RELATING TO MESSAGING GATEWAYS

Abstract

The present disclosure provides a method of routing a short message to a user. According to the method, an SMSC sends a routing request to a HLR or HSS of the terminating user. The HLR or HSS has static provisioning settings for users and relays the request according to these settings. The HLR or HSS relays the request to the IP-SM-GW, which dynamically determines if the terminating user has attached to an IMS network and accordingly decides on onward routing of the message over circuit switched or IMS network elements. The present disclosure also provides a mobile network apparatus that is configured to perform the method.

Claims

1. A method of routing a short message to a user device, the method including the steps of: sending a short message routing request from an originating network element directly to an HLR or HSS of a terminating user; relaying the short message routing request by the HLR or HSS to a gateway; determining dynamically by the gateway if the terminating user is attached to an IMS network; and deciding, by the gateway, whether to perform onward routing of the short message over circuit switched domain or IMS network elements.

2. A method as claimed in claim 1, wherein the gateway is an IP-SM-GW.

3. A method as claimed in claim 1, wherein the short message routing request is originated by an SMSC.

4. A method as claimed in claim 1, wherein the terminating user is a voice-over-Long-Term-Evolution (VoLTE) user.

5. A method as claimed in claim 1, wherein the short message routing request is a MAP-SRI-FOR-SM request.

6. A method as claimed in claim 1, wherein the HLR or HSS has static provisioning settings for users and relays the short message routing request according to the settings.

7. A method as claimed in claim 1, wherein the determining step further comprises determining the status and location of the terminating user in the circuit switched domain.

8. A method as claimed in claim 7, further comprising sending the short message routing request to the HLR or HSS for retrieving the status and location of the user in the circuit switched domain.

9. A method as claimed in claim 1, wherein the gateway performs the determining step by: subscribing to a registration event package in a control function, and receiving from the control function a notification with a status of the terminating user and contact addresses of the terminating user.

10. A method as claimed in claim 9, wherein the control function is a CSCF assigned to the terminating user.

11. A method as claimed in claim 10, further comprising sending, by the gateway, a subscribe message to an I-CSCF to locate the S-CSCF to which the terminating user is assigned.

12. A method as claimed in claim 9, further comprising receiving, by the gateway in the notification, a user status and S-CSCF URI and contact addresses of the terminating user.

13. A method as claimed in claim 12, further comprising setting, by the gateway, an expiration time of the subscription to the event package as longer than an interval between individual delivery attempts.

14. A method as claimed in claim 1, further comprising, if the originating network element receives a notification that the terminating user is not present in either the IMS network or in a circuit switched domain, re-attempting sending the message at a subsequent time.

15. A method as claimed in claim 14, wherein the notification includes a delivery error-code.

16. A method as claimed in claim 14, wherein the originating network element is an SMSC.

17. A method as claimed in claim 16, further comprising the steps of: adding, by the originating network element, itself to a message waiting list in the HLR or HSS for the terminating user's MSISDN; notifying, by an S-CSCF, the gateway when the terminating user registers again in the IMS network; and notifying, by the gateway, the HLR or HSS.

18. A method as claimed in claim 17, wherein the notification to the HLR or HSS includes a MAP-READY-FOR-SM to the HLR, and further comprises the steps of: sending, by the HLR or HSS, an alert to the originating network element; and attempting, by the originating network after receiving the alert, a new delivery of the message.

19. A method as claimed in claim 17, further comprising switching, by the gateway, when the gateway receives a MAP-SEND-ROUTING-INFO-FOR-SM or a MAP-MT-FORWARD-SHORT-MESSAGE.

20. A mobile network apparatus comprising: an HLR or HSS; and a gateway, wherein the HLR or HSS is configured to relay a routing request to the gateway, wherein the gateway is configured to dynamically determine if the terminating user of the routing request has attached to an IMS network, and wherein the gateway is further configured to decide whether to perform onward routing of a message over a circuit switched domain or IMS network elements.

21. An apparatus as claimed in claim 20, wherein the gateway is an IP-SM-GW.

22. An apparatus as claimed in claim 21, wherein the HLR or HSS has static provisioning settings for users and is configured to relay the request according to the settings.

23. An apparatus as claimed in claim 22, wherein the gateway is further configured to determine status and location of the terminating user in the circuit switched domain, and to send the received routing request to the HLR or HSS for retrieving the status and location of the user in the circuit switched domain.

24. An apparatus as claimed in claim 23, wherein the gateway is further configured to subscribe to a registration event package in a control function, and to receive from the control function a notification including a status of the terminating user and contact addresses of the terminating user.

25. An apparatus as claimed in claim 24, wherein the gateway is further configured to send a subscribe message to an I-CSCF to locate the S-CSCF to which the terminating user is assigned, and to receive in the notification the status, an S-CSCF URI and contact addresses of the terminating user.

26. An apparatus as claimed in claim 25, wherein the gateway is further configured to set an expiry time of the subscription to the event package as longer than an interval between individual delivery attempts.

27. A non-transitory computer readable storage medium, the storage medium comprising instructions that are readable by a processor and cause the processor to: send a routing request from an originating network element directly to an HLR or HSS of a terminating user; cause the HLR or HSS to relay the request to a gateway; cause the gateway to determine dynamically whether the terminating user is attached to an IMS network; and cause the gateway to decide whether to perform onward routing of the message over circuit switched or IMS network elements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present disclosure will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings.

[0042] FIG. 1 shows a message sequence diagram illustrating an embodiment in which the terminating user is not present in the IMS domain.

[0043] FIGS. 2(a) and 2(b) together show a message sequence diagram in which a MT-FORWARD SM response is sent by the IP-SM-GW to the originating SMSC.

DETAILED DESCRIPTION OF THE DISCLOSURE

[0044] HLRs generally provide functionality to provision or configure a special Application Server Global Title in the MAP/SS7 network to which MAP-SEND-ROUTING-INFO-FOR-SM messages can be forwarded and where Mobile Terminated SMS traffic (MAP-MT-FORWARD-SHORT-MESSAGE) can be intercepted and processed before final delivery to the terminating user. This feature can be used for the IP-SM-GW function as well.

[0045] Instead of using the HLR or HSS as a switching point for making the choice whether delivery of a Mobile Terminated SMS should be done via the IMS or Circuit Switched network, the IP-SM-GW can do this function in a more efficient way.

[0046] When an SMSC wants to deliver a Mobile Terminated SMS to a VoLTE User, the SMSC sends a MAP-SEND-ROUTING-INFO-FOR-SM to the HLR/HSS of the terminating User. The HLR/HSS has a static provisioning of VoLTE Users and will relay the MAP-SEND-ROUTING-INFO-FOR-SM to the IP-SM-GW. The IP-SM-GW will send the MAP-SEND-ROUTING-INFO-FOR-SM to the HLR for retrieving the status and location of the user in the Circuit Switched network. In order to discover whether the VoLTE User is attached to the IMS-network, the IP-SM-GW will subscribe (SIP SUBSCRIBE) to the registration event package (event reg:) in the S-CSCF. The SIP SUBSCRIBE should be sent via the I-CSCF in order to find the S-CSCF to which the terminating user is assigned. The IP-SM-GW will receive a notification (NOTIFY) with the IMS user status, S-CSCF URI and contact addresses of the devices of the terminating user. This information can be used by the IP-SM-GW to deliver the Mobile Terminated SMS over SIP to the terminating user. The expiry-time of the subscription to the registration event package should be longer than the interval between individual delivery attempts of the sending SMSC in order to use the SMSC delivery attempt to have the IP-SM-GW initiating a new subscribe to the registration event package (event reg:) in the S-CSCF. This will prevent the IP-SM-GW to keep state about when a new subscriber needs to be initiated.

[0047] If delivery of the Mobile Terminated SMS fails due to the fact that the VoLTE user was not registered in the IMS and also not in the Circuit Switched network, the delivery error-code will be returned in the negative response to the SMSC and the SMS will be re-scheduled for a new delivery attempt. The message flows are illustrated in FIG. 1. The SMSC will also add itself to the Message Waiting Data (MWD) list in the HLR for the VoLTE user's MSISDN using the MAP-REPORT-SM-DELIVERY-STATUS. When the VoLTE user registers again in the IMS, the S-CSCF will notify the IP-SM-GW, which in turn will send a MAP-READY-FOR-SM to the HLR. Since the VoLTE user's MSISDN and SMSC are in the HLR MWD list, the HLR will send a MAP-ALERT-SERVICE-CENTRE to the SMSC. When receiving the MAP-ALERT-SERVICE-CENTRE for the VoLTE user, the SMSC will do a new delivery attempt of the Mobile Terminated SMS to the VoLTE User.

[0048] It will be appreciated by those of skill in the art that the disclosure uses existing HLR features to relay MAP-SEND-ROUTING-INFO-FOR-SM to an IP-SM-GW for delivery of Mobile Terminated SMS to IMS Users. There is no additional signaling introduced on the MAP/SS7-network due to the present disclosure. Also, no signaling will be required on the IMS-network when no Mobile Terminated SMS is due to be delivered by the SMSCs.

[0049] The present disclosure is not limited to the embodiments described but can be varied in construction and detail. For example, in another embodiment illustrated in FIGS. 2(a) and (b), the moment of switching is not done at the moment that the MAP-SEND-ROUTING-INFO-FOR-SM is received, but at the moment that the MAP-MT-FORWARD-SHORT-MESSAGE is received by the IP-SM-GW. In FIGS. 2(a) and 2(b), the message sequence shown is a MT-FORWARD SM response that is sent by the IP-SM-GW to the originating SMSC.

[0050] While the present disclosure has been described with reference to one or more exemplary embodiments, it will be understood by those skilled in the art that various changes can be made and equivalents can be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the disclosure without departing from the scope thereof. Therefore, it is intended that the present disclosure is not limited to the particular embodiment(s) disclosed as the best mode contemplated, but that the present disclosure will include all embodiments falling within the scope of the appended claims.