Abstract:
Systems and methods for enforcing calling restrictions are provided. When a first and second communication station are located in different domains, calling restrictions for a first communication station can be based on a current geographic location of the second communication station. The calling restrictions can be enforced independent of an address/identifier of the first or second communication station. The calling restrictions can be based on the current geographic locations of the first and second communication stations and the allowed geographic area of the first communication station.

Description:
BACKGROUND OF THE INVENTION 
     Communication network operators enforce a variety of calling restrictions on subscribers. One of the most common calling restrictions is to limit a caller to initiating only local calls because communication network operators typically incur additional fees to carry non-local calls. Subscribers that do not wish to incur additional fees for such calls can have their account restricted from making long distance calls. 
     Conventional systems enforce these long distance calling restrictions based on some portion of the calling and called party&#39;s numbers. Calls in which the calling and called party numbers have different area codes are typically restricted based on this difference in area codes. Some calls made within the same area code are not considered local calls, and incur additional fees. These types of calls can be restricted based upon the local exchanges of the calling and called party&#39;s numbers (i.e., the first three digits of XXX-XXXX). 
     SUMMARY OF THE INVENTION 
     Although restricting calls based on the calling and called party&#39;s numbers may be appropriate for wireline communication networks, this technique may not adequately address issues faced by wireless network operators. For example, assume that a wireless communication station has a telephone number associated with a first geographic area. When this wireless communication station is located in a second geographical area and initiates a call to a second wireless communication station located in the second geographical area, conventional communication networks would treat this call as a long-distance call. This call treatment would occur even if the two wireless communication stations are located within a few feet of each other. Accordingly, the present invention enforces calling restrictions based on the geographic location of the called party, and in some embodiments also based on the current geographic location of the calling party. 
     An additional difficulty arises when attempting to enforce the inventive geographic calling restrictions when the calling and called parties are located in different networks. When call restrictions are based on the telephone numbers of the calling and called parties, and when these parties are located in different networks, the calling restrictions can easily be enforced because the originating network has all of the information necessary for enforcing the restrictions (i.e., the calling and called party&#39;s telephone numbers). When implementing the inventive geographic-based calling restrictions between calling and called parties located in different networks, the originating network may not have the ability to determine the current geographic location of the called party. Accordingly, exemplary embodiments of the present invention provide a number of different systems and methods for obtaining the called party&#39;s current geographic location and enforcing the calling party&#39;s call restrictions. 
     Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         FIG. 1  is a block diagram illustrating an exemplary system in accordance with the present invention; 
         FIGS. 2   a - 2   c  are block diagrams illustrating exemplary systems in accordance with the present invention; and 
         FIG. 3  is a flow diagram of an exemplary method in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is a block diagram illustrating an exemplary system in accordance with the present invention. The system includes domains  105  and  110 , which have at least some overlap in geographical coverage. The domains may be under the administrative jurisdiction of a single entity or they may be controlled by different administrative entities. Domains  105  and  110  can be different networks, different portions of the same network and/or different portions of different networks. Domain  105  supports communication station  115  and domain  110  supports communication station  120 . Domain  105  includes call processing element  125  coupled to location register  130  and gateway  135 . Domain  110  includes call processing element  140  coupled to location register  145  and gateway  150 . Inter-domain element  155  couples domains  105  and  110  via gateways  135  and  150 . 
     Communication domains  105  and  110  can operate as any type of communication network, such as an iDEN network, QChat network, CDMA-based network, TDMA-based network, OFDM-based network (e.g., a WiFi- or WiMax-based network) and/or the like. Communication stations  115  and  120  can be any type of communication stations including a wireless telephone, personal digital assistant and/or the like. These communication stations can be arranged to conduct interconnect voice, dispatch voice and/or data communications. The dispatch communications can include push-to-talk, instant messaging or any other type of dispatch communications. The data communications can include voice over internet protocol (VoIP), electronic mail, paging, short messaging service (SMS), multimedia messaging service (MMS), peer-to-peer communications, application to person communication, application to application communications or any other data sharing type of communications. 
     Call processing elements  125  and  140  can be any type of call processing element including, but not limited to, a dispatch server and/or mobile switching center. Location registers  130  and  145  can be any type of location registers including, but not limited to, home location registers and/or visitor location registers. Although  FIG. 1  illustrates call processing elements as distinct from the location registers, they can be a single network element, such as a mobile switching center/visitor location register (MSC/VLR). Gateways  135  and  150  can be any type of gateway for handling calls between different domains or networks, and can, in some embodiments, perform signaling and media protocol conversion, in which case inter-domain element  155  may be omitted. Inter-domain element  155  can perform signaling and media protocol conversion between domains  105  and  110 . Although  FIG. 1  illustrates inter-domain element  155  as being coupled to only two domains, this element can be coupled to more than two domains. Although  FIG. 1  illustrates a single gateway for domain  105 , the domain can include more than one gateway, such as a separate gateway for each external domain. 
       FIGS. 2   a - 2   c  are block diagrams illustrating exemplary systems in accordance with the present invention. For ease of explanation and not limitation, the various network elements of  FIG. 1  are not illustrated in  FIGS. 2   a - 2   c . The calling location areas illustrated in  FIGS. 2   a - 2   c  can correspond to any type of geographic area, including, but not limited to, a town, city, county, state or the like. Additionally, the location areas can have arbitrary geographic areas not tied to particular governmentally defined areas and/or these location areas need not necessarily be contiguous. In the examples described below in connection with  FIGS. 2   a - 2   c , the call restriction is based solely on the callers current geographic location and the allowed geographic area defined by the originating domain. However, more or less factors can be employed for assessing calling restrictions. 
     In the system illustrated in  FIG. 2   a  domains  105  and  110  each include three calling location areas, which have the same geographic boundaries. Assume that communication station  115  is calling communication station  120 , and that location area  210  defines the allowed geographic area for communication station  115 . Because communication station  120  is located within the allowed geographic area for communication station  110  the call should not be restricted. Assume now that location area  208  is the “home” location area for communication station  115 , which is roaming in location area  210 . If communication station  115  is not restricted from initiating calls while roaming and if location area  210  is included in the allowed geographic area of communication station  115 , the call will not be restricted because communication station  120  is located in the allowed geographic area for communication station  115 . In this example, the call would not be restricted even if the calling numbers of communication stations  115  and  120  had different area codes or other regional identifiers of their calling numbers. 
     Referring now to  FIGS. 2   b  and  2   c , domains  105  and  110  have location areas with different geographic boundaries and location area  210  defines the allowed geographic area for communication station  115 . Domain  105  includes three location areas  208 ,  210  and  212  (delineated by solid lines), and domain  110  includes two location areas  214  and  216  (delineated by solid lines). The dashed lines in  FIGS. 2   b  and  2   c  illustrate how the boundaries of the location areas of domain  105  correspond to the location areas of domain  110 . Referring now to  FIG. 2   b , when communication station  115  initiates a call to communication station  120 , the call will not be restricted because communication station  120  is located in the allowed geographic area for communication station  115  (as defined by location area  210  of domain  105 ). In the system illustrated in  FIG. 2   c , however, the call from communication station  115  to communication station  120  will be restricted because communication station  120  is not located in the allowed geographic area for communication station  115  (as defined by location area  210  of domain  105 ). This call is restricted even though communication station  120  is in the same location area of domain  110  (i.e., location area  214 ) in both  FIGS. 2   b  and  2   c.    
       FIG. 3  is a flow diagram of an exemplary method in accordance with the present invention. The method of  FIG. 3  can be performed by a number of different elements in the system of  FIG. 1 , and this method will be initially described in connection with gateway  135 . When gateway  135  receives a call request from communication station  115  for communication station  120  (step  305 ), the gateway determines that calls for communication station  115  are subject to geographic calling restrictions (step  310 ). Gateway  135  can determine whether communication station  115  is subject to geographic calling restrictions based on an indication in the call request message or by accessing location register  130 . Gateway  135  also determines that communication station  120  is not located in domain  105  and the domain in which the communication station is located (step  315 ). The domain determination can be based on the calling number of communication station  120 . Because the communication station  120  can be a mobile station, the called number of communication station  120  only indicates its administrative domain, and not necessarily its current geographic area. 
     Gateway  135  then determines the current geographic location of and the allowed geographic area for communication station  115  (step  320 ). The current geographic location of communication station  115  can be provided to gateway  135  as a Global Positioning Satellite (GPS) location or merely a calling location area (e.g., geographical boundaries), included in the call setup message or from information obtained from location register  130 . The allowed geographic area for communication station  115  can be included in the call setup message or from information obtained from location register  130 . 
     Gateway  135  then determines whether it is able to determine the geographic location of communication station  120  (step  325 ). Gateway  135  can determine the location of communication station  120  by accessing inter-domain element  155 , gateway  150 , call processing element  140  or location register  145 . However, when gateway  135  is not be able to determine the geographic location of communication station  120  (“No” path out of decision step  325 ), the gateway includes the geographic location of and the allowed geographic area for communication station  115  in the call request message, and passes the message to the next network element towards communication station  120  (step  330 ). Steps  325  and  330  will be performed by the next network element towards communication station  120  until one of the network elements has the ability to determine the geographic location of the second communication station. 
     When gateway  135  is able to determine the geographic location of communication station  120  (“Yes” path out of decision step  325 ), then gateway  135  determines the geographic location of communication station  120  (step  335 ). When a network element other than gateway  135  has the ability to determine the location of communication station  120 , that network element will perform the acts of step  335 . Gateway  135  then determines whether communication station  120  is currently located in an allowed geographic area for communication station  115  (step  340 ). When communication station  120  is not located in an allowed geographic area for communication station  115  (“No” path out of decision step  340 ), then the call is denied (step  345 ). If, however, communication station  120  is located in an allowed geographic area for communication station  115  (“Yes” path out of decision step  340 ), then the call is allowed to proceed (step  350 ). 
     Which one of the particular network elements that performs the method of  FIG. 3  depends upon access to location information of the called communication station. Accordingly, whichever network element of gateways  135  and  150 , inter-domain element  155  or call processing element  140  has access to location information for communication station  120  can perform this method to enforce the calling restrictions. In some embodiments messages may need to be converted by gateway  135 , inter-domain element  155  and/or gateway  150 . In addition, a combination of different network elements can perform the method of  FIG. 3  to enforce the calling restrictions. Depending upon implementation, the call request can include the calling communication station&#39;s calling restrictions. The calling restrictions can include the current geographic location of and the allowed geographic areas for the calling communication station. 
     The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.