US 20050250493 A1
A method, system and gateway for control of calls unanswered by a roaming user roaming on a roaming network, comprises monitoring outward bound calls to roaming users, monitoring subsequent inward forwarding of those calls terminated without answering at said roaming users, and matching between the outward bound and inward forwarding. Matching confers control of processing of the terminated call in two ways. One is that it allows call details, typically lost over International networks, to be obtained regarding the terminated call. Secondly, it allows the originating call to be connected directly to the voicemail or other forwarding destination without involving any International connections.
1. A call management system for calls to roaming users currently connected in a first, roaming, network, said roaming network being distinct from a home network of said roaming user, which calls are unanswered by said roaming users, the system comprising:
a call tracking unit for tracking calls routed to said roaming user at said roaming network, said call tracking unit having a memory unit for retaining details of said call until said call is either answered or unanswered, and further for tracking calls unanswered and forwarded to a predetermined forwarding location from said roaming network, and
a data management unit configured to use said retained details to permit subsequent management of said call within the confines of said home network.
2. The system of
3. The system of
4. The system of
5. The system of
6. The system of
7. The system of
8. The system of
9. The system of
10. The system of
11. The system of
12. The system of
13. The system of
14. The system of
15. The system of
16. The system of
17. The system of
18. The system of
19. A gateway for International roaming at roaming networks distinct from a home network with which said gateway and respective users are associated, the gateway comprising:
a call tracking unit for tracking calls routed to a roaming user at a roaming network, said call tracking unit having a memory unit for retaining details of said call until said call is either answered or unanswered, and further for tracking calls unanswered and forwarded to a predetermined forwarding location from said roaming network, and
a call management unit, configured to use said retained details to permit subsequent management of said unanswered call within the confines of said home network.
20. The gateway of
21. The gateway of
22. The gateway of
23. The gateway of
24. The gateway of
25. The gateway of
26. The gateway of
27. The gateway of
28. The gateway of
29. The gateway of
30. The gateway of
31. A method for control of calls terminated without answering at a roaming user roaming on a network apart from a respective home network of said user, the method comprising at the home network,
monitoring outward bound calls to roaming users and obtaining data of said outward bound calls,
monitoring inward forwarding of said calls unanswered by said roaming users,
matching between said outward bound and inward forwarding, thereby to find respective obtained data of said inward forwarded calls and thus confer control of processing of unanswered calls to said home network.
32. The method of
33. The method of
34. The method of
35. The method of
36. The method of
The present application claims priority from U.S. Provisional Patent Application No. 60/519,652 filed Nov. 14, 2003, the contents of which are hereby incorporated by reference.
The present invention relates to methods, systems and apparatus for terminated call control for roaming cellular telephony.
Systems for supporting mobile telephones when they are outside their home network geographical areas, a phenomenon known as roaming, are well known. Generally a mobile telephone moves within the geographical area of its home network, typically a country, and within that country it moves around different base stations and local visitor location registers (VLRs). When the telephone is outside the geographical region of the network, then it connects to a foreign network, and registers at a roaming VLR. The VLR checks for the corresponding home location register (HLR) to verify the telephone and then allows calls to proceed. The HLR makes a note of the currently responding VLR so that any calls to the telephone can be routed from the HLR to the VLR and the call can be completed.
One phenomenon that occurs with International calls to roamers occurs with call forwarding to mailboxes or to other numbers and is known as tromboning. The calling party calls the roamer who does not answer. The unsuccessful caller is then forwarded from the roamer to the roamer's mailbox where he leaves a message. At this point the calling party is connected via an outgoing international leg to the roamer and then via a second incoming international leg back to the roamer's home network where his voicemail is located. When this happens the calling party pays for a local call, since he dialed a local number. The called party however has to pay for two international legs of the call, all this for a call that he did not even answer. The phenomenon is known as tromboning, and leads to substantial ill feeling and customer care issues with subscribers, so much so that many are induced not to use roaming at all, or at least to cancel their mailboxes whilst roaming, leading to substantial loss of opportunity for farther calls.
An additional issue with roaming is that telephone numbers or caller identifications are often lost over international lines, so that the calling number does not appear on the roamer's screen, preventing him from carrying out his own call screening and preventing him from returning calls he was unable to answer.
In more detail, Mobile subscribers normally set call forwarding instructions to the voicemail. Late Call Forwarding is performed conditionally due to the subscriber's inability to answer a call routed to the handset. Conversely, Early Call Forwarding is performed without the network's attempt to route the call to the handset. This happens when the handset is shut off or when the subscriber requests unconditional forwarding of all incoming calls. Late Call Forwarding for busy/no-answer/not-reachable conditions can be configured to any number, usually to the subscriber's voice mailbox.
Mobile subscribers roaming abroad want to stay in touch with work and home, and continue to use their mobile services, such as voicemail. They also naturally want the same user experience as in the home network—such as seamless caller access to mailbox, caller-ID indication in retrieval and direct forwarding of calls to their voice mailbox or to any of their pre-set forwarding destinations.
However, when a roamer cannot take a call—either unavailable, busy or chooses not to answer—the visited network routes the call back to the home voicemail system (the default setting for most roamers). This in turn causes inefficient international tromboning, resulting in a negative impact on the caller and subscriber experience, and forces roamers to pay international tariffs for voicemail deposits.
Higher subscriber costs—The high cost caused by international tromboning of voicemail causes many roamers to disable voicemail forwarding while roaming or even turn off their handsets. Some home networks just disable call forwarding for their outbound roaming subscribers in order to avoid subscriber frustration.
Complicated use—Due to filtering of signaling data by switch vendors and by some international networks, the original dialed number may not be transferred to the home network's voicemail system, forcing the caller to reenter the original dialed number. For the same reasons Caller ID is not available to the voicemail system, thus the phone number of the caller is not provided during message retrieval.
Higher operator costs—Roaming subscribers who are unaware of the high cost of forwarding calls may be surprised and angered when receiving their monthly bills. The immediate response is usually to call Customer Care to complain and inquire about the charges. In addition to customer dissatisfaction, this in turn engages operator's manpower and communications resources.
Lost of potential revenue—Disabling call forwarding to voicemail while roaming—either by the subscriber or by the operator—means loss of potential revenue that otherwise would have come from:
There is thus a widely recognized need for, and it would be highly advantageous to have, a terminated call management system for roaming cellular telephony subscribers which is devoid of the above limitations.
According to one aspect of the present invention there is provided a call management system for unanswered calls to roaming users currently connected in a first, roaming, network, the roaming network being distinct from a home network of the roaming user, the system comprising:
Preferably, the data management unit comprises a matching unit for comparing details of the call being forwarded to the roamer with details of the call being forwarded to the forwarding location, thereby to obtain a match therebetween and obtain respective call details of the call being forwarded to the forwarding location.
The system may further comprise a release unit, associated with the call tracking unit, configured to indicate to the roaming network to release the call.
The system may further comprise a fording modification unit for changing forwarding setting of a given user when it is determined that the user is roaming.
Preferably, the memory unit is a loop, for storing the details for a predetermined number of time slots.
The system may comprise a probe, associated with the call tracking unit and the call release unit, for identifying events comprising at least one of a call being forwarded to a roamer and a subsequent event of a call being forwarded to a predetermined forwarding location.
The system may be configured to use network triggers to identify events comprising at least one of a call being forwarded to a respective roamer and a call being forwarded to a predetermined forwarding location.
The system is preferably configured to route a matched call directly to the predetermined forwarding location.
The system is preferably configured to route a matched call according to preset forwarding rules.
The system may comprise a forwarding modification unit for modifying forwarding settings of given users when they are found to be roaming.
The system's comparator or matching unit is preferably able to compare details of the call being forwarded to the roamer with details of the call being forwarded to the forwarding location, thereby to connect the call being forwarded directly to the forwarding location.
The comparator is preferably able to compare details of the call being forwarded to the roamer with details of the call being forwarded to the forwarding location, thereby to obtain a match therebetween and obtain respective call details of the call being forwarded to the forwarding location.
The system may be configured to send the call details to the forwarding location, the call details comprising caller identity information.
The system may be configured to include the caller identity information in a text message to the roamer.
Preferably, the forwarding location is a voicemail of the roamer.
The system may use different forwarding locations for different circumstances according to any kind of logical scheme, for example it may use a different forwarding location dependent upon a reason for forwarding the call from the roamer to the forwarding location.
The reasons used may include the roaming unit being unavailable to the network, the roaming unit being busy with another call, the roaming unit not answering, and a generic call not completed to the roamer.
In an embodiment, the memory unit is a loop, for storing the details for a predetermined number of time slots.
According to a second aspect of the present invention there is provided a gateway for International roaming at roaming networks distinct from a home network with which the gateway and respective users are associated, the gateway comprising:
The gateway may comprise a release unit, associated with the call management unit, configured to indicate to the roaming network to release the forward call.
The gateway may comprise a matching unit for matching between a routed call and the forwarding, thereby to obtain the retained information from the routed call for the forwarding.
The gateway may comprise a probe, associated with the call tracking unit and the call release unit, for identifying an event comprising at least one of the call being routed to the roamer and a subsequent event of the call being forwarded to the predetermined forwarding location.
The gateway may comprise a comparator for comparing details of calls being firstly routed to respective roaming users, with details of calls being forwarded to respective forwarding locations, thereby to match the calls and obtain call detail information corresponding to a call being forwarded to the forwarding location.
The gateway may comprise using the call detail information to directly connect the firstly forwarded call to the forwarding location within the confines of the home network.
The gateway may comprise a comparator for comparing details of the call being routed to the roamer with details of the call being forwarded to the forwarding location, thereby to obtain caller identification details of the call being forwarded.
The gateway may be configured to send the caller identification details to the forwarding location.
The gateway may be configured to include the identification details in a text message to the roamer.
The forwarding location may be a voicemail of the roamer, or there could be a number of locations depending on a logical scheme, for example different locations depending on whether the reason for forwarding is any of the roaming unit being unavailable to the network, the roaming unit being busy with another call, the roaming unit not answering, and a generic call not completed to the roamer.
According to a third aspect of the present invention there is provided a method for control of calls terminated without answering at a roaming user roaming on a network apart from a respective home network of the user, the method comprising at the home network,
The method may comprise forwarding the matched outward bound call directly to a forwarding location on the home network and issuing a release signal to a respective roaming network.
In an embodiment, the details comprise caller identification information.
The method may comprise forwarding the caller identification information to a predetermined forwarding location.
In an embodiment, the predetermined forwarding location is a voicemail.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples provided herein are illustrative only and not intended to be limiting.
Implementation of the method and system of the present invention involves performing or completing certain selected tasks or steps manually, automatically, or a combination thereof. Moreover, according to actual instrumentation and equipment of preferred embodiments of the method and system of the present invention, several selected steps could be implemented by hardware or by software on any operating system of any firmware or a combination thereof. For example, as hardware, selected steps of the invention could be implemented as a chip or a circuit. As software, selected steps of the invention could be implemented as a plurality of software instructions being executed by a computer using any suitable operating system. In any case, selected steps of the method and system of the invention could be described as being performed by a data processor, such as a computing platform for executing a plurality of instructions.
The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in order to provide what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.
In the drawings:
The present embodiments comprise a method for control of calls terminated without answering at a roaming user roaming on a network apart from a respective home network of said user, the method is based on the home network, and involves monitoring outward bound calls to roaming users and obtaining data of said outward bound calls, monitoring inward forwarding of said calls unanswered by said roaming users, and matching between said outward bound and inward forwarding, thereby to find respective obtained data of said inward forwarded calls and thus confer control of processing of unanswered calls to said home network. Matching between outgoing roaming calls and incoming call terminations, allows the international leg of the call can be released and the originating outgoing call can be connected to the voicemail or other forwarding location directly. Furthermore, call detail information, such as caller ID, generally lost over the International connection, can be obtained by the voicemail. If desired the caller ID can be used in a text message to the roamer to inform him that he has a voice mail from the given user ID or that an attempt was made to contact him from that user ID.
Typically the system of the present embodiments is managed at an International gateway of the roamer's home network, referred to hereinbelow as an Intelligent Gateway or by its abbreviations Intelligate or IG.
The principles and operation of an unanswered call control system for roamers according to the present invention may be better understood with reference to the drawings and accompanying description.
Before explaining at least one embodiment of the invention in detail it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.
Reference is now made to
In one embodiment, memory unit 22 is a loop, for storing said details for a predetermined number of time slots.
An embodiment comprises a probe 116 (see
Preferably, there is provided a matching unit or comparator 26 for comparing details of the call being forwarded to the roamer (the outbound leg) with details of the call being forwarded to the forwarding location. It thus becomes possible to connect the call being forwarded directly to the forwarding location.
The comparator allows identification details of the call being forwarded to be obtained directly from the call originator.
These identification details can then be sent to the forwarding location, say the roamer's voicemail. Alternatively, or in addition, they may be included in a text message to the roamer.
In some cases the forwarding location may be different dependent upon a reason for forwarding the call. Thus the roamer may want the call forwarded to his voicemail in certain cases but to his office in other cases for example. Reasons for call termination include the roaming unit being unavailable to the network, that is not connected, the roaming unit being busy with another call, the roaming unit simply not answering, and there may be a generic call not completed case, say if the roaming network does not manage to communicate the reason for failed call completion to the roamer.
The Missed Call Notification (MCN) and Optimal Voicemail Deposit (OVMD) for roamers are two services targeting the roaming subscriber (in the GSM world, although the principles may be adopted for the CDMA and TDMA networks). They both rely on the analysis of the MT (Mobile Terminate) calls routed to the roaming network, and specifically on the CLI information (Caller Line Identification). Hence both services share a common technical solution (although the MCN service has an alternative solution as well).
The following embodiments, referred to as Optimal Voicemail Deposit, overcome the problem of international tromboning, which essentially is caused by incomplete siring when a called party, traveling abroad, cannot answer a call and the call is diverted to the home VMS or to another pre-set forwarding destination.
Optimal Voicemail Deposit improves the caller's experience and significantly reduces the cost of voicemail deposits billed to the roaming subscriber, thereby allowing mobile operators to regain previously lost revenue. The Optimal Voicemail Deposit service provides the following benefits:
Reference is now made to Table 1, which is a glossary of abbreviations known in the art of mobile telephony and which is used in the following description.
Reference is now made to
The Optimal Voicemail Deposit system based on the IntelliGate Roaming SDP 114 can be integrated with the operator's network via GMSC 120 using one of the following two signaling methods:
Based on these two alternative signaling methods, the present embodiments provide a genetic technical solution for the service. The final delivered solution to the operator however must be adjusted to the specific network configuration and parameters such as: network size and topology, traffic volume, INAP vendor's variant, CAMEL version if relevant and the operator's preferences, as will be apparent to the person skilled in the art.
Following is a description of the two signaling options.
Intelligent Network (IN)
Based on the typical IN architecture, the IntelliGate unit 114 controls mobile unanswered delivered to outbound roaming subscribers. This solution is suitable for networks that are already IN or CAMEL ready and/or networks that experience a relatively high outbound rowing traffic.
Using INAP/CS1 or CAP protocols, call control is performed using a combination of Trigger Detection Points and Event Detection points, as will be explained.
In particular cases, such as in a non-IN network environment, relatively low outbound roaming traffic, or if preferred by the operator, call control is performed using ISUP signaling. When a call is not completed—meaning the subscriber does not answer or is not available—the IntelliGate 114 directly routes the call to the called party's voicemail system using only HMPN resources, along with the original called number, as if it was a local call in the home network.
In the ISUP case, the IntelliGate is connected to the MSC. Call control does not require connecting the IntelliGate to the network via voice channels. Rather SS7 signaling links are only used to convey ISUP signaling. This inter-connection is achieved by utilizing a Loop-Around technique on the MSC. The loop around technique is now described.
With Loop-Around, every call requires two ports on the MSC. These ports are connected together to form a loop using a cable so that there is always a voice path between these two ports. The International Intelligent gateway or IntelliGate 114 uses the ISUP signaling for call control to control the looped-around ports using standard ISUP messages.
Using this interface the IntelliGate controls the forwarding settings of roaming subscribers automatically when registering to a foreign network as well when returning back to the operator's network. Control has mainly to do with deactivating and reactivating the forwarding.
The HLR interface is based on standard SS7/MAP signaling.
It should be noted that in some networks automatic deactivation of the forward to number or FTN for a roamer is done by the network. The IntelliGate unit with the functionality herein described obviates this network feature and thus allows the network provider to provide a complete service.
The Intelligate is typically provided with an SS7 compatible probe 116 for monitoring SS7 signaling traffic over International links. The probe, known as the SS7 Mobility Probe allows the IntelliGate to have access to the operator's international SCCP signaling links in a completely passive mode.
This interface is used to obtain the relevant subscriber information such as the MSISDN and the forwarding-to-number (FTN).
In some cases the probe and probe interface can be excluded from the final solution, for example when both the following conditions occur:
The Intelligate is preferably provided with a provisioning interface 122. Provisioning interface 122 allows the management of application parameters and subscriber lists.
For example: the operator allows the provisioning of IMSI/MSISDN numbers of those subscribers who are entitled to use the Optimal Voicemail Deposit service (white list). The same interface can be used to block the service for pre-paid users or certain user groups (block list).
Reference is now made to
Service Initial Stage—Obtaining Roamer's Information
The service initial process refers to non call-related processing. This process includes three main activities:
The following figure depicts the service initial stage and is referred to in the paragraphs below.
Obtaining Subscriber's Information
Using its Mobility Probe 116, the IntelliGate 114 automatically detects a registration event of any outbound roamer belonging to the current network. By monitoring the registration messages such as MAP UpdateLocation and MAP_ISD, the IntelliGate 114 collects the information necessary for the application such as the correlation of the IMSI to MSISDN and the configured FTN's. The system supports both optimal call forwarding to any number or call forwarding only to voicemail. The correlation between IMSI and MSISDN is not required when forwarding to voicemail.
By analyzing the FTN profile, the IntelliGate can understand the subscriber's profile. Based on the forwarding profile we can categorize the subscribers into “default” subscribers and “advanced” subscribers. If the subscriber has requested a different FIN for different cases then the subscriber's profile is considered “advanced”. If all cases are forwarded to the voicemail or disabled then the subscriber's profile considered “default”.
It should be noted that forwarding calls to different destinations based on the release cause is possible only if the release cause is available (returned) to the home GMSC; the system handles exceptions by routing to a default destination. This point is discussed in more detail below.
Check CF in the HLR Directly
Some networks automatically disable call forwarding for roamers; in this case the OVMD service can automatically “learn” the original CF profile of the subscriber and act accordingly. The service uses MAP_INTERROGATE_SS or MAP_SRI requests to the HLR to retrieve the CF information. The information retrieved is used to determine whether or not call forwarding is enabled for the subscriber.
The decision to check the HLR is configured and provisioned in the IntelliGate 114 according to the presently preferred embodiments.
Deactivating Subscriber's Forwarding
Once a successful registration is detected, the IntelliGate 114 sends, if configured (when the network doesn't disable FTN automatically), a MAP_Deactivate_SS message to the HLR and thereby is able to avoid international forwarding from the VPMN to HPMN during roaming.
The deactivation is preferably according to the following rules based on FIN values:
After the initial stage the system preferably checks for any changes in the forwarding information by the subscriber or Customer Care. Both changes appear in a MAP_ISD sent to the serving VLR. The message is preferably monitored and the system may act to reinstate the required changes for the subscriber in order to provide the service according to the following rules, based on the subscriber's requested forward to number, FTN.
Call Control Stage 1—Outgoing Phase
This is the fits call related phase in which the GMSC 108 receives an MT call destined to an outbound roamer. The GMSC, after interrogating the HLR and receiving the MSRN, grants call control to the IntelliGate 114 using INAP or ISUP as appropriate. The main difference between ISUP and IN signaling is the availability of the original called number, i.e. the roamer's MSISDN. The GMSC itself normally does not provide that number in an outgoing call to an international destination, only the MSRN is used for routing. With IN protocols it is anticipated that the OCN is provided as part of the IN query sent by the MSC/SSP.
The present embodiments provide a solution for the missing MT MSISDN based on monitoring the MAP signaling as described below. Alternatively the operator may wish to acquire a solution from its MSC vendor.
Once granted control over the call, the IntelliGate 114 routes the call via the GMSC 108 and the international carrier 124 to VPMN 126 at the roamer's current location. The visited serving MSC tries to extend the call to the roamer. The roamer may not answer for any of the three reasons—no reply, busy and not reachable.
Call Control Stage 2—Forwarding Phase
In this stage the IntelliGate 114 offers two scenarios which can be configured for the convenience of the network operator.
FTN Disabled in HLR
If the subscriber FTN profile has previously been disabled in the HLR 128, say via an HLR Interface, prior to controlling the call, then the visited MSC/VLR has no active forwarding information and therefore releases the call.
Once the IntelliGate 114 receives the release signal from the visited MSC, it forwards the call via the GMSC to the pre-configured FIN which will in many cases be the VMS. The IntelliGate will make the caller's CLI and the roamer's MSISDN available to the VMS.
For DLCF function, if the IntelliGate receives a meaningful release cause it preferably forwards the call according to the value to the FTN indicated in the profile for that release cause.
FTN Profile Not Changed
On subscriber Busy, No Answer or Not Reachable, the VMSC forwards the call to the requested FTN. If the requested FTN is the voicemail, in fact the usual default, then the call is routed back to the HPMN.
The H-GMSC is configured to route forwarded calls arriving from foreign networks and having specific DNs (=Voicemail deposit) to the IntelliGate.
Once the IntelliGate receives the forwarded call, then the call itself is released. This, in turn, causes the originally routed call to be released. That is to say the double international leg or trombone is released. Upon receiving this release the IntelliGate routes the originator's call via the GMSC to the reconfigured MN, which is in most cases, the VMS. The IntelliGate then makes available the caller's CLI and the roamer's MSISDN to the VMS.
Some networks may not receive the release cause from the international links, say Busy, etc. In this case the release caused received is changed to a default or common cause, for example: NORMAL UNSPECIFIED.
The default case is handled in 3 levels:
Service Final Stage—Reactivating Subscriber's Forwarding
Firstly it is pointed out that if the HLR reactivates the subscriber's FTN automatically when returning to the home network, then this stage is not active.
The Optimal Voicemail Deposit service ensue that once the roamer returns to its HPMN the original forwarding settings arm reactivated. This is done by monitoring the MAP_CANCEL message on the international signaling links. Per each detected CANCEL message the time interval between this event and the prior MAP_ISD event is measured. If this time is longer than a predefined time parameter then the IntelliGate queries the HLR using the MAP_SRI_SM message to obtain the address of the roamer's serving MSC/VLR. If the MSC/VLR's address belongs to HPMN's network than it is concluded td the roamer has returned to the home network. In this case the IntelliGate sends a MAP_Activate_SS message to the HLR.
If the MSC/VLR's address is still a foreign one (a different VPMN) than the application must have received a previous MAP_ISD message for the new VPMN. This message confirms that the subscriber is still but in a new VPMN.
Networks which have deactivated call forwarding automatically on roaming (by the HLR, without the IntelliGate's intervention) typically have to reactivate the original call forwarding when the subscriber returns home.
Reference is now made to
Because the same forward-to-number is used when the subscriber is not reachable for both Early Call Forwarding and Late Call Forwarding, disabling the FTN while roaming might prevent voicemail activation for Early Call Forwarding (e.g. handset is off).
To avoid loss of traffic to voicemail with Early Call Forwarding it is advisable not to disable CFNRC and allow trombone. If the CFNRC is directed to the Voicemail the GMSC is preferably configured to send an additional trigger to the IntelliGate to allow the Optimal Voicemail Deposit service to release the call, and thereby release the trombone. The trombone release causes a release in the first call leg that instructs the service to redirect the call to the voicemail, locally.
Reference is now made to
Although operators might wish to offer the Optimal Voicemail Deposit service to both post-paid and pre-paid users, the prepaid system architecture introduces technical challenge to the flow of the service. The reason is that the pre-paid system is always the first to process the call. When the Optimal Voicemail Deposit processes the call after the pre-paid system the call, although answered by the local VMS, appears to the prepaid system as if the roamer was the one who answered. This in turn causes the pre-paid user to pay one international leg for VM deposit.
The present embodiments offer several solutions targeted for different network constellations and vendors. However if the operator prefers to block prepaid users from the service altogether then it can provision the application with either of the two:
Optimal Voicemail Deposit service offers operators the following benefits:
The method described up to now involves interfacing directly with the HLR, and sending a command modifying the forwarding information.
Alternatives for Changing Call Forwarding
Returning to OVMD in general and it is possible to send a second ISD message to the VLR, for modifying any forwarding information the roamer currently has. For this step, there are 3 alternatives, as described in the following three embodiments:
1. Reference is now made to
2. Reference is now made to
3. Reference is now made to
However the installation of an SRM is itself complicated, and therefore the SRM embodiment is preferably retained for cases in which an SRM is already installed on site.
Signaling Relay Module
First of all it is desirable to say a few words about the signaling relay module, or SRM. An SRM is a signaling platform that is connected to the SS7 telephone signaling network at a given point. When connected it controls the SS7 traffic, generally consisting of GSM MAP messages, at that point, with the ability to modify signaling transactions or relay them with no modification. The SRM can be used to implement some of the optional voicemail deposit embodiments that will be described below.
There are two methods for integrating a signaling relay into the network: (a) transparently, as shown in
The transparent option, illustrated in
With reference now to
In the service node method, an originating node 106 originates a transaction, which passes initially to GMSC 108. Transactions reaching the GMSC 108 are now either routed via a first branch to SRM 110 by the GMSC, or via a second branch to destination mode 112. Transactions diverted to the SRM 110 instead of to the destination node 112 may later be routed later by the SRM to the destination node.
The above-described embodiments deal with the issue of obviating the trombone. In the following the issue of transferring call control data such as the telephone number of the calling party is considered in greater detail.
It is the intention of the present embodiments to provide roamers with the same caller identification capabilities that exist in domestic networks. When a roamer receives a call, the CLI in most cases is lost on the way, thus resulting in an unidentified call. If the call was not answered then the handset displays a missed call notification without a CU or with a meaningless CLI (i.e. “0001200”).
Roamers without voicemail have no other way of retrieving the caller ID for missed calls, only by receiving Who Called for Roamers SMS notification.
Reference is now made to
As shown in
The WHCfR application preferably identifies the user location changes, and creates a mapping of MSISDN
Any correlation between MSISDN
Every unanswered call (REL without ANM) may tier be defined as a WHCfR event. The unanswered call may be any of No Reply (no answer), Unreachable (page fault), and Busy.
The WHCfR can then monitor both outgoing and incoming calls on the international link to try and find a correlation with the calls that where forwarded back to the home network (to the Voicemail or to WHC local).
If a correlation is found it means that the voicemail or WHC local system can handle the Who Called notification and no WHCfR action is needed.
The decision whether to send a notification or not may be made by matching of the information elements or table 6 in the ISUP messages:
Preferably, there is provided an option not to send WHCfR events for specific destinations in dependence on the release cause, thus No Reply, Busy, Unreachable, or in accordance with other factors such as Mobile Country Code and Mobile Network Code or any combination of the above. Such an option may prevent double notification for destinations with guaranteed CLI delivery.
It is noted in this context that although CLIP is available with several operators, in the Busy and Unreachable situations, the handset doesn't display the missed calls in any event. Specifically these cases makes WHCfR valuable.
WHCfR events are typically reported to the WHC application server over SNAP.
The WHCfR preferably passes the following fields (via SNAP) to WHC application:
The WHCfR application may use calling or A party CLIR information. Furthermore if the A party has its CLIR set to restricted—no WHCfR event is preferably issued.
Calls that have been answered by a network prompt (ANM with NO CHARGE indication) from the visited network are preferably considered as NOT answered calls and a WHCfR event is preferably sent.
If an ANM is received without any charging indication then the event is treated as a normal ANM with charge.
In some cases an ISUP RELease message may not contain the actual release cause but a generic value. Such a case has been discussed above and need not limit the behavior of the WHCfR system.
In case of a failure (EP host by name, HTTP request, etc. . . . ) in sending a WHCfR event the WHCfR application typically retries sending. Retry logic is set by a SNAP_NUMBER_OF_RETRIES parameter and a SNAP_RETRY_INTERVAL parameter.
Reference is now made to
Following are the service limitations where handling extreme cases:
One limitation is that the WHCfR is liable to send a notification even if the call actually was answered by the called or B party, but with very short duration.
This case, known as a slam down, can happen due to lack of out/in call correlation, because the decision as to whether there is a “slam down” is based on a Timer (T1).
In cases of a short conversation WHCfR may decide that it is dealing with a slam down without correlation and send an event even though the B party has answered and did not actually miss the call.
Another limitation is that no WHCfR event may be triggered if the Voicemail Deposit lacks a CLI.
There may be cases where a voicemail is deposited but the voicemail notification has no caller ID. In such a case the WHCfR is not aware of the voicemail deposits being made and hence cannot react to the CLI deposits scenarios. In such a case no WHCfR notification is made.
The system is for use without restriction to the kind of networks. Nevertheless the present embodiments especially concentrate on the network types given in Table 7, in order of priority:
Because the system monitors all outgoing calls to roamers, the termination reason does not change the traffic capacity for the system.
For Example; On a 5,000,000 subscribers' network the traffic calculation is: 5,000,000×5%×2/10=50,000 BHCA per system.
As caller-ID is not available in most cases while roaming, roaming subscribers tend to eider shut off the handset or not to answer calls (or at least some of the calls) especially when they are engaged in e.g. business meeting. For example, handsets may be shut off due to different time-zones (roamer is sleeping).
Such a situation causes loss of revenue to the HPMN operator in all cases and to the VPMN operator in some cases, assuming that Optimal Routing is not implemented.
MCN can partially solve this problem: roamers who do not answer calls are able to receive an SMS with the details of the calling patty and therefore will try to get in contact with those who they want to.
MCN is becoming very popular in the local market. One example of such a product for the local market is the Converse Who Called service. Note that in the local market the only applicable case is the handset-off case since caller-ID (CLI) is available to an open handset. That is to say, as long as the telephone was switched on at the time the call was received, the calling number is saved for future reference. If the telephone was not switched on then an SMS arriving later with the details is valuable. However in the International context, the caller ID is rarely passed on, and thus even if the roamer's phone was switched on at the time, a subsequently received SMS with the caller details would be helpful.
Missed Call Notification is thus a valuable service for outbound roaming subscribers. If the phone is off/busy or the traveler simply does not answer a call, the application automatically sends an SMS to the roamer indicating the missed call event along with its details: caller ID, time and date of call.
With better control of incoming calls, roamers are more likely to return calls or send SMS messages, thus increasing network traffic and operator revenues.
Such a missed call notification may be provided as a default to all outbound roamers. However, some operators may wish to provide it on a subscription based approach.
The MCN preferably detects an unanswered mobile terminated call to an outbound roamer, in any of the ways outlined in the preceding embodiments.
If the MSC supplies the B-party's MSISDN then the MSISDN can be used as the address to send the SMS.
If the MSC does not supply the MSISDN then the MSISDN has to be obtained using other means, for example real-time probing as with the OVMD embodiment above.
Upon detection of an unanswered call the missed call notification or MCN involves the following:
The skilled person will also wish to support the case of no call forwarding.
The MCN preferably incorporates detection of a mobile terminated call to an outbound roamer that was either forwarded to an FTN (e.g. a voicemail service) in the HPMN or released due to non forwarding settings by the called party.
Upon detection of the forwarded call the MCN involves the following:
Rules such as the following may be applied.
If the roamer has forwarding settings to the VMS then either:
Missed Call Notification (MCN) Technical Solutions
There are 2 preferred solutions to implement an MCN service:
This solution is based on a combination of MAP & ISUP monitoring and an active HLR modification process.
In this case the probes are sufficient to provide solution.
Reference is now made to
In the case of HLR modification, the international gateway (I/G), using call control server (CCS), changes the call forwarding conditions in the HLR as follows:
Reference is now made to
Reference is now made to
This second solution is based on an additional valid OVMD infrastructure already implemented at the operator's network. In addition an HLR modification process is added to provide a complete solution. The OVMD in the present solution allows late call forwarding CF and missed call notification MCN in addition to optima routing. The HLR Modification also allows early call forwarding and missed call notification.
This solution uses the OVMD infrastructure to control missed calls to subscribers while roaming, and hereinbelow we explain the MCN interaction regardless of OVMD optimization.
In this case the I/G 150, using call control server (CCS), changes the CF conditions in the HLR as follows:
Reference is now made to
There are two alternative technical solutions for the Optimal Voicemail Deposit, depending on the host network as explained above.
Following is a description of the two options.
Based on IN architecture, the IntelliGate controls calls delivered to outbound roaming subscribers. This solution fits to networks that are already IN or CAMEL ready and/or networks that experience a relatively high outbound roaming traffic.
Using CS1 or CAP protocols, call control is performed using a combination of Trigger Detection Points and Event Detection points.
In particular cases, such as non-IN network environment and/or relatively low outbound roaming traffic; call control is performed using ISUP signaling. When a call is not completed—subscriber does not answer or is not available—the IntelliGate is triggered to directly route the call to the called party's voicemail system using only HMPN resources, along with the original called number, as if it were a local call in the home network.
Call control does not necessarily connecting the IntelliGate to the network via voice channels. Rather signaling links are only required to convey the ISUP signaling. This inter-connection is achieved by utilizing a ‘Loop-Back’ technique on the MSC.
In some cases the technical solution must support deactivation of the existing forwarding settings of the outbound roamer as soon as he/she registers at a foreign VLR.
However, the operator may choose to either do the deactivation by itself (e.g. using an HLR script) or give up doing any such deactivation. The delivered solution is adapted to the decision taken.
Reference is now made to
Reference is now made to
Using the generic MT (Mobile Terminated) control according to the above embodiments, it is possible to provide the following customized features as desired:
Specialized Unavailability Message
The present embodiments are able to analyze the return codes from the telephony call, and act accordingly, thus:
It is expected that during the life of this patent many relevant cellular networking devices and systems will be developed and the scopes of the terms herein, particularly, but not exclusively of the terms “Intelligent Network” “ISUP”, “Voicemail”, “HLR”, “VLR”, “call forwarding”, “roaming”, “Intelligent Gateway”, “probe”, “SS7”, “MSC”, “GMSC” and “call forwarding”; is intended to include all such new technologies a priori.
It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable subcombination.
Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.