WO2010072242A1

WO2010072242A1 - Service control based on subscriber identity

Info

Publication number: WO2010072242A1
Application number: PCT/EP2008/011076
Authority: WO
Inventors: Juha Kallio
Original assignee: Nokia Siemens Networks Oy
Priority date: 2008-12-23
Filing date: 2008-12-23
Publication date: 2010-07-01

Abstract

A method, apparatus, and computer program product, wherein a subscriber identity received in an attach request from a mobile terminal is compared with at least one predetermined range of identities, and a service capability is selected in response to the result comparison. The selected service capability is then transmitted in an attach response to the terminal device.

Description

Service Control Based on Subscriber Identity

FIELD OF THE INVENTION

The present invention relates to a method, an apparatus, and a computer program product for controlling selection of a service capability in a network environment involving heterogeneous access networks, such as for example Long Term Evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) Radio Access Network (UTAN) or Enhanced Packet System (EPS).

BACKGROUND OF THE INVENTION

To enhance the capability of mobile communication systems to cope with the rapid growth in Internet Protocol (IP) data traffic, PS technology utilised within third generation (3G) mobile networks requires further enhancement. A continued evolution and optimisation of the system concept is necessary in order to maintain a competitive edge in terms of both performance and cost. Important improvements of LTE comprise reduced latency, higher user data rates, improved system capacity and coverage, and reduced overall operator costs.

Additionally, it is expected that IP based 3GPP (3^rd Generation Partnership Project) services will be provided through various access technologies. A mechanism to support seamless mobility between heterogeneous access networks is a useful feature for future network evolution. LTE or EPS is a packet switched (PS) only radio access and core architecture that has been defined in the 3GPP specification TR 23.882. The EPS contains both an Evolved Packet Core (EPC) as well as an Evolved UTRAN (eUTRAN) or LTE radio access.

A driver for new radio access technology is much higher end user bit rates compared to conventional 3GPP defined PS only radio access technologies (e.g. High Speed Packet Access (HSPA)) as well as flexible capability for use of different radio frequencies than in currently available radio technology. Additionally one notable difference to other 3GPP defined technologies is lack of Circuit Switched (CS) capability in order to fully optimize radio for PS traffic. Whereas LTE is PS only technology there has still been a need to ensure possibility to re-use existing CS core networks (CNs) as voice service machinery even when a terminal is LTE aware. A reason for this has been the available CS core network architecture and the inefficiency of simultaneously deploying both IP Multimedia System (IMS) and new PS only access and core architectures.

Earlier it was assumed that IMS deployment was always required when LTE is deployed in order to enable operator voice service (such as Voice over IP

(VoIP)) but this has changed. IMS-independency has been achieved by a so called CS fallback procedure has been defined as a result of CS over evolved

PS work item of 3GPP Release 8. This procedure is described at high level in alternative 3 ("Page in eUTRAN, Call in GSM/WCDMA") in 3GPP specification TR 23.879. This mechanism to uses a Gs-like interface between EPC (i.e. mobility management entity (MME)) and CS CN (e.g. Mobile Switching Center

(MSC) or MSC Server) in order to page and move subscribers to a legacy RAN for call completion. This mechanism fulfills the requirement that calls are served by a CS CN while subscriber's data service is maintained by re-use of PS-PS relocation procedure between EPS and legacy PS networks. This interface has been named as SGs interface in 3GPP specification TS 23.272 which defines

CS fallback for EPS in detail.

A Gs-interface has been typically deployed in Global System for Mobile Com- munications (GSM) networks between a second generation (2G) base station controller (BSC) and an MSC or MSC server network element in so called Network Mode Operation 1 (NMO1 ), which is used to execute paging coordination when a subscriber is simultaneously attached to PS and CS domains. It should also be noted in this context that typically the Gs-interface has not been used in 3G access networks because the radio network controller (RNC) has been able to do paging co-ordination by itself.

In case a mobile network operators wants to provide voice service (such as VoIP) using EPS, use of IMS and related Session Initiation Protocol (SIP) based technologies has been proposed. This solution requires that the network supports a so called Single Radio Voice Call Continuity (SR-VCC) functionality in order to handover an ongoing VoIP session from EPS to CS call in a legacy CS core network. This solution involves joint interworking between IMS, EPS as well as the existing CS core network in order to successfully execute the SR- VCC procedure which as described in more detail in the 3GPP specification TS 23.216.

Currently both the SR-VCC and call session control function (CSCF) features expect that a specific capability indication is exchanged between the EPS and the LTE capable terminal when terminal attaches to the EPS. This indication can be analyzed at the terminal side and used as a basis for future decisions as to whether SR-VCC capability exists in available LTE and CS networks and whether the networks support CS Fallback for EPS.

A problem which results from the above procedure is that in practical deployment scenarios of EPS technology, network operators need to be able to control use of those features in more granular manner than just by indicating these capabilities to all LTE terminals without any exceptions.

SUMMARY

In an embodiment an apparatus comprises:

• comparing means for comparing a subscriber identity received in an attach request from a mobile terminal with at least one predetermined range of identities;

• selecting means for selecting a service capability in response to said comparison means; and

• transmitting means for transmitting said selected service capability in an attach response to said terminal device.

In an embodiment a method comprises:

• comparing a subscriber identity received in an attach request from a mobile terminal with at least one predetermined range of identities;

• selecting a service capability in response to said comparing step; and

• transmitting said selected service capability in an attach response to said terminal device. Accordingly, a flexible capability advertisement is provided, where the subscriber identity is analysed at the network side during network attachment and based on this information the network is enabled to decide which capabilities are advertised to which subscriber (terminal) attaching to network.

A terminal roaming in a network can thus be differentiated with regard to services or mechanisms available for different subscribers coming from different networks into same visited network. Network operators can configure the network to use agreed services or mechanism based on ranges of subscriber identities.

The service capability may be selected based on a range of identities to which the received subscriber identity belongs. This can be achieved by simply providing at the network side a relation between preconfigured range(s) of subscriber identities and allocated service capabilities.

A predetermined default procedure may be initiated if the comparison indicates that the received subscriber identity does not belong to the at least one range of identities.

As an example, the service capability may be selected from a group of capabilities comprising a single radio continuity functionality, a circuit switched fallback functionality, and a no service functionality (indicating that the concerned service is not available at all). More specifically, the service capability may be for example a voice service capability.

Further advantageous modifications are defined in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, an embodiment will be described in greater detail with reference to the accompanying drawings, in which:

Fig. 1 shows a schematic block diagram of a communication system with heterogeneous access networks, in which the present invention can be implemented; Fig. 2 shows a signalling and processing diagram of a CS fallback procedure;

Fig. 3 shows a flow diagram of a voice service control procedure according to an embodiment;

Fig. 4 shows a schematic block diagram of an MME device according to an embodiment; and

Fig. 5 shows a schematic block diagram of an embodiment based on a software implementation.

DESCRIPTION OF THE EMBODIMENT

Embodiments will now be described based on an EPS architecture. The proposed service control based on capability advertisement can be applied in any suitable network element responsible for managing network access or attachment.

FIG. 1 depicts an EPS based network architecture where voice services can be realized by reuse of CS infrastructure. The terminal or user equipment (UE) can be connected via an U(x) interface to an eUTRAN 24 with at least one enhanced Node B 240. Additionally or alternatively, depending on the capability of the UE 100, it can be connected via the U(x) interface to a CS access network 22 (e.g. UTRAN and base station subsystem (BSS)) which provides access via an A/lu interface to a CS core network 40 having a media gateway (MGW) 400 and at least one MSC server 420.

The eUTRAN 24 is connected via an S1 interface to an EPC 30 with an MME 300. The concepts from 2G/3G of the Gs interface are used between the MSC server 420 of the CS core network 40 and a serving GPRS (General Packet Radio Services) Support Node (SGSN, not shown). Thus, for a location update procedure and for paging messages a SGs ("Gs like") interface 10 can be provided between the MME 300 and the MSC server 420, and EPS mobility management can be used. The MME 300 is further connected to a home subscriber server (HSS) 500 in which subscriber data is stored and via an S11 interface to a serving or packet data network (PDN) gateway 600. Both MSC server 420 and serving/PDN gateway 600 (via SGi interface) provide access to an IMS 50. A CS fallback procedure in EPS enables the provisioning of voice and other CS- domain services (e.g. CS video or SMS (Short Message service) or LCS (location service) or USSD (Unstructured Supplementary Service Data)) by reuse of the CS infrastructure when the UE 100 is served by the eUTRAN 24. A CS fallback enabled terminal, connected to eUTRAN may thus use the CS access network 22 to establish one or more CS-domain services. This function is available in case eUTRAN coverage is overlapped by CS access network coverage. Thus, CS fallback and IMS-based services can co-exist in the same operator's network.

If the UE 100 is configured to use IMS voice services, SMS over IP etc. it may, if registered to the IMS 50, initiate voice calls or send SMS etc. over the IMS 50, even if it is EPS attached e.g. with an International Mobile Subscriber Identity (IMSI). The home operator may be able to activate/deactivate the configuration of the UE 100 to use IMS voice services by means of device management in order to allow alignment with home network support of IMS voice services.

Fig. 2 shows a signalling and processing diagram of a CS fallback procedure which may be initiated for example when the UE 100 is IMS registered and EPS/IMSI attached but can not initiate an IMS voice session or SMS (because e.g. IMS voice services are not supported by the serving IP Connectivity Access Network (IP-CAN) or by the UE 100). The CS fallback can be applied for voice calls, SMS₁ and other services.

In step 1 of Fig. 2, the UE 100 initiates the attach procedure by transmission of an attach request (parameters may be provided as specified in 3GPP specification TS 23.401 including the attach type) to the MME 300. The attach type indicates that the UE 100 requests a combined EPS/IMSI attach and informs the network that the UE 100 is capable and configured to use CS fallback. In step 2, the EPS attach procedure is performed e.g. as specified in 3GPP specification TS 23.401. Then, in step 3, a visitor location register (VLR) provided at the MSC server 420 may be updated if the attach request includes an attach type indicating that the UE 100 requests a combined EPS/IMSI attach. The MME 300 starts the location update procedure towards the MSC server 400 upon receipt of a first insert subscriber data message from the HSS 500 in step 2. This operation marks the UE 100 as EPS-attached in the VLR. In step 4 the MME 300 sends a location update request to the VLR at the MSC server 400. In step 5, the VLR creates an association with the MME 300 by storing an MME address received in the location update request. In step 6, the VLR performs a location updating procedure in the CS domain, and responds in step 7 with a location update accept message to the MME 300. Finally, in step 8, the MME 300 sends an attach accept message to the UE 100 to confirm attachment to the CS domain.

According to various embodiment described hereinafter, service control based on subscriber identity (e.g. IMSI) can be provided to all terminals. In the example of the following embodiments, the IMSI of an LTE capable subscriber is analysed in the MME 300 and based on this information it is decided which capabilities are advertised from the network to which subscriber (i.e. terminal) attaching to the network.

Fig. 3 shows a flow diagram of a voice service control procedure according to an embodiment, which may be executed at the MME 300.

In step S101 , an IMSI received from a terminal (e.g. UE 100) is analyzed or extracted. Then, in step S102 it is compare to p re-configured IMSI ranges to which different capabilities have been allocated. In step S103 it is then checked if the received IMSI falls within or belongs to one of the pre-configured IMSI ranges. In case it is determined in step S103 that the received IMSI belongs to a pre-configured IMSI range, then voice service related capabilities are selected in step S104. The selected capabilities are then advertised in step S105 as a result to the terminal during the LTE attach procedure. The selected capabilities may comprise the above SR-VCC capability and/or the above CS fallback capability and/or a no LTE voice capability indicating that no LTE voice service is available at all.

If it is determined in step S103 that the received IMSI for some reason does not belong to any known and pre-configured IMSI range related to this selection procedure, then some default behaviour (e.g. error message or suggestion or the like) is initiated in step S106 e.g. by the MME 300. This default behaviour as well as the known IMSI ranges can be configured by the network operator.

This service control procedure can be used to ensure that agreement between operators can be met in the network by indicating correct capabilities to correct subscribers that can be both own and in-bound roaming subscribers. Fig. 4 shows a schematic block diagram of an MME device (e.g. the MME 300 of Fig. 1 ) according to an embodiment.

The MME 300 comprises a transceiver functionality or unit (TRX) 302 for transmitting and receiving information to/from the network. Received information is supplied to a subscriber identity detection functionality or unit (SID) 304 which extracts the subscriber identity (e.g. IMSI) from a received message (e.g. attach request) and supplies it to a comparator functionality or unit (C) 306. The comparator unit 306 compares the received subscriber identity with pre- configured identity ranges stored in a look-up table (LUT) 307 which may be provided in a programmable memory device. The comparison result (e.g. identified identity range or no range at all) is forwarded to a capability selection functionality or unit (CS) 308 which selects capabilities allocated to the identity range to which the received subscriber identity belonged, and advertises the selected capabilities via the transceiver unit 302. If no matching range has been identified by the comparator unit 306, a default procedure may be initiated by the capability selection unit 308.

Fig. 5 shows a schematic block diagram of an alternative software-based embodiment of the proposed service control functionalities. The required functionalities can be implemented for example in the MME 300 or any similar network element which receives an attach request and/or performs mobility management control. This embodiment comprises a processing unit (PU) 310, which may be any processor or computer device with a control unit which performs control based on software routines of a control program stored in a memory (MEM) 312. Program code instructions are fetched from the memory 312 and are loaded to the control unit of the processing unit 310 in order to perform the processing steps of the above functionalities described in connection with the block diagram of Figs. 4 or the flow diagram of Fig. 3. These processing steps may be performed on the basis of input data Dl and may generate output data DO, wherein the input data Dl may correspond to a received message (e.g. attach request) with a subscriber identity (e.g. IMSI). The output data DO may correspond to at least one signalled capability.

The above embodiments can be implemented in hardware by a discrete analog or digital circuit, signal processor, or a chip or chip set (e.g. an ASIC (Application Specific Integrated Circuit)), or in software either in an ASIP (Application Specific Integrated Processor), a DSP (Digital Signal Processor), or any other processor or computer device. In summary, a method, apparatus, and computer program product have been described, wherein a subscriber identity received in an attach request from a mobile terminal is compared with at least one predetermined range of identities, and a service capability is selected in response to the result comparison. The selected service capability is then transmitted in an attach response to the terminal device.

It is noted that the present invention can be implemented or used in any communication or network system where different service capabilities are used e.g. depending on the access technology. More specifically, the present invention can be applied to radio access systems like e.g. WiMAX as currently standardized in 3GPP for WCDMA (Wideband Code Division Multiple Access), Wireless Local Area Networks (WLANs), as well as 3GPP E-UTRAN such as LTE (Long Term Evolution) or 3.9G. The proposed capability selection is not restricted to a voice service capability, but may as well be based on any network service which can involve or require different capabilities, for example based on a type of network technology.

As already mentioned, the embodiments can be realized in hardware, software, or a combination of hardware and software. A typical combination of hardware and software can be a processing system with an application that, when being loaded and executed, controls the processing system such that it carries out the methods described herein. The embodiment also can be embedded in an application product, which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a processing system is able to carry out these methods.

The terms "computer program," "software," "application," variants and/or combinations thereof, in the present context, mean any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form. For example, an application can include, but is not limited to, a subroutine, a function, a procedure, an object method, an object implementation, an executable application, an applet, a servlet, a source code, an object code, a shared library/dynamic load library and/or other sequence of instructions designed for execution on a processing system. The terms "a" and "an," as used herein, are defined as one or more than one. The term "plurality," as used herein, is defined as two or more than two. The term "another," as used herein, is defined as at least a second or more. The terms "including" and/or "having," as used herein, are defined as comprising (e.g., open language). Accordingly, the above predetermined embodiments may vary within the scope of the attached claims.

Claims

1. An apparatus comprising:

5 comparing means (306) for comparing a subscriber identity received in an attach request from a mobile terminal with at least one predetermined range of identities;

selecting means (308) for selecting a service capability in response too said comparison means (306); and

transmitting means (302) for transmitting said selected service capability in an attach response to said terminal device. s

2. The apparatus according to claim 1 , wherein said selecting means (308) is configured to select said service capability based on a range of identities to which said received subscriber identity belongs.

3. The apparatus according to claim 1 or 2, wherein said selecting meanso (308) is configured to initiate a predetermined default procedure if an output of said comparing means indicates that said received subscriber identity does not belong to said at least one range of identities.

4. The apparatus according to any one of the preceding claims, wherein5 said selecting means (308) is configured to select said service capability from a group of capabilities comprising a single radio continuity functionality, a circuit switched fallback functionality, and a no service functionality. 0

5. The apparatus according to claim 1 , wherein said service capability is a voice service capability.

6. A mobile management network element comprising an apparatus according to claim 1. 5

7. A chip device comprising an apparatus according to claim 1.

8. A method comprising: comparing a subscriber identity received in an attach request from a mobile terminal with at least one predetermined range of identities;

selecting a service capability in response to said comparing step; and

transmitting said selected service capability in an attach response to said terminal device.

9. The method according to claim 8, further comprising selecting said service capability based on a range of identities to which said received subscriber identity belongs.

10. The method according to claim 8 or 9, further comprising initiating a predetermined default procedure if said comparing step indicates that said received subscriber identity does not belong to said at least one range of identities.

11. The method according to any one of claims 8 to 10, further comprising selecting said service capability from a group of capabilities comprising a single radio continuity functionality, a circuit switched fallback functionality, and a no service functionality.

12. The method according to claim 8, wherein said service capability is a voice service capability.

13. A computer program product comprising code means for producing the steps of method claim 8 when run on a computer device.