United States Patent (19)
`Alperovich et al.
`
`54
`
`PROVIDING LOCATION-BASED CALL
`FORWARDING WITHIN A MOBILE
`TELECOMMUNICATIONS NETWORK
`
`(75)
`
`73)
`
`Inventors: Vladimir Alperovich, Dallas; Eric
`Valentine, Plano, both of Tex.
`Assignee: Ericsson Inc., Research Triangle Park,
`N.C.
`
`Appl. No.: 08/766,296
`Filed:
`Dec. 13, 1996
`Int. Cl. ..................................................... H04Q 7/22
`U.S. Cl. ............................................. 455/417; 455/414
`Field of Search ..................................... 455/417, 456,
`455/445, 432, 414
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`5,497,412 3/1996 Lannen et al. .......................... 455/432
`5,504.804 4/1996 Widmarket al.
`... 455/414
`5,557.655 9/1996 Lantto ..............
`... 455/432
`5,689,548 11/1997 Maupin et al. ......................... 455/404
`
`
`
`USOO5978673A
`Patent Number:
`11
`(45) Date of Patent:
`
`5,978,673
`Nov. 2, 1999
`
`Primary Examiner Dwayne D. Bost
`Assistant Examiner Myron K. Wyche
`Attorney, Agent, or Firm Jenkens & Gilchrist
`57
`ABSTRACT
`Call forwarding data, including forward to numbers for a
`particular mobile Station are correlated with a particular
`Service area and stored at a home location register (HLR)
`associated with that particular mobile station. Whenever the
`mobile station travels into a mobile Switching center (MSC)
`Serving that particular Service area, the MSC performs a
`location update with the HLR. A location update Signal
`further includes data representing the identity of the Service
`area currently Serving the mobile Station. Upon receiving the
`location update signal from the serving MSC, the HLR
`analyzes the received data to determine the identity of the
`Service area currently Serving the mobile Station and
`retrieves the call forwarding data associated with that par
`ticular Service area. The retrieved call forwarding data are
`then analyzed to determine whether the forward to numbers
`are located in the current Service area for the mobile Station
`and, if so, transmitted back to the serving MSC in order to
`provide location-based call forwarding to the roaming
`mobile Station.
`
`34 Claims, 6 Drawing Sheets
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`Page 1 of 13
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`Nov.2, 1999
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`Sheet 5 of 6
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`PLMN
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`Sheet 6 of 6
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`430
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`MS performs a location update
`with the Servino MSC
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`The SEYng MSC receives an IMSI number
`from MS Ond determines the HLR
`
`HLR receives the location update signal and
`determines the Service Oreo in which the MS is
`currently located
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`Retrieve predetermined forward to numbers
`based upon location of determined service Oreo
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`Transmit predetermined forwgrd to numbers
`to Servind MSC
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`Store received predetermined forword to
`numbers in OSSocioted WLR
`
`Determine whether the forward to numbers
`ore currently located within the service Oreo
`serving the mobile station
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`Exclude forword numbers not currently located
`in the service ared from being utilized to
`provide call forwarding to the mobile stotion
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`Provide coll forwarding to MS utilizing
`received predetermined forward to numbers
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`FIG. 6
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`1
`PROVIDING LOCATION-BASED CALL
`FORWARDING WITHIN A MOBILE
`TELECOMMUNICATIONS NETWORK
`
`BACKGROUND OF THE INVENTION
`1. Technical Field of the Invention
`The present invention relates to a telecommunications
`network and, in particular, to the provision of location-based
`call forwarding within a Public Land Mobile Network
`(PLMN).
`2. Description of Related Art
`With the advent and development of mobile telecommu
`nications Systems, telecommunications users are no longer
`physically bound to wireline terminals or fixed locations for
`telecommunications network communications. Using the
`added capabilities of roaming and interoffice handoffs,
`mobile Subscribers may travel between multiple Public Land
`Mobile Networks (PLMNs) utilizing the same telephone
`number and the same mobile Station to originate outgoing
`calls and to receive incoming calls. Thus, a mobile Sub
`Scriber may acceSS telecommunications Service from mul
`tiple locations utilizing multiple Service providers with any
`incurred fees being charged to a Single Subscription.
`Additionally, parties originating a call do not necessarily
`have to know where the desired mobile subscriber is physi
`cally located in order to properly route and to establish a call
`connection. Data Signals between Visitor location registers
`(VLRs) and a home location register (HLR) automatically
`update and Store Subscriber information enabling the net
`work to reroute incoming calls to the appropriate mobile
`Switching center (MSC) serving the roaming mobile Sub
`scriber. Furthermore, regardless of which MSC is currently
`serving the mobile station, the VLR associated with the
`serving MSC communicates with the HLR assigned to the
`mobile Station to retrieve the requisite Subscriber data,
`including Subscriber feature data and billing data, and pro
`vide uniform mobile service to the mobile station.
`However, Such uniformity in Service is not always desir
`able for a subscriber. For example, such uniformity in
`Service to a roaming mobile Station is not desirable where a
`caller desires not So much to contact a particular mobile
`Subscriber, but to contact a mobile Subscriber if that mobile
`Subscriber is within a certain geographical location. For
`example, where the mobile Subscriber is a Service provider
`(e.g., maintenance provider for office equipment) and the
`caller desires to initiate a Service call, it is only desirable to
`reach the mobile Subscriber when that mobile Subscriber is
`in the caller's general geographical location. It provides the
`caller with no benefit to have his or her call forwarded to a
`maintenance person when that perSon is traveling outside his
`or her normal geographical area. Additionally, it is desirable
`for Such a Service provider to have only a Single or very few
`Service numbers available to its customers.
`A much more desirable system would allow a mobile
`telecommunication System to forward to one of a predeter
`mined Set group of mobile Stations based upon the location
`of mobile Subscriber called.
`Accordingly, there is a need for a mechanism to enable the
`mobile telecommunications network to provide Service area
`call forwarding features to mobile Subscribers, enabling
`mobile Subscribers to maximize desired use of the feature
`and minimized unproductive use of Such features.
`SUMMARY OF THE INVENTION
`The present invention discloses a method and System for
`providing location-based call forwarding features to a
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`mobile Station. Using the present invention method and
`System, when a call enters the gateway mobile Switching
`center (GMSC), the GMSC communicates with a home
`location register (HLR) associated with the mobile station to
`determine the MSC currently serving the mobile station. The
`HLR is periodically provided with a location update Signal
`including data identifying the Service area currently Serving
`the mobile station. By analyzing the received data, the HLR
`is able to determine the identity of the Service area currently
`Serving the mobile Station.
`The service area determined and analyzed by the HLR
`includes a Public Land Mobile Network (PLMN) area
`currently covering the mobile Station. The Service area may
`also include an MSC coverage area currently covering the
`mobile Station. Alternatively, the Service area may also
`include a location area within a particular Serving MSC
`coverage area. For the HLR to properly analyze and deter
`mine the location area, the location update Signal transmitted
`by the serving MSC further includes data representing the
`location area currently Serving the mobile Station.
`Once the general location of the mobile Station is known,
`the HLR, finding the mobile station is busy, forwards the
`incoming call to one of a number of predetermined forward
`to numbers based upon location.
`BRIEF DESCRIPTION OF THE DRAWINGS
`A more complete understanding of the method and appa
`ratus of the present invention may be had by reference to the
`following detailed description when taken in conjunction
`with the accompanying drawings wherein:
`FIG. 1 is a block diagram illustrating a public land mobile
`network (PLMN) interfacing with a mobile station and a
`public Switched telephone network (PSTN);
`FIG. 2 is a block diagram illustrating a serving MSC
`performing a location update with a home location register
`(HLR);
`FIG. 3 is a block diagram illustrating the forwarding of an
`incoming call by a Serving MSC to a designated forward
`to-number in a conventional System;
`FIG. 4 is a block diagram illustrating the HLR associated
`with a particular mobile Station providing location-based
`call forward data to a visited MSC;
`FIG. 5 is a block diagram illustrating a SLP providing
`location-based call forward data to a visited MSC; and
`FIG. 6 is a flowchart illustrating the exemplary steps
`performed within a mobile telecommunications network for
`providing the location-based call forward feature of the
`present invention.
`DETAILED DESCRIPTION OF THE DRAWINGS
`FIG. 1 shows a block diagram of a telecommunications
`System in which the present invention method and System
`may be implemented. A public land mobile network
`(PLMN) 10a or 10b comprises a gateway mobile switching
`center (GMSC) 20, at least one mobile switching center
`(MSC) 30, a home location register (HLR) 40, a visiting
`location register (VLR) 50 and a base station controller
`(BSC) 60 associated with each MSC 30. The PLMN 10a or
`10b is used to communicate with a mobile station 70 and is
`also linked with a public Switched telephone network
`(PSTN) 80 to provide communications with other telephone
`subscribers. The BSC 60 is linked with the MSC 30 using
`digital communications link 90 and communicates with the
`mobile station 70 via a radio channel 100. The HLR 40
`comprises a database containing information about "home’
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`Subscribers, their Services and their locations. For purposes
`of this application, “home” is defined as the PLMN service
`provider with which the subscriber has their agreement. The
`VLR 50 comprises a database containing information about
`“visiting” subscribers, their services and their location. For
`purposes of this application, “visiting is defined as the
`Situation when a mobile Station has traveled out of its home
`PLMN and is being serviced by a MSC other than their
`home MSC.
`When the mobile station 60 travels out of its home PLMN
`10a and into a visited PLMN 10b, a visited MSC 30
`communicates with the HLR 40 within the home PLMN 10a
`to authenticate and Verify telecommunications Service for
`the visiting mobile station 70 and to retrieve pertinent
`Subscriber information from the home HLR 40. Once
`authenticated, the mobile Station 60 is registered as a "roam
`ing” Subscriber and is provided with telecommunications
`Service.
`A telecommunications terminal, Such as a wireline termi
`nal 110, originates an outgoing call directed towards the
`mobile station 70 by dialing a directory number, such as a
`Mobile Subscriber Integrated Service Digital Network
`(MSISDN) number, associated with that mobile station 70.
`A call setup signal is initially routed from the PSTN 80 to the
`GMSC 20 serving the home PLMN 10a for the mobile
`station 70. The home GMSC 20 queries the home HLR 40
`in response to the call Setup signal to determine the exact
`location of the mobile Station 70. The home GMSC 20
`accomplishes this by Sending a signal requesting a routing
`instruction to the home HLR 40 via signal link 120. The
`home HLR 40 determines the identity of the MSC 30
`currently serving the mobile station 70 and further transmits
`a signal requesting a roaming number to the Serving MSC 30
`via signal link 130. The serving MSC 30 verifies that the
`mobile station 70 is currently within its service area and
`returns the roaming number to the home HLR 40 via signal
`link 140. The home HLR 40, in turn, forwards the received
`roaming number to the GMSC 20. The GMSC 20, utilizing
`the new roaming number, reroutes the received call Setup
`Signal, Such as an Initial Address Message (IAM), to the
`specified MSC 30 via signal link 160. The serving MSC 40
`then pages the mobile station 70 over a page channel (PCH)
`and, upon receiving a response therefrom, establishes a
`speech connection with the mobile station 70 over a traffic
`channel (TCH).
`Accordingly, for the mobile telecommunications network
`to properly provide mobile Service towards a particular
`mobile Station, certain information needs to be periodically
`updated. The HLR 40 associated with the mobile station 70
`must be updated with the identity of the MSC 30 currently
`serving the mobile station 70. This information is later
`utilized by the GMSC 20 to reroute incoming calls to the
`appropriate serving MSC 30. The serving MSC 30 and its
`associated VLR 50 must also be updated with the requisite
`Subscriber data to provide appropriate mobile Service to the
`mobile station 70. Each time a call is originated from or
`terminated towards the mobile station 70, the serving MSC
`30 cannot afford to initiate a communication with the HLR
`40 associated with the mobile station 70 to exchange the
`necessary information. Accordingly, the serving MSC 30
`and the attached VLR 50 need to be updated with the
`necessary Subscriber data Specific to the Visiting mobile
`station 70 to properly service the mobile station 70. Such
`data include Subscriber feature preferences, billing account
`information, etc.
`In order for the mobile network to properly locate the
`called mobile station 70 and to reroute the incoming call to
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`the appropriate MSC 30, the home HLR 40 needs to keep
`track of the current location of the mobile station 70.
`Accordingly, reference is now made to FIG. 2 illustrating a
`serving MSC 30 performing a conventional location update
`with the HLR 40 associated with the mobile station 70.
`Whenever the mobile station 70 roams into one of the
`location areas being served by the MSC 30, the mobile
`station 70 attempts to register with the serving MSC 30 by
`transmitting an identification number, Such as an Interna
`tional Mobile Subscriber Identity (IMSI) number, associated
`with the mobile station 70 to the serving MSC 30 via the
`BSC 60.
`In order to authenticate the mobile station 70, the serving
`MSC 30 utilizes the received IMSI number to transmit a
`location update signal (signal 170) to the HLR 40 associated
`with the roaming mobile station 70. By transmitting a
`Signaling Connection Control Point (SCCP) based Signal
`ing System No. 7 (SS7) signal using the received IMSI
`number as the SCCP destination address enables the con
`necting telecommunications network to route the transmit
`ted signal from the serving MSC 30 to the HLR 40. The
`HLR 40 associated with the roaming mobile station 70 then
`verifies the identity of the mobile station 70 and also updates
`its database to take note of the MSC currently serving the
`mobile station 70. Such information is later utilized by the
`HLR 40 to reroute incoming calls. The HLR 40 further
`retrieves Subscriber data associated with the mobile station
`70 and communicates the retrieved data to the serving MSC
`performing the location update (signal 180). The transmitted
`data are then utilized by the serving MSC 30 to provide
`mobile service to the roaming mobile station 70. Such
`Subscriber data includes forward-to-numbers for call for
`warding features, billing data, long distance carrier data, etc.
`Upon receiving the transmitted Subscriber data, the Serv
`ing MSC 30 stores the data at the attached VLR 50.
`Thereinafter, mobile service in accordance with the received
`subscriber data is provided to the roaming mobile station 70.
`By requiring the serving MSC 30 to retrieve Subscriber data
`from the HLR 40 specifically associated with the mobile
`station 70, regardless of which MSC is serving the mobile
`station 70, the same subscriber feature data, billing
`Subscription, and other user defined information are utilized
`to provide uniform mobile service to the mobile station 70.
`However, as previously discussed herein, Such uniformity
`in Service is not always desirable. Reference is made again
`to FIGS. 2 and 3 to illustrate the forwarding of an incoming
`call by a conventional System. Upon performing a location
`update with the home HLR 40, the serving VLR 50 is
`updated with the requisite Subscriber data including the
`forward-to-number for the prior art Call Forward on Busy
`(CFB) subscriber feature. Subsequently, another telecom
`munications terminal, Such as the wireline terminal 110,
`dials the MSISDN number associated with the mobile
`Station 70 and originates a call connection. A generated call
`Setup message, Such as an IAM Signal, is first received by the
`serving GMSC 20 associated with the home PLMN 10a for
`the mobile station 70. The GMSC 20 then transmits a signal
`requesting routing instruction to the HLR 40 associated with
`the received MSISDN number (signal 120). The HLR 40, by
`retrieving the network address of the serving MSC 30
`received during the last location update, also sends a signal
`requesting a roaming number to the Serving MSC 30 (signal
`130). The serving MSC 30 returns a roaming number to the
`HLR 40 (signal 140) and the HLR 40, in turn, forwards the
`received roaming number back to the GMSC 20 (signal
`150). Utilizing the received roaming number, the incoming
`call is properly rerouted to the serving MSC 30. The serving
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`MSC 30 next determines that the mobile station 70 is already
`in Speech connection with another terminal and ascertains
`whether the mobile station 70 has one of the call forwarding
`features activated. Upon determining that the mobile Station
`70 has CFB activated, the serving MSC 30 retrieves the
`previously stored forward-to-number from the VLR 50 and
`accordingly forwards the received incoming call to the
`Specified forward to number. As an illustration, a call
`connection between the wireline terminal 110 and a first
`telecommunications terminal 200 is accordingly established.
`Such a call connection is inefficient and wasteful if the
`first telecommunications terminal 200 is located outside
`LATA (LATA-A) from where the call was intended. As
`previously discussed, in the example of a Service call request
`it is of little or no use that the call was forwarded to a
`terminal or mobile Station outside the appropriate geographi
`cal location Since Service is needed within that geographical
`area. As a result, the mobile Subscriber has to pay for the
`long distance charges incurred for rerouting the call con
`nection back to the first telecommunications terminal 200
`and Still has not had the information delivered to appropriate
`geographical area. In all likelihood, the first telecommuni
`cations terminal 200 will now have to generate a call (and
`probably incur long distance charges) back to the originating
`geographical area to get the Service request filled.
`It would therefore be advantageous for the mobile Sub
`scriber to have the ability to have calls directed to a mobile
`Station target forwarded to one of a predetermined set of
`forward to numbers within the PLMN of the called mobile
`station so that when the mobile station 70 is busy or
`otherwise not receiving calls, the calls are routed to a
`number on the forward to list. By forwarding an incoming
`call to a mobile station to another telecommunications
`terminal within the targeted PLMN when the called mobile
`Station is busy, no long distance charges are incurred by the
`mobile station 70 and the calls are received by a mobile
`station associated with the targeted PLMN, the area in which
`action is desired.
`Accordingly, there is a need for a mechanism to enable the
`mobile telecommunications network to Selectively forward a
`call to a predetermined list of numbers within a PLMN based
`upon the location of the mobile Station.
`FIG. 4 is a block diagram illustrating the HLR 40 asso
`ciated with the mobile station 70 providing location based
`call forwarding. Whenever the mobile station 70 is turned on
`or travels into a new location area, the mobile station 70
`performs a location update procedure with the Serving MSC
`30. The serving MSC 30, in turn, transmits a location update
`signal to the HLR 40 associated with the registering mobile
`station 70 (signal 170). While transmitting the location
`update signal, the serving MSC 30 further includes data
`representing the Service area currently Serving the mobile
`station 70. In case the mobile network wishes to provide
`PLMN or MSC service area dependent subscriber data, a
`network address representing the serving MSC 30 is trans
`mitted to the HLR 40. By analyzing the network address, for
`example, representing the serving MSC 30, the HLR 40 is
`able to determine the identity of the PLMN or MSC cover
`age area Serving the mobile Station. In case the mobile
`network wishes to provide the location-based call forward
`ing feature of the present invention, the location update
`Signal further needs to include data representing the Serving
`location area, Such as a location area identity (LAI).
`Upon receiving the location update Signal from the Serv
`ing MSC 30, an application module 210 associated with the
`HLR 40 analyzes the data representing the service area
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`currently Serving the mobile Station and accordingly
`retrieves the predetermined forward to numbers associated
`with that service area from the data register 220. As
`described above, in case the analyzed Service area is not
`included as one of the pre-stored Service areas within the
`data register 220, the master Service area data are instead
`retrieved.
`Using a signal, such as a Mobile Application Part (MAP)
`based Insert Subscriber Data signal, the HLR 40 commu
`nicates the retrieved data to the serving MSC 30 (signal
`180). The serving MSC 30 then stores the received call
`forward data to the attached VLR 50. Thereinafter, the stored
`subscriber data are utilized by the serving MSC 30 to
`provide mobile service to the mobile station 70. As an
`illustration, one or more predetermined forward-to-numbers
`for CFB representing a local terminal within the serving
`service area are retrieved by the HLR 40 and communicated
`back to the MSC 30 and VLR 50. Subsequently, all incom
`ing calls received by the serving MSC 30 while the mobile
`station 70 is busy are forwarded by the serving MSC 30 to
`one of the predetermined forward-to-numbers so that the call
`is completed with a mobile station or terminal within the
`desired geographical location.
`In case the mobile station 70 roams into a different service
`area, another Set of predetermined forward to numbers is
`again retrieved for this new Service area and accordingly
`provided to the new MSC.
`Referring now to FIG. 5, there is shown an alternate
`embodiment of the location-based call forwarding feature of
`the present invention. More specifically, FIG. 5 illustrates an
`embodiment of the present invention implemented within an
`intelligent network (IN) or an advanced intelligent network
`(AIN). The PLMN 250 is used to communicate with mobile
`station 255 and is also linked with a public Switched
`telephone network (PSTN) 260 to provide communications
`with other telephone subscribers 280. Within the PSTN 260,
`service switching point (SSP) 265 is connected to service
`control point (SCP) 267 via lines 285 and 290. In this
`embodiment of the location-based call forwarding feature of
`the present invention, the SCP 267 includes an application
`module 300 including a data register 305 having the prede
`termined list of forward to numbers for the mobile station
`310. It is understood that line 285 and line 290 may actually
`represent a plurality of lines with an IN or AIN.
`In use, if mobile station 255 is determined to be busy or
`unreachable, the serving MSC 315 informs SSP 265 of this
`state along with the location of the mobile station 255. The
`SSP 265 in turn informs the SCP 267 of this information.
`The SCP 267, utilizing the application module 300 and data
`register 305, determines the appropriate forward to number
`(e.g., based upon the location of the mobile station 255) and
`informs the SSP 265 to reroute the call to the appropriate
`forward to number. Alternately, the MSC 315 could attempt
`to complete the call setup without first querying the SSP265.
`Again, if the mobile station 255 is busy or otherwise
`unreachable, the MSC 315 would then inform the SSP 265
`of the unreachable state and the location of the mobile
`station 255. The SSP265 would, in turn, inform the SCP267
`of this information and the SCP 267 would determine the
`appropriate forward to number based upon the location of
`the mobile station 255 and provide the SSP 265 with this
`information So that the call could be appropriately rerouted.
`In the PLMN context, a Mobile Application Part (MAP)
`based Insert Subscriber Data Signal is used to communi
`cate information between the HLR and the MSC. In the
`PSTN context, a Transaction Capability Application Part
`(TCAP) signal or Intelligent Network Application Part
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`(INAP) signal is used to communicate information between
`the SSP 265 and the SCP 267.
`FIG. 6 is a flowchart illustrating the exemplary steps
`performed within a mobile telecommunications network for
`providing the location-based call forwarding feature of the
`present invention. AS described above, whenever a mobile
`Station travels into a new location area, the mobile Station
`performs a location update with the serving MSC at step 400
`and transmits its International Mobile Subscriber Identity
`(IMSI) number. By analyzing the received IMSI number, the
`serving MSC determines the identity of the HLR associated
`with the registering mobile station at step 410. The serving
`MSC, in turn, performs a location update with the HLR
`associated with the mobile station to inform the HLR of the
`mobile Station's new location and to retrieve the requisite
`subscriber data at step 420. The serving MSC further trans
`mits data representing the Service area currently Serving the
`mobile Station. If the Service area includes the Serving
`PLMN or MSC coverage area, the network address present
`ing the serving MSC Suffices. If the service area includes the
`location area currently Serving the mobile Station, the
`address, Such as a location area identity (LAI) or cell
`identity, needs to be transmitted to the HLR.
`AS a result, the HLR receives the location update Signal
`from the serving MSC and determines the service area
`currently Serving the roaming mobile Station at Step 420.
`Utilizing the determined service area, the HLR retrieves the
`Subscriber data, including the location-based call forwarding
`data, correlated with the current Service area for the roaming
`mobile station at step 430. Using a MAP based Insert
`Subscriber Data signal, the HLR transmits the retrieved
`Subscriber data, including the Set of call forwarding data, to
`the serving MSC at step 440. Included in the call forwarding
`data received is a Set of predetermined forward to numbers
`previously selected by the mobile subscriber. Upon receiv
`ing the location-based forward to numbers from the HLR,
`the serving MSC stores the data at the attached VLR at step
`450. Thereinafter, utilizing the service area dependent Sub
`Scriber data, including the predetermined forward to
`numbers, provided by the HLR, the serving MSC provides
`mobile service to the roaming mobile station at step 460.
`In another embodiment, the method further includes two
`steps which occur after step 450 and before step 460. The
`additional Steps are: the Step of determining whether the
`forward to numbers are currently located within the current
`service area for the mobile station (step 455); and, the step
`of excluding those forward to numbers not currently located
`within the Service area Serving the mobile Station from being
`utilized to provide call forwarding service to the mobile
`station (step 457).
`50
`In yet another embodiment, in step 457 forward to num
`bers can be excluded based upon factors other than current
`location. For example, a time-based System could be
`employed to only use forward to numbers during certain
`time periods (e.g., weekends, between 9 a.m. and 5 p.m.).
`Forward to numbers could be subject to any number of
`criteria before being utilized in step 460 to provide the
`mobile station with call forwarding.
`Finally, in another embodiment, steps 430 through 460 are
`Slightly modified in that the application module including
`the data register of the predetermined forward to numbers is
`associated with a SCP versus a HLR. A SSP within an IN or
`AIN is contacted by the serving MSC and, in conjunction
`with the SCP, the SSP reroutes calls according to the
`predetermined forward to numbers.
`Although a preferred embodiment of the method and
`apparatus of the present invention has been illustrated in the
`
`8
`accompanying Drawings and described in the foregoing
`Detailed Description, it will be understood that the invention
`is not limited to the embodiment disclosed, but is capable of
`numerous rearrangements, modifications and Substitutions
`without departing from the Spirit of the invention as Set forth
`and defined by the following claims.
`What is claimed is:
`1. A method for providing location-based call forwarding
`data to a mobile Switching center (MSC) serving a mobile
`Station within a mobile telecommunications network, Said
`method comprising the Steps of
`receiving a signal at a home location register (HLR)
`indicating that Said mobile Station is currently within a
`Service area associated with said MSC;
`retrieving a predetermined set of call forwarding data
`designated for use within the Service area within which
`the mobile Station is currently located; and
`providing Said retrieved predetermined Set of call for
`warding data from said HLR to said MSC for call
`forwarding use when said mobile Station is located
`within Said Service area.
`2. The method of claim 1 wherein said step of receiving
`Said Signal at Said HLR further includes the Step of receiving
`a Mobile Application Part (MAP) based location update
`Signal from Said MSC, Said location update Signal further
`including a network address representing Said MSC.
`3. The method of claim 2 further comprising the step of
`analyzing Said network address representing Said MSC to
`determine Said location of Said Service area.
`4. The method of claim 1 wherein said service area
`comprises a Public Land Mobile Network (PLMN) area.
`5. The method of claim 1 wherein said service area
`comprises a MSC coverage area.
`6. The method of claim 1 wherein said signal received by
`Said HLR further includes data identifying a location area
`where said mobile Station is currently located, and Said
`Service area comprises Said location area currently Serving
`Said mobile Station.
`7. The method of claim 1, wherein said retrieved prede
`termined set of call forwarding data comprises a Selected
`one of a plurality of Sets of forward-to-numbers and Said Step
`of poroviding further includes the Step of determining which
`set of forward-to-numbers should be utilized for said service
`aca.
`8. The method of claim 7, wherein said step of providing
`further includes the Step of determining whether any of Said
`determined set of forward-to-numbers are currently located
`within Said Service area.
`9. The method of claim 8, wherein said step of providing
`further includes the Step of excluding, from Said determined
`Set, forward-to-numbers determined to not currently be
`located within Said Service area.
`10. A method for retrieving location-based call forward
`ing Subsc