP-SM-GW shall also check whether the user is authorised to use the encapsulated Short Message delivery via IMS. If the result of service authorization is negative, the IP-SM-GW shall not forward the message, and shall return the appropriate error information to the UE in a failure report. Otherwise, the IP-SM-GW (AS) extracts the Short Message (SMS- SUBMIT) and forwards it towards the SMS-SC (SC Address) via the SMS-IWMSC using standard MAP or Diameter based (SGd/Gdd) signalling (as described in TS 23.040 [2]).

7) The SMS-IWMSC forwards the Short Message (SMS-SUBMIT) to the SMS-SC (see TS 23.040 [2]).

8) SMS-SC sends a Submit report (SMS-SUBMIT‑REPORT) to SMS-IWMSC (see TS 23.040 [2]).

9) SMS-IWMSC sends the Submit report to IP-SM-GW (AS) (see TS 23.040 [2]).

10) IP-SM-GW (AS) sends the Submit report to S-CSCF, encapsulated in an appropriate SIP request.

11) The S-CSCF sends the Submit report to the UE.

12) The UE acknowledges the SIP request.

13) The S-CSCF forwards the acknowledgement of the SIP request to IP-SM-GW (AS).