Roaming Subscriber

TECHNICAL FIELD

The present invention relates to the technical field of mobile communication, more specifically, to a technology of controlling the separated charging of a later forwarded call of a roaming subscriber. BACKGROUD OF THE INVENTION

In May and June 2012, European Parliament and representatives of the Council and the European Commission have reached a preliminary deal on new EU (European Union) Roaming rules that will fundamentally change the market for international roaming to benefit holidaymakers and business users: From 1 July 2014, customers would have the option to sign up for a cheaper mobile roaming contract, separate from their contract for national mobile services, while keeping the same phone number. Consumers will therefore be able to easily compare roaming offers and benefit from lower prices. The European commission proposes more competition, and more choice and lower prices for the end user roaming abroad.

Currently, the mobile roaming contract to end user is still defined by HMNO (Home Mobile Network Operator), the roaming tariff plan is closely bundled into the home tariff plan.

This current roaming charging solution doesn't support the new EU regulation requirement. As the new EU regulation requirement, the mobile roaming contract shall be separated from their contract for national mobile services, while keeping the same phone number, the mobile roaming service and payment contract can be offered from the different alternative roaming providers (ARP). To decouple the roaming service from the home service provider, one approach is to have

ARP to provide roaming service and the home network operator to provide the national service. The EU regulated roaming call is charged in ARP's charging system, the non-EU regulated roaming call is charged in HMNO's charging system. Currently, the new EU roaming regulation has some condition to apply, e.g. an EU subscriber is roaming in another EU country, and called party 's number is also an EU number etc. If the EU subscriber stays at the home country, or is roaming in non-EU country, these kinds of call will not be applicable to the new EU roaming regulation.

How to support the ODiN (Optimal Diversion to Number) service for EU roaming subscribers will be a great challenge for most operators to fully meet the new EU regulation structure, when the EU subscriber is roaming in EU country, how to handle and change the later forwarded call when the subscriber cannot accept the call since he/she is busy/unreachable etc. According to the new EU roaming regulation, it will be easier to implement one roaming call either in home charging system or ARP charging system. But when a call is forwarded to another number and the later forwarded call is happened in the roaming network, e.g. FDTVM (Free Divert to Voice Mail), to avoid the expensive charge for the roaming forwarded call, the later forwarded call from VMSC (Visited Mobile Switching Center) in roaming network will be released; the forwarded number will be connected via GMSC (Gateway Mobile Switching Center) in home network. Since the initial call is charged in ARP OCS (Online Charging System), but when the call is forwarded to another number by home network, the later forwarded call will not be applicable to the EU roaming regulation. This will cause the difficulty to split the subscriber's EU roaming call in home OCS or in ARP OCS. Further, this will bring the challenge how to apply the new EU roaming regulation to the traditional IN (Intelligent Network) roaming service.

SUMMARY OF THE INVENTION The objective of the present invention is to provide a method for controlling the separated charging of a later forwarded call of a roaming subscriber, and an apparatus and systems thereof.

According to one aspect of the present invention, a method for a call control apparatus to control the separated charging of a later forwarded call of a roaming subscriber is provided, wherein the roaming subscriber has a homing mobile service provided by a home network and a mobile roaming service provided by an alternative roaming provider, wherein the method comprises: a. requesting OCS of the alternative roaming provider to charge data services of the roaming subscriber when the roaming subscriber has an incoming call and is located in a service area of the alternative roaming provider; b. determining OCS corresponding to the later forwarded call when the incoming call is about to be call forwarded; c. requesting OCS of the home network to charge the later forwarded call when the later forwarded call is forwarded by the home network.

According to another aspect of the present invention, a call control apparatus for controlling the separated charging of a later forwarded call of a roaming subscriber is provided, wherein the roaming subscriber has a homing mobile service provided by a home network and a mobile roaming service provided by an alternative roaming provider, wherein the call control apparatus comprises: a first charging request module configured to request OCS of the alternative roaming provider to charge data services of the roaming subscriber when the roaming subscriber has an incoming call and is located in a service area of the alternative roaming provider; an OCS determining module configured to determine OCS corresponding to the later forwarded call when the incoming call is about to be call forwarded; a second charging request module configured to request OCS of the home network to charge the later forwarded call when the later forwarded call is forwarded by the home network.

According to a further aspect of the present invention, a system for controlling the separated charging of a later forwarded call of a roaming subscriber is provided, wherein the roaming subscriber has a homing mobile service provided by a home network and a mobile roaming service provided by an alternative roaming provider, wherein the system comprises a call control apparatus for controlling the separated charging of the later forwarded call of the roaming subscriber and a VMSC in a roaming place of the roaming subscriber, wherein: the call control apparatus comprises: a first charging request module configured to request OCS of the alternative roaming provider to charge data services of the roaming subscriber when the roaming subscriber has an incoming call and is located in a service area of the alternative roaming provider; an OCS determining module configured to determine OCS corresponding to the later forwarded call when the incoming call is about to be call forwarded; a second charging request apparatus configured to request OCS of the home network to charge the later forwarded call when the later forwarded call is forwarded by the home network. The VMSC comprises: a forwarded-to-number determining module configured to determine a forwarded-to-number to which the incoming call is about to be forwarded when an incoming call to the roaming subscriber satisfies a trigger condition of call forwarding; a first forwarding sending module configured to send the forwarded-to-number to the call control apparatus.

According to a still further aspect of the present invention, a system for controlling the separated charging of a later forwarded call of a roaming subscriber is provided, wherein the roaming subscriber has a homing mobile service provided by a home network and a mobile roaming service provided by an alternative roaming provider, wherein the system comprises a call control apparatus for controlling the separated charging of the later forwarded call of the roaming subscriber, a GMSC of the home network, and a VMSC in a roaming place of the roaming subscriber, wherein: the call control apparatus comprises: a first charging request module configured to request OCS of the alternative roaming provider to charge data services of the roaming subscriber when the roaming subscriber has an incoming call and is located in a service area of the alternative roaming provider; a second forwarding receiving module configured to receive, from the GMSC, a forwarded-to-number of the later forwarded call to which the incoming call is about to be forwarded; an OCS determining module configured to determine OCS corresponding to the later forwarded call when the incoming call is about to be call forwarded; a second charging request apparatus configured to request OCS of the home network to charge the later forwarded call when the later forwarded call is forwarded by the home network.

The VMSC comprises: a forwarded-to-number determining module configured to determine a forwarded-to-number to which the incoming call is about to be forwarded when an incoming call to the roaming subscriber satisfies a trigger condition of call forwarding; a second forwarding sending module configured to send the forwarded-to-number of the later forwarded call to the GMSC; the GMSC comprises: a forwarding receiving module configured to receive the forwarded-to-number of the later forwarded call from the VMSC; a forwarding sending module configured to send the forwarded-to-number of the later forwarded call to the call control apparatus.

Compared with the prior art, the present invention enables a charging system of a home network to charge a later forwarded call of a subscriber when the subscriber is located in a serving area of ARP, its incoming call being call forwarded to a forwarded-to-number of the home network of the subscriber due to no answer and being un-reached, etc., so as to control the separated charging of the later forwarded call of the roaming subscriber.

DESCIPTION OF ACCOMPANIED DRAWINGS

Through reading the following detailed depiction on the non-limiting embodiments with reference to the accompanying drawings, the other features, objectives, and advantages of the present invention will become clearer.

Fig. 1 shows a flow chart of a method for controlling the separated charging of a later forwarded call of a roaming subscriber according to one aspect of the present invention; Fig. 2 shows a schematic diagram of a system for controlling the separated charging of a later forwarded call of a roaming subscriber according to one embodiment of the present invention;

Fig. 3 shows a schematic diagram of a system for controlling the separated charging of a later forwarded call of a roaming subscriber according to another embodiment of the present invention; Fig. 4 shows a schematic diagram of signal flow according to a first preferred embodiment of the system of Fig. 2;

Fig. 5 shows a schematic diagram of signal flow according to a second preferred embodiment of the system of Fig. 2;

Fig. 6 shows a schematic diagram of signal flow according to a third preferred embodiment of the system of Fig. 2;

Fig. 7 shows a schematic diagram of signal flow according to a fourth preferred embodiment of the system of Fig. 2;

Fig. 8 shows a schematic diagram of signal flow according to a fifth preferred embodiment of the system of Fig. 2; Fig. 9 shows a schematic diagram of signal flow according to a sixth preferred embodiment of the system of Fig. 2;

Fig. 10 shows a schematic diagram of signal flow according to a seventh preferred embodiment of the system of Fig. 3;

Fig. 11 shows a schematic diagram of signal flow according to an eighth preferred embodiment of the system of Fig. 3;

Fig. 12 shows a schematic diagram of a system for controlling the separated charging of a later forwarded call according to one embodiment of the present invention;

Fig. 13 shows a schematic diagram of a system for controlling the separated charging of a later forwarded call according to another embodiment of the present invention. Same or like reference numerals in the accompanying drawings indicate the same or corresponding components.

EMBODIMENTS OF THE INVENTION Hereinafter, the present invention will be further described in detail with reference to the accompanying drawings.

The present invention provides a solution of controlling the separated charging of a later forwarded call of a roaming subscriber, to fully comply with the new EU roaming regulation and still keep the existing roaming service availability. The present invention fully enables the operator to support the new EU regulation and fulfills most of EU-commission's expectation, especially timeframe 2014, and still keeps the existing roaming service availability for end user. The present invention provides a call control apparatus for controlling the separated charging of a later forwarded call of a roaming subscriber. The call control apparatus may be an independent apparatus or integrated into OCS of current HPLMN (home public land mobile network), so as to support the new EU roaming regulation III on the ODiN/FDTVM call. When a subscriber is in a home location, the call control apparatus requests the charging system of the home network to charge the data traffic of the subscriber; when the subscriber is in a serving area of ARP, the call control apparatus requests the charging system of the ARP to charge the data traffics of the subscriber.

In order to conform to the new EU roaming rule, the DSP will separate the roaming service contract from a domestic mobile service contract so as to provide ARP.

- ARP OCS maintains subscriber balance for roaming services, handles charging request, and performs credit authentication and charging control for roaming services; these services are separated to the ARP based on the new EU roaming regulations;

- DSP OCS maintains the subscriber balance and performs charging control for domestic services and those non-EU regulated roaming services.

The call control apparatus receives a charging request from a network element, performs new EU roaming rules, and determines whether the charging request should be sent to the ARP OCS or the charging request should be sent to the DSP OCS.

The interface from the call control apparatus to the ARP OCS may be a Diameter online charging interface or a CAP interface; the interface from the call control apparatus to the DSP OCS may be a Diameter online charging interface or a CAP/ CS1 interface.

Besides, when an EU subscriber is roaming in a non-EU country, the EU roaming regulation III does not apply any more, and the MTC incoming calls and later forwarded calls are all charged by the DSP OCS.

For the non-EU subscriber roams in an EU or a non-EU country, the EU roaming regulation III does not apply. The MTC incoming calls and the later forwarded calls are all charged by the DSP OCS. For the convenience of illustration, in this context, such an example is often taken: subscriber A calls roaming subscriber B, which call is forwarded to a number C. In other words, subscriber A is a calling party, subscriber B is a called party, and number C is a call forwarded-to-number. Herein, the call of subscriber A —subscriber B is called an initial incoming call or an initial call; the forwarded call of subscriber A ^→ forwarded-to-number C is called a later forwarded call. Subscriber B signs a homing mobile service contract provided by the home network and a mobile roaming service contract provided by the ARP, respectively, then having a homing mobile service and a mobile roaming service provided by the home network and the ARP, respectively. For example, subscriber B is an EU subscriber, i.e., he signs a homing mobile service contact with a homing mobile operator in an EU country, and signs a mobile roaming service contract with another ARP, the roaming service area of which ARP covers other EU countries.

It should be noted that although an EU subscriber is used as an example herein, such example serves only a purpose of explaining and illustrating the present invention, which should not be construed as any limitation to the present invention. Any other circumstances suitable for controlling the separated charging of a later forwarded call of a roaming subscriber in the present invention should be included within the patented scope of the present invention. For example, a subscriber signs a homing mobile service contract with the China Mobile and signs a mobile roaming service contract with the China Unicom; when the subscriber is in a homing area, the charging system of the China Mobile charges his data traffic, when the subscriber is in a roaming area covered by the mobile roaming service contract, the charging system of the China Unicom charges his data traffic.

Referring to Fig. 1, according to one embodiment of the present invention, subscriber B has a homing mobile service within one EU country provided by the home network and a mobile roaming service within other EU countries provided by the ARP.

In step S101, when subscriber B has an incoming call and is in a service area of ARP, the call control apparatus requests the ARP OCS to charge the subscriber B's data service.

When subscriber B has an incoming call from the calling party A, the GMSC of the home network sends a MTC (Mobile Terminated Call) charging request to the call control apparatus.

The call control apparatus manages the EU roaming rules. The call control apparatus queries the HLR (Home Location Register) to obtain the subscriber B's current location, e.g., whether subscriber B is roaming in an EU country. When subscriber B is roaming in another EU country, the call control apparatus sends a charging request to ARP OCS. The ARP is pre-selected by subscriber B to provide roaming services and charging. According to EU roaming regulation III, the MTC call before call forwarding, i.e., the initial call to subscriber B, should be charged by the ARP OCS.

The ARP OCS allocates quota based on the roaming tariff plan selected by subscriber B, and returns a response to the charging request to the call control apparatus. The call control apparatus further returns the response to the homing GMSC. Afterwards, the incoming call is routed to the VMSC of the subscriber B's roaming area, such that the VMSC delivers the incoming call to the subscriber B.

In step S102, when the incoming call to the subscriber B is about to be call-forwarded, the call control apparatus determines the OCS corresponding to the later forwarded call; in step S103, when the later forwarded call is transferred to the home network of subscriber B, the call control apparatus requests the OCS of the home network charges the later forwarded call.

In a preferred example, cooperatively referring to Fig. 2, when the incoming call satisfies the trigger condition of the call forwarding, e.g., the subscriber B is in a call, un-reachable or not answering, the VMSC is about to perform call forwarding to the incoming call, and meanwhile detects that the subscriber B has a set of forwarded calls and determines to forward the incoming call to a number C, and then sends a charging request to the call control apparatus. Here, for the later forwarded call in VPLMN, the VMSC supports a CAP interface to HPLMN. The VMSC's support of the CAP interface protocol provides a larger flexibility to the ODiN decision for the call control apparatus.

The call control apparatus receives from the VMSC the number C of the later forwarded call determined thereby, and associates the incoming call and the later forwarded call based on ODiN. Here, the ODiN number, for example, may be a voice mail box, a number of a family, etc. In this way, when the incoming call to subscriber B is about to be call forwarded, the call control apparatus will decide whether the ODiN is applicable: when the number of the later forwarded call is applicable to optimal forwarded-to-number, the call control apparatus determines that the OCS corresponding to the later forwarded call is OCS of the home network; when the number of the later forwarded call is not applicable to the optimal forwarded-to-number, the call control apparatus determines the OCS for charging the later forwarded call based on the home network of the number of the later forwarded call.

Specifically, the evaluating conditions for ODiN are as follow:

- an incoming call, i.e. an ODiN incoming call, shall be in roaming and matched the trigger condition of forwarding call, e.g., no answer, called party busy, non-reachable etc.;

- a call forwarded call, i.e. an ODiN outgoing call, is setup in a roaming network and matches the following conditions:

the called party Number belongs to predefined numbers (e.g. voice mail number); - VMSC network of roaming area belongs to predefined network for which the ODiN service applies;

the type of traffic matches the ones defined for the ODiN service to apply, i.e. speech, fax, video, data etc.;

- an ODiN service is applicable when the following conditions are matched:

- an ODiN incoming call leg exists;

an ODiN outgoing call leg exists;

the following matching criteria apply:

MO and MT ODiN calls belong to the same subscriber account;

the calling party of the MO and MT legs shall be the same; the same traffic types.

When the ODiN service is applicable, the call control apparatus shall perform the following handling:

- release the call forwarding leg from VMSC, i.e. release the ODiN outgoing call leg;

- terminate the charging for incoming call from subscriber A in ARP OCS, i.e. release to end the ODiN incoming call handling in ARP OCS;

- when the incoming leg receives the non-answer, busy, no reachable trigger report from GMSC, the call control apparatus will trigger a new charging request to DSP (Domestic Service Provider) OCS to apply quota for the forwarded call to the number C, and the DSP of home network (DSP OCS) will return the quota reservation result to the call control apparatus; when the incoming leg receives from GMSC other trigger report, e.g. abandon, the incoming call leg shall be released.

- if balance is enough to fund this forwarded number from home network, e.g. number C, the call control apparatus will connect the call to the forwarded number via GMSC. When balance is not enough to fund the forwarded number, the call will be released.

That is, if the later forwarded call is happened in the VPLMN and applicable to the ODiN, the later forwarded call is transferred to the forwarded-to-number (FTN) by the local GMSC, and the later forwarded call does not conform to the EU roaming regulation III and will not be charged by the ARP OCS, but should be charged by the DSP OCS according to a domestic charging model.

If the ODiN is not applicable, the call control apparatus can continue or release the later forwarded call for the VMSC, it is up to the operator's configuration:

- if configured to release the roaming forwarded call, the call control apparatus will release the roaming call leg;

- if configured to continue the roaming forwarded call, the call control apparatus will perform the following evaluation:

when the forwarded number is an EU subscriber, the call will be charged in ARP OCS;

when the forwarded number is a non-EU subscriber, the call will be forwarded according to some operator configuration.

That is, if the later forwarded call happens in the VPLMN and the ODiN is not applicable, the call is transferred to the forwarded-to-number C,

a) if the forwarded number is an EU subscriber, the forwarded roaming call shall still comply with the EU roaming regulation III and shall be charged in ARP OCS;

b) if the forwarded number is a non-EU subscriber, the forwarded roaming call shall be charged in DSP OCS. According to the new EU roaming regulation, for the outgoing call from call forwarding, the calling party and the called party, e.g. subscriber B and subscriber C, should both be EU subscribers.

According to the new EU roaming rules, re-directed/ forwarded call occurs in a home network, which does not use the resources of the roaming network, such that the later forwarded call is not applicable to the new EU roaming rules any more, which should be charged in the DSP OCS; therefore, the call control apparatus should terminate the ARP OCS in charging the incoming call. Before connecting the forwarded-to-number, the call control apparatus should send a new charging request to the DSP OCS to determine whether the subscriber balance is enough to pay the forwarded call. If the balance is enough to pay the forwarded-to-number in the home network, e.g., number C, the call control apparatus will connect this call to the forwarded-to-number via GMSC; if the balance is not enough to pay the forwarded call, the call control apparatus will release the call. Here, the call control apparatus will evaluate whether the ODiN is applicable to the later forwarded call from the VMSC. When the ODiN is applicable, the later forwarded call from the VMSC will be released, and the call control apparatus will connect the incoming call to the ODiN number via the incoming leg locally. This will avoid establishing two calls for the incoming call: the first call is calling party → GMSC → VMSC; the second call is VMSC → GMSC → forwarded-to-number (e.g., a voice mail box). The ODiN service may reduce unnecessary roaming expenses.

Alternatively, the VMSC can evaluate ODiN to determine the optimal number C to which the later call of the subscriber B is forwarded; subsequently, the call control apparatus may directly determine the OCS corresponding to the later forwarded call based on the optimal number C.

In another preferred example, cooperatively referring to Fig. 3, when the incoming call satisfies the trigger condition of call forwarding, e.g., subscriber B is in a call, un-reachable or no answer, the VMSC intends to perform call forwarding to the incoming call, and meanwhile the VMSC detects that the subscriber B has a set of forwarded calls and determines to forward the incoming call to the number C. further, the VMSC may evaluate ODiN to determine that the number C is the optimal number to which the later forwarded call of the subscriber B can be diverted. Here, for the later forwarded call in the VPLMN, the VMSC does not support the CAP interface to HPLMN.

The VMSC sends a MAP RCH (Resume Call Handling) message to return FTN and O-CSI to the GMSC which releases the call connection to VMSC.

Afterwards, the GMSC continues the call forwarded process. Before performing the call forwarding, the GMSC sends a BCSM event report to the call control apparatus, wherein the BCSM event specific information includes a BCSM event (T-Busy or T-No answer BCSM event) and the forwarded-to-number.

The call control apparatus receives the number of the later forwarded call from GMSC. According to the new EU roaming rules, the re-directed/ forwarded call occurs in the home network, which does not use the resources of the roaming network, such that the later forwarded call is not applicable to the new EU roaming rules any more, which should be charged by the DSP OCS; therefore, the call control apparatus should terminate the ARP OCS in charging the incoming call. Before connecting the forwarded-to-number, the call control apparatus should send a new charging request to the DSP OCS to determine whether the subscriber balance is enough to fund the forwarded call. If the balance is sufficient to fund the forwarded call in the home network, e.g., number C, the call control apparatus will connect the call to the forwarded-to-number via the GMSC; if the balance is not enough to fund the forwarded-to-number, the call control apparatus will release the call.

Cooperatively referring to Figs. 2 and 4, an EU subscriber is roaming in another EU country, the subscriber B has an incoming call, and the subscriber B is busy with an ongoing call, cannot answer the incoming call.

The incoming call is forwarded to a number C. The ODiN is applicable to both the incoming call and the forwarded call, but the forwarded-to-number is not a free number. When the incoming call is forwarded to number C via GMSC locally, the later forwarded call should be monitored.

The interfaces from the call control apparatus to the ARP OCS and DSP OCS are both Diameter online charging interface.

Steps S401-S410 show that the initial incoming call to subscriber B is charged by the ARP OCS. Steps S411-S416 show that when the subscriber B is busy, the VMSC intends to perform call forwarding to the incoming call, and notifies the call control apparatus of the forwarded-to-number C to which the incoming call is call forwarded; when the call control apparatus evaluates that ODiN is applicable, the later forwarded call from the VMSC is released. Steps S417-S419 show that after the call control apparatus receives the BCSM event report that subscriber B is busy, it sends a request to terminate the ARP OCS in charging the incoming call. Steps S420-S421 show that the call control apparatus sends a charging request to the DSP OCS to charge the forwarded-to-call which is not a free number, and the DSP OCS will allocate a quota to the forwarded call. Step S422 shows that the call control apparatus re-configures trigger condition and connects the call to the forwarded-to-number via GMSC locally. Step S423 shows that after the forwarded call is answered, the GMSC sends a BCSM event report to the call control apparatus which will record the call time. Steps S424-S426 show that, after the call is terminated, the GMSC sends a BCSM event report and a charging application report to the call control apparatus, and the call control apparatus sends a charging request to the DSP OCS to deduct expenses from the subscriber balance.

Cooperatively referring to Figs. 2 and 5, an EU subscriber B is roaming in another EU country, the subscriber B has an incoming call, but the subscriber B is busy with an ongoing call and cannot answer the incoming call. The incoming call is forwarded to a number C. The ODiN is applicable to both the incoming call and the forwarded call both, but the forwarded-to-number is a free number. When the incoming call is forwarded to the number C by the call control apparatus via the GMSC locally, the later forwarded call should not be monitored. The interfaces from the call control apparatus to ARP OCS and DSP OCS are both Diameter based interface.

Steps S501-S510 show that the initial incoming call to subscriber B is charged by the ARP OCS. Steps S511-S516 show that when subscriber B is busy, the VMSC will perform call forwarding to the incoming call and notify the call control apparatus that the incoming call is call forwarded to the forwarded-to-number C; when the call control apparatus determines that the ODiN applies, the later forwarded call from the VMSC is released. Steps S517-S519 show that after the call control apparatus receives a BCSM event report that subscriber B is busy, it sends a request for terminating the ARP OCS in charging the incoming call. Steps S520-S521 show that the call control apparatus sends a charging request to the DSP OCS to charge the forwarded call; the forwarded-to-number is a free number, and the DSP OCS is not required to allocate a quota to the forwarded call. Step S522 shows that the call control apparatus cancels the trigger configuration set previously. Step S523 shows that the call control apparatus connects the call to the forwarded-to-number and terminates the call.

Cooperatively referring to Figs. 2 and 6, an EU subscriber B is roaming in another EU country, the subscriber B has an incoming call, but the subscriber B is busy with an ongoing call, cannot answer the incoming call.

The incoming call will be forwarded to a number C. The ODiN is not applicable to both the incoming call and the forwarded call; but the forwarded-to-number is an EU number.

The interface from the call control apparatus to the ARP OCS is Diameter based interface. The interface from the call control apparatus to the DSP OCS is CAP/CS1 charging interface.

Steps S601-S610 show that the initial incoming call to subscriber B is charged by the ARP OCS. Steps S611-S616 show that when subscriber B is busy, the VMSC will perform call forwarding to the incoming call and notifies the call control apparatus of the forwarded-to-number C to which the incoming call is call forwarded; when the call control apparatus determines that the ODiN is not applicable, the later forwarded call from the VMSC continues using the quota allocated by the ARP OCS. Steps S617-S632 show a process in which the ARP OCS charges the forwarded call. Here, the incoming roaming call triggered by GMSC and the outgoing forwarded call triggered by VMSC are both charged by the ARP OCS.

Cooperatively referring to Figs. 2 and 7, an EU subscriber B is roaming in another EU country, the subscriber B has an incoming call, and the subscriber B is in a call and cannot answer the incoming call.

The incoming call is forwarded to a number C. The ODiN is not applicable to both the incoming call and the forwarded call; the forwarded-to-number is not an EU number; the call forwarding for this incoming call is not allowed.

The interfaces from the call control apparatus to ARP OCS and DSP OCS are both Diameter charging interfaces

Steps S701-S710 show that the initial incoming call to subscriber B is charged by the ARP OCS. Steps S711-S716 show that when subscriber B is busy, the VMSC will perform call forwarding to the incoming call and notifies the call control apparatus of the forwarded-to-number C to which the incoming call is call forwarded; when the call control apparatus determines that the ODiN is not applicable, the later forwarded call from the VMSC is released. Steps S717-S720 show that the call control apparatus terminates the ARP OCS in charging the incoming call. Cooperatively referring to Figs. 2 and 8, an EU subscriber B is roaming in a non-EU country, the subscriber B has an incoming call; the subscriber is in a call and cannot answer this incoming call.

The incoming call will be forwarded to a number C. The ODiN is applicable to both the incoming call and the forwarded call. The forwarded-to-number is a free number. When the incoming call is forwarded to the number C by the call control apparatus via the GMSC locally, the later forwarded call needs not to be monitored.

The interfaces from the call control apparatus to the ARP OCS and the DSP OCS are both Diameter charging interfaces.

Steps S801-S809 show that the incoming call to subscriber B is charged by the DSP OCS. Steps S810-S815 show that when the subscriber B is busy, the VMSC will perform call forwarding to the incoming call and notifies the call control apparatus of the forwarded-to-number C to which the incoming call is call forwarded; when the call control apparatus determines that the ODiN is applicable, the later forwarded call from the VMSC is released. Steps S816-S818 show that after the call control apparatus receives a BCSM event report that the subscriber B is busy, it sends a request for terminating the DSP OCS in charging the forwarded call. Steps S819-S820 show that the call control apparatus sends a charging request to the DSP OCS to charge the forwarded call. The forwarded-to-number is a free number, and the DSP OCS needs not to allocate a quota to the forwarded call. Step S821 shows a trigger configuration before cancellation of the call control apparatus. Step S822 shows that the call control apparatus connects the call to the forwarded-to-number and terminates the call. Cooperatively referring to Figs. 2 and 9, an EU subscriber B is roaming in a non-EU country, and the subscriber B has an incoming call; the subscriber B is in a call and cannot answer the incoming call.

The incoming call will be forwarded to a number C. The ODiN is not applicable to both the incoming call or the forwarded call.

The interfaces from the call control apparatus to the ARP OCS and the DSP OCS are both Diameter charging interfaces. Steps S901-S909 show that the initial incoming call to subscriber B is charged by the DSP OCS. Steps S910-S917 show that when the subscriber B is busy, the VMSC will perform call forwarding to the incoming call and notifies the call control apparatus of the forwarded-to-number C to which the incoming call is forwarded, such that when the call control apparatus determines the ODiN is not applicable, the later forwarded call from the VMSC will continue based on the quota allocated by the DSP OCS. Steps S918-S929 show a process in which the DSP OCS charges the forwarded call. Here, the incoming roaming call triggered by the GMSC and the outgoing forwarded call triggered by the VMSC are both charged by the DSP OCS. Cooperatively referring to Fig. 3 and Fig. 10, an EU subscriber B is roaming in another EU country, the subscriber B has an incoming call, but the subscriber B is in a call and cannot answer the incoming call.

The incoming call is forwarded to a number C. The ODiN is applicable to both the incoming call and the forwarded call, but the forwarded-to-number C is not a free number. When the incoming call is forwarded to the number C by the call control apparatus via the GMSC locally, the later forwarded call should be monitored.

The interfaces of the call control apparatus to the ARP OCS and the DSP OCS are both online charging interfaces.

Steps S1001-S1009 show that the initial incoming call to subscriber B is charged by the ARP OCS. Steps S1010-S1011 show that the call forwarding of the incoming call occurs in VPLMN. Steps S1012-S1015 show that after the call control apparatus receives a BCSM event report that the subscriber B is busy, including FTN and an event report specific message, the call control apparatus sends a request for terminating the ARP OCS in charging the incoming call. Steps S1016-S1017 show that the call control apparatus sends a charging request to the DSP OCS to charge the forwarded call, and the forwarded-to-number is a non-free number such that the DSP OCS allocates a quota to the forwarded call. Step S1018 shows that the call control apparatus cancels the trigger configuration set previously. Step S1019 shows that the call control apparatus requests the GMSC for the BCSM event report. Steps S1020-S1021 show that the GMSC sends an MAP RCH response message to the VMSC after the call is terminated.

Cooperatively referring to Figs. 3 and 11, an EU subscriber B is roaming in another EU country, the subscriber B has an incoming call, but the subscriber B is in a call and cannot answer the incoming call.

The incoming call is forwarded to a number C. The ODiN is applicable to both of the incoming call and the forwarded call, and the forwarded-to-number C is a free number. When the incoming call is locally forwarded to the number C by the call control apparatus via the GMSC, the later forwarded call needs not to be monitored.

The interface from the call control apparatus to the ARP OCS is Diameter based interface. The interface from the call control apparatus to the DSP OCS is Diameter interface. Steps S1101-S1109 show that the initial incoming call to subscriber B is charged by the ARP OCS. Steps S1110-S1111 show that call forwarding for the incoming call occurs in VPLMN. Steps S1112-S1115 show that after the call control apparatus receives a BCSM event report that the subscriber B is busy, including FTN and an event report specific message, the call control apparatus sends a request to terminate the ARP OCS in charging the incoming call. Steps S1116-S1117 show that the call control apparatus sends a charging request to the DSP OCS to charge the forwarded call, and the forwarded-to-number is a free number such that the DSP OCS needs not to allocate a quota for the forwarded call. Step S1118 shows that the call control apparatus cancels the trigger configuration set previously. Steps S1119-S1121 show that the call control apparatus connects the call to the forwarded-to-number and terminates the call.

Cooperatively referring to Figs. 2 and 12, according to one embodiment of the present invention, subscriber B has a homing mobile service within one EU country provided by the home network and a mobile roaming service within other EU countries provided by the ARP.

In this embodiment, the call control apparatus cooperated with the VMSC from the roaming area of the subscriber B to control the separated charging of the later forwarded call of the subscriber B.

As shown in Fig. 12, the call control apparatus comprises a first charging request module 1211, a first forwarding receiving module 1212, an OCS determining module 1213 and a second charging request module 1214; VMSC comprises a forwarded-to-number determining module 1221 and a first forwarding sending module 1222.

Specifically, when subscriber B has an incoming call and is in a service area of ARP, the first charging request module 1211 requests the ARP OCS to charge the subscriber B's data service.

For example, when subscriber B has an incoming call from the calling party A, the GMSC of the home network sends a MTC (Mobile Terminated Call) charging request to the call control apparatus.

The call control apparatus manages the EU roaming rules. The call control apparatus queries the HLR (Home Location Register) to obtain the subscriber B's current location, e.g., whether subscriber B is roaming in an EU country. When subscriber B is roaming in another EU country, the first charging request module 1211 of the call control apparatus sends a charging request to ARP OCS. The ARP is pre-selected by subscriber B to provide roaming services and charging. According to EU roaming regulation III, the MTC call before call forwarding, i.e., the initial call to subscriber B, should be charged by the ARP OCS.

The ARP OCS allocates quota based on the roaming tariff plan selected by subscriber B, and returns a response to the charging request to the call control apparatus. The first charging request module 1211 further returns the response to the homing GMSC. Afterwards, the incoming call is routed to the VMSC of the subscriber B's roaming area, such that the VMSC delivers the incoming call to the subscriber B.

When the incoming call satisfies the trigger condition of the call forwarding, e.g., the subscriber B is in a call, un-reachable or not answering, the VMSC is about to perform call forwarding to the incoming call, and meanwhile the forwarded-to-number determining module 1221 of the VMSC detects that the subscriber B has a set of forwarded calls and determines to forward the incoming call to a number C, and then the first forwarding sending module 1222 sends a charging request to the call control apparatus. Here, for the later forwarded call in VPLMN, the VMSC supports a CAP interface to HPLMN. The VMSC's support of the CAP interface protocol provides a larger flexibility to the ODiN decision for the call control apparatus.

When the incoming call to the subscriber B is about to be call-forwarded, the first forwarding receiving module 1212 receives from the VMSC the forwarded-to-number to which the incoming call is forwarded; the OCS determining module 1213 determines the OCS corresponding to the later forwarded call; when the later forwarded call is transferred to the home network of subscriber B, the second charging request module 1214 requests the OCS of the home network charges the later forwarded call.

The first forwarding receiving module 1212 receives from the VMSC the number C of the later forwarded call determined thereby, and the OCS determining module 1213 associates the incoming call and the later forwarded call based on ODiN. Here, the ODiN number, for example, may be a voice mail box, a number of a family, etc. In this way, when the incoming call to subscriber B is about to be call forwarded, the OCS determining module 1213 will decide whether the ODiN is applicable: when the number of the later forwarded call is applicable to optimal forwarded-to-number, the OCS determining module 1213 determines that the OCS corresponding to the later forwarded call is OCS of the home network; when the number of the later forwarded call is not applicable to the optimal forwarded-to-number, the OCS determining module 1213 determines the OCS for charging the later forwarded call based on the home network of the number of the later forwarded call.

If the later forwarded call is happened in the VPLMN and applicable to the ODiN, the later forwarded call is transferred to the forwarded-to-number (FTN) by the local GMSC, and the later forwarded call does not conform to the EU roaming regulation III and will not be charged by the ARP OCS, but should be charged by the DSP OCS according to a domestic charging model.

If the later forwarded call happens in the VPLMN and the ODiN is not applicable, the call is transferred to the forwarded-to-number C,

a) if the forwarded number is an EU subscriber, the forwarded roaming call shall still comply with the EU roaming regulation III and shall be charged in ARP OCS;

b) if the forwarded number is a non-EU subscriber, the forwarded roaming call shall be charged in DSP OCS. According to the new EU roaming regulation, for the outgoing call from call forwarding, the calling party and the called party, e.g. subscriber B and subscriber C, should both be EU subscribers. According to the new EU roaming rules, re-directed/ forwarded call occurs in a home network, which does not use the resources of the roaming network, such that the later forwarded call is not applicable to the new EU roaming rules any more, which should be charged in the DSP OCS; therefore, the call control apparatus should terminate the ARP OCS in charging the incoming call. Before connecting the forwarded-to-number, the call control apparatus should send a new charging request to the DSP OCS to determine whether the subscriber balance is enough to pay the forwarded call. If the balance is enough to pay the forwarded-to-number in the home network, e.g., number C, the call control apparatus will connect this call to the forwarded-to-number via GMSC; if the balance is not enough to pay the forwarded call, the call control apparatus will release the call.

Here, the OCS determining module 1213 of the call control apparatus will evaluate whether the ODiN is applicable to the later forwarded call from the VMSC. When the ODiN is applicable, the later forwarded call from the VMSC will be released, and the call control apparatus will connect the incoming call to the ODiN number via the incoming leg locally. This will avoid establishing two calls for the incoming call: the first call is calling party ^→ GMSC ^→ VMSC; the second call is VMSC ^→ GMSC ^→ forwarded-to-number (e.g., a voice mail box). The ODiN service may reduce unnecessary roaming expenses. Alternatively, the forwarded-to-number determining module 1221 of the VMSC can evaluate

ODiN to determine the optimal number C to which the later call of the subscriber B is forwarded; subsequently, the OCS determining module 1213 of the call control apparatus may directly determine the OCS corresponding to the later forwarded call based on the optimal number C. Cooperatively referring to Fig. 3 and fig. 13, according to another embodiment of the present invention, subscriber B has a homing mobile service within one EU country provided by the home network and a mobile roaming service within other EU countries provided by the ARP.

In this embodiment, the call control apparatus cooperated with the GMSC from the homing location of the subscriber B and the VMSC from the roaming location thereof to control the separated charging of the later forwarded call of the subscriber B.

As shown in Fig. 13, the call control apparatus comprises a first charging request module 1311, a second forwarding receiving module 1312, an OCS determining modulel313 and a second charging request module 1314; GMSC comprises a forwarding receiving module 1331 and a forwarding sending module 1332; VMSC comprises a forwarded-to-number determining module 1321 and a second forwarding sending module 1322.

Specifically, when subscriber B has an incoming call and is in a service area of ARP, the first charging request module 1311 requests the ARP OCS to charge the subscriber B's data service.

The call control apparatus manages the EU roaming rules. The call control apparatus queries the HLR (Home Location Register) to obtain the subscriber B's current location, e.g., whether subscriber B is roaming in an EU country. When subscriber B is roaming in another EU country, the first charging request module 1311 of the call control apparatus sends a charging request to ARP OCS. The ARP is pre-selected by subscriber B to provide roaming services and charging. According to EU roaming regulation III, the MTC call before call forwarding, i.e., the initial call to subscriber B, should be charged by the ARP OCS.

The ARP OCS allocates quota based on the roaming tariff plan selected by subscriber B, and returns a response to the charging request to the call control apparatus. The first charging request module 1311 further returns the response to the homing GMSC. Afterwards, the incoming call is routed to the VMSC of the subscriber B's roaming area, such that the VMSC delivers the incoming call to the subscriber B. when the incoming call satisfies the trigger condition of call forwarding, e.g., subscriber B is in a call, un-reachable or no answer, the VMSC intends to perform call forwarding to the incoming call, and meanwhile the forwarded-to-number determining module 1321 of the VMSC detects that the subscriber B has a set of forwarded calls and determines to forward the incoming call to the number C. further, the forwarded-to-number determining module 1321 may evaluate ODiN to determine that the number C is the optimal number to which the later forwarded call of the subscriber B can be diverted. Here, for the later forwarded call in the VPLMN, the VMSC does not support the CAP interface to HPLMN.

The second forwarding sending module 1322 of the VMSC sends a MAP RCH (Resume Call Handling) message to return FTN and O-CSI to the GMSC which releases the call connection to VMSC. Afterwards, the GMSC continues the call forwarded process. Before performing the call forwarding, the forwarding receiving module 1332 of the GMSC sends a BCSM event report to the call control apparatus, wherein the BCSM event specific information includes a BCSM event (T-Busy or T-No answer BCSM event) and the forwarded-to-number. The second forwarding receiving module 1312 of the call control apparatus receives the number of the later forwarded call from GMSC. According to the new EU roaming rules, the re-directed/ forwarded call occurs in the home network, which does not use the resources of the roaming network, such that the later forwarded call is not applicable to the new EU roaming rules any more, which should be charged by the DSP OCS; therefore, the OCS determining modulel313 of the call control apparatus should terminate the ARP OCS in charging the incoming call. Before connecting the forwarded-to-number, the second charging request module 1314 of the call control apparatus should send a new charging request to the DSP OCS to determine whether the subscriber balance is enough to fund the forwarded call. If the balance is sufficient to fund the forwarded call in the home network, e.g., number C, the call control apparatus will connect the call to the forwarded-to-number via the GMSC; if the balance is not enough to fund the forwarded-to-number, the call control apparatus will release the call.

It should be noted that the present invention may be implemented in software or a combination of software and hardware; for example, it may be implemented by an ASIC (Application Specific Integrated Circuit), a general-purpose computer, or any other similar hardware devices.

The software program of the present invention may be executed by a processor to implement the above steps or functions. Likewise, the software program of the present invention (including relevant data structure) may be stored in a computer readable recording medium, for example, a RAM memory, a magnetic or optical driver, or a floppy disk, and other similar devices. Besides, some steps or functions of the present invention may be implemented by hardware, for example, a circuit cooperating with a processor to execute various functions or steps.

Additionally, a portion of the present invention may be applied as a computer program product, for example, a computer program instruction, which, may invoke or provide a method and/or technical solution according to the present invention through operations of the computer when executed by the computer. Further, the program instruction invoking the method of the present invention may be stored in a fixed or mobile recording medium, and/or transmitted through broadcast or data flow in other signal bearer media, and/or stored in a working memory of a computer device which operates based on the program instruction. Here, one embodiment according to the present invention comprises an apparatus comprising a memory for storing a computer program instruction and a processor for executing the program instruction, wherein when the computer program instruction is executed by the processor, the apparatus is triggered to run the methods and/or technical solutions according to a plurality of embodiments of the present invention.

To those skilled in the art, it is apparent that the present invention is not limited to the details of the above exemplary embodiments, and the present invention may be implemented with other embodiments without departing from the spirit or basic features of the present invention. Thus, in any way, the embodiments should be regarded as exemplary, not limitative; the scope of the present invention is limited by the appended claims instead of the above description, and all variations intended to fall into the meaning and scope of equivalent elements of the claims should be covered within the present invention. No reference signs in the claims should be regarded as limiting of the involved claims. Besides, it is apparent that the term "comprise" does not exclude other units or steps, and singularity does not exclude plurality. A plurality of units or modules stated in a system claim may also be implemented by a single unit or module through software or hardware. Terms such as the first and the second are used to indicate names, but do not indicate any particular sequence.