CN1171479C - Virtual numbering scheme for interoperability between heterogeneous networks - Google Patents

Abstract

The present invention provides a multi-protocol addressing scheme that allows for full interoperability between networks in a heterogeneous environment. According to exemplary embodiments, a system and method are provided for statically or dynamically assigning a virtual number parameter to a user requesting access. The virtual number parameter is a generic routing address that provides all possible routing addresses compatible with the routing technology supported by the system serving the specific user (eg IP, ATM, X.25, User@Domain, E.164, etc.). Through the use of this virtual number parameter, it is helpful to establish a call between heterogeneous networks.

Description

Virtual numbering scheme for interoperability between heterogeneous networks

background

The present invention relates generally to communication systems, and more particularly to techniques and structures for establishing connections in a cellular communication environment, which includes both telecommunications and data communication networks.

The Global System for Mobile Communications (GSM) describes a European standard for communications and the corresponding Public Land Mobile Network (PLMN), whose purpose is to provide consistency so that users can access any GSM system communication system anywhere without equipment compatibility issues least. In this way, the PLMN telecommunication system provides mobile users with the ability to travel freely within the GSM system and use the mobile services provided therein.

Figure 1 shows an exemplary conventional wireless GSM telecommunication network. A traditional wireless GSM telecommunication network generally includes a base transceiver station (BTS), a base station controller (BSC), a mobile switching center (MSC) with a visitor location register (VLR), and a home location with an authentication center (AuC). Register (HLR). Each BTS provides communications for one or more mobile stations (MS) located within various cells or areas of the wireless network. A BSC controls the operation of one or more BTSs. The BSC is interconnected with the MSC, and the MSC forwards the information to the intended destination (for example, the Public Switched Telephone Network PSTN). Each MSC is associated with a HLR and VLR. The HLR stores location information and subscriber data, which defines the services each mobile station is authorized to use. The VLR stores subscriber data for those mobile stations currently located within the service area of the corresponding MSC. Additional information on conventional wireless telecommunications networks can be found in US Patent No. 5,862,481 to Kulkarni et al. and US Patent No. 5,867,788 to Joensuu, both of which are expressly incorporated herein by reference.

In traditional telecommunication schemes, when a mobile station enters a new MSC coverage area or the mobile station is activated, the mobile station first attempts to register with the serving MSC. The mobile station completes the registration process by sending an associated identity, such as an International Mobile Subscriber Identity (IMSI) number, to the serving MSC. Those skilled in the art will understand that the IMSI is mapped by the system to the MSISDN of the mobile station. The serving MSC thereafter uses this information to communicate with the particular HLR storing the subscriber information of the requesting mobile station in order to inform the HLR of the mobile station's new location and to retrieve subscriber information from the HLR for the mobile station. The user information is downloaded to the VLR serving the MSC. The serving MSC then uses this user information to perform any requested authentication tests. Once the authentication test is satisfied, the MSC provides the mobile station with the services defined by the user data.

Figure 2 illustrates a conventional telecommunications scheme in an ANSI41 system for setting up a call between a first mobile station in the coverage area of an originating MSC and a second mobile station in the coverage area of a serving MSC. In step a, the originating MSC receives a call origination request from the first mobile station and the dialed mobile station address digits (ie, the directory number of the second mobile station). The originating MSC sends a location request (LOCREQ) message to the HLR storing the subscriber information of the second mobile station (step b). If the dialed mobile station address has been assigned to a legitimate user, the HLR sends a routing request (ROUTREQ) message (step c) to the VLR currently registered with the second mobile station. The VLR then forwards the routing request message to the serving MSC (step d). As a response to the route request message, the MSC requests service information (ie user data) of the second mobile station from the VLR (step e). If the second mobile station has not previously been registered with the VLR and thus is not known to the VLR, or the information requested by the MSC does not exist at the VLR, the VLR requests the information from the HLR (step f). In response, the HLR sends the requested information to the VLR (step g), which in turn routes the information to the serving MSC (step h). The serving MSC assigns a temporary local directory number (TLDN) to the second mobile station and returns this information to the VLR (step i), which then returns the information to the HLR (step j).

A TLDN is a temporary routing number used to route calls to a serving system. After receiving a setup message from the originating system the TLDN for the specific call is de-allocated and the TLDN used as the called party address in the originating system is mapped to the corresponding recipient identity (eg IMSI). The call establishment technique is limited to ISUP or registration signaling (such as SS7 or CAS) tightly coupled with the transport technique used.

When the HLR receives the TLDN, it returns a location request response message to the originating MSC (step k). Thereafter, using the existing interconnection protocol (such as SS7) and the routing information described in the location request response message, the originating MSC establishes a voice path to the serving MSC (step 1).

Although voice has been and will continue to be an important part of mobile communications, over the past decade it has become increasingly common for consumers to use mobile communications devices to transmit data rather than voice. The possibility of sending and receiving e-mails, gaining web access using a web browser is being hotly discussed as a service that will be used more and more in wireless communication systems. As such, future communication systems may contain a combination of telecommunications and data networks through which calls may be routed. As a result, modifications to existing telephone addressing techniques are necessary in order to provide a competitive advantage to telecom operators/service providers in the data communications industry using IP-based or other data communications-based addressing schemes.

A need exists for a system and method that modifies the addressing scheme of traditional telecommunications systems to facilitate call setup in environments that include combined telecommunications and data communications networks.

summary

The present invention seeks to overcome the above-mentioned shortcomings of the art by providing a multi-protocol addressing scheme which allows for full interoperability between networks in a heterogeneous environment. According to an exemplary embodiment of the present invention, a system and method are provided for statically or dynamically assigning a virtual number parameter to a user requesting access. The virtual number parameter is a generic routing address that provides all possible routable addresses (IP, ATM, X.25, user@domain, E.164) compatible with the routing technology supported by the system serving the particular user. Call establishment between heterogeneous and incompatible networks is facilitated through the use of virtual number parameters.

Brief description of the drawings

Through the following description of preferred embodiments in conjunction with the accompanying drawings, the above-mentioned purpose and features of the present invention will be more apparent, wherein:

Figure 1 illustrates a conventional wireless GSM telecommunication network;

Figure 2 illustrates a conventional telecommunication method for setting up a call between a first mobile station within the coverage area of an originating MSC and a second mobile station within the coverage area of a serving MSC;

Figure 3 shows an exemplary heterogeneous environment in which the addressing techniques of the present invention can be employed;

Figure 4 illustrates the use of the virtual number parameters of the present invention in an exemplary transaction to establish a connection between an originating system (such as an Internet service provider) and a mobile station roaming in a visited system (such as a PLMN), The originating system and the belonging system have different protocol capabilities;

Figure 5A illustrates the redirection method for establishing connections between networks with different protocol capabilities;

Figure 5B illustrates a proxy method for establishing a connection between networks with different protocol capabilities;

Figure 6 illustrates the use of the virtual number parameters of the present invention in a second exemplary transaction for a mobile in an originating system (such as an Internet Service Provider (ISP)) and roaming in a visited system (such as a PLMN) establish a connection between stations where the originating system and the home system have matching protocol capabilities; and

Figure 7 illustrates an exemplary call forwarding transaction using the VPN address of the present invention.

Detailed description of the invention

In the following description, for purposes of explanation and not limitation, specific details are employed, such as specific circuits, circuit components, techniques, etc., in order to provide a thorough understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods, devices, and circuits are omitted so as not to obscure the description of the present invention.

As previously stated, future communication systems will provide the ability to route information through systems comprising telecommunications networks (eg, SS7 networks) and data communication networks (eg, the Internet). The addressing mechanism currently used in telecommunication networks is closely integrated with the transmission technology adopted, such as SS7, which uses E.164, E.212, SS7 point generation or other types of addressing. As a result, current addressing schemes cannot handle the various transport-independent schemes that will exist in future communication systems (eg, systems that include both data communication and telecommunications networks). The present invention provides a system and method for establishing a connection in a heterogeneous environment, ie an environment comprising a telecommunications network and a data communication network. According to an exemplary embodiment of the present invention, a generic routing address (called Virtual Number Parameters (VNP)) is employed to handle the multi-protocol routing mechanism. The VPN provides the necessary routing mechanisms to allow the originating system to select a routing address from the VPN and a compatible call setup protocol from the capabilities of the serving system to set up and route the call. In those cases where VPN is not supported, the system will fall back to existing solutions (such as TLDN).

Figure 3 shows an exemplary heterogeneous environment in which the virtual number parameters of the present invention are employed. As shown in the figure, the exemplary heterogeneous environment includes an IP-based service network 300, an SS7-based origin network 310, and a home network 320, wherein the home network can be, for example, an IP-based network, an SS7-based network and so on. As one skilled in the art will understand, a mobile station's home network is the network that contains the HLR that stores subscriber data and location information for that particular mobile station. For simplicity, each network is assumed to be similarly organized (ie, each network contains multiple base transceiver stations and base station controllers, a mobile switching center, a visitor location register, a home location register, etc.). It will be further understood that in such a system there should be some sort of cooperation agreement between the operators of all heterogeneous networks. The serving system, home system and originating system may be part of any network using any agreed transmission/routing/control technology. Therefore, in such a heterogeneous environment, a call can be initiated from one data network to a telecommunications network, and vice versa, from a first data communication network to a second data communication network, or from a second data communication network. One telecommunication network originates to a second telecommunication network.

The VPN addressing techniques of the present invention are described with reference to an exemplary heterogeneous environment as shown in FIG. 3 . In FIG. 3, it is assumed that the mobile station MS has roamed out of its home coverage area (ie out of the area covered by the home system 320) and into the coverage area of a data communication network (such as IP-based network 300). When a mobile station roams into or becomes active within the coverage area of the serving network 300 (ie, an IP-based network), the mobile station registers with the serving network 300 by sending a registration request containing the mobile station's identity, eg IMSI.

According to an exemplary embodiment of the present invention, the service network 300 assigns a virtual number parameter (VNP) to the user in response to the registration request, and provides the parameter in the registration message to the home system 320 . According to the example where the service network 300 is an IP-based network, the VPN contains an IP address in addition to any other kind of address compatible with the routing technology supported by the service system. In other words, the VPN of the present invention is a specific user or an addressable network entity (such as a terminal, etc.) unique landmark identification name address. A VPN contains information such as address type, address length, and the address itself, and the VPN is added to existing network transactions, such as database queries, call delivery, roaming, redirection, and so on. The registration message also contains the IMSI of the mobile station and information indicating the protocol capabilities of the service network 300 (such as SIP, H.323, HTTP, etc.), and optionally contains a timer to set the effective time period of the VPN. It can be understood that without a timer, the VNP can be assigned as long as the mobile station is registered.

After receiving the registration message from the serving network 300, the home system 320 stores the VNP, acknowledges the registration message and starts a timer to monitor the VNP. The timer can be provided by the service system that owns the VPN as mentioned above, and can also be generated by the home system. The serving system may also request the home system to assign a VPN on its behalf. In case the home system generates a timer to monitor the VPN, the serving system is notified when the timer expires. The serving system can then request that VPN monitoring continue or request that the VPN for that particular user be discarded. In the deregistered and/or inactive state (ie timer expires), the home system clears the VPN from the user's database and terminates monitoring.

In another embodiment, the terminal used by the user may also have the ability to provide a routable address in the VPN attribute. In this state, the content of VPN attributes can be negotiated with the service system. If the serving system will not support any possible routable addresses, it can provide connectivity by tunneling requests and payloads from or to endpoints.

Figure 4 illustrates the use of the virtual number parameter of the present invention in an exemplary transaction in which a mobile connected at the originating system (such as an Internet service provider) and roaming at a visited system (such as a PLMN) Established between stations, where the originating system and the home system have different protocol capabilities. A user from the originating system (ie ISP in this example) attempts to locate a registered user currently roaming in a PLMN (ie serving/visited system). According to an embodiment of the present invention, since it is assumed that the home system cannot directly communicate with the originating data communication network, a PLMN gateway is used. The location request includes inter alia the address of the called party and the protocol capabilities of the originating system and is routed from the serving system to the PLMN gateway. The gateway system analyzes the request and the address of the called party, which may be an Internet type address. Gateways perform or require mapping of addresses to, for example, E.164 address types. The gateway system then analyzes the new address received from the mapping function (eg DNS) and forms a location request to the corresponding home system in order to obtain the VPN. The request contains additional call information (such as call type, bearer capability, etc.) and protocol capabilities of the originating network.

The home system analyzes the request and, with a valid VPN stored at the subscriber's home system HLR, the home system routes the VPN to the originating system after successfully matching the protocol capabilities of the serving system with those of the originating system.

If the VPN is not available for the subscriber in the HLR, the home system then initiates a request to the serving system connected to the subscriber. This request also contains the call information and capabilities received by the originating system. The service system locates the user, allocates a service channel if necessary, and reserves the requested data processing resources (eg, interworking function, service terminal, etc.).

In this regard, the serving system can select between different packet call routing options based on serving system capabilities and originating system capabilities. The following options are possible:

1) Return a VPN containing eg an IP address to the originating system. In the originating system, the PLMN gateway forwards the received address to the ISP network. The ISP network then establishes a new session to the address provided by the VPN.

2) Return an E.164 type routing number (eg a Temporary Local Directory Number (TLDN)) to the originating system. This routing number is then used by the PLMN gateway within the originating system to establish a connection with the serving system. This option can be selected in those cases where the system does not support VPN.

If the IP address previously assigned to the user has expired, a new IP address will be included in the routing request return result as a VPN. The home system stores this new routing IP address and includes it in the response to the location request returned to the origin system. If the protocol capabilities of the serving system do not match those of the originating system, the home system can select another gateway capable of handling the protocol mapping between the serving system and the originating system, so that there is a successful connection establishment result. The home system can choose to include the address of the gateway in the response to the originating system (redirect method), or the home system uses a proxy server to establish a connection to the serving system through the gateway (proxy method) and inform the originating system of the gateway's address and connection state information (such as connection method and result). The initiating system then establishes or completes a connection to the service system via the gateway from which the connection has previously been established to the service system. If any failure occurs in connecting the gateway to the service system (eg proxy failure, etc.), the originating system is notified with corresponding failure information.

Figures 5A and 5B illustrate the redirection and proxy method described above. In FIG. 5A, a user in the originating network, when attempting to locate a registered user, sends a location request to the home system, including inter alia the protocol capabilities of the originating system (step 501). In response, the home network sends a request (step 502) to the serving network, which locates the registered user and allocates the appropriate resources (note that in this example and the following example corresponding to Figure 5B, it is assumed that the home system does not contain User's active VPN). Together with the protocol capabilities of the serving network, the serving network sends a VPN to the home network (step 503). After determining that the serving network and the originating network have different protocol capabilities, the home network selects a gateway that can handle protocol mapping. The home network includes the address of the gateway in the message sent to the originating network (step 504). The originating network then sends a connection request to the gateway (step 505), and the gateway establishes a connection with the serving network (step 506). Thereafter, the user and registered users communicate via the gateway (steps 507a and 507b).

Figure 5B shows a proxy method for establishing connections between networks with different protocol capabilities. In step 551, the subscriber in the originating network sends a location request to the home network, including in particular the protocol capabilities of the originating network, when attempting to locate a registered subscriber. In response, the home network sends a request (step 552) to the serving network, which locates the registered user and allocates the appropriate resources. Together with the protocol capabilities of the serving network, the serving network sends a VPN to the home network (step 553). After determining that the serving network and the originating network have different protocol capabilities, the home network selects a gateway that can handle protocol mapping. The home network establishes a connection with the serving network via the gateway by using a proxy server (steps 554-556). In step 557, the home network then notifies the originating network of the address of the gateway and connection status information (such as connection method and result). The originating system then completes the connection with the gateway (steps 558 and 559).

Figure 6 shows the use of the virtual number parameter of the present invention in a second exemplary transaction, between an originating system (such as an Internet Service Provider (ISP)) and a mobile station roaming in a visited system (such as a PLMN) A connection is established where the originating and home systems have matching protocol capabilities. Since the originating system and the home system have matching protocol capabilities, the originating network in FIG. 6 does not include a PLMN gateway.

Similar to the exemplary transaction shown in Figure 4, a user of the Internet attempts to locate a registered user currently roaming in the PLMN. Since, as previously mentioned, the home system has the ability to communicate directly with the ISP or other data communication network, no gateway is required. In this way, the ISP sends a location request directly to the home system, which contains, inter alia, the address of the called party and the protocol capabilities of the originating system.

In case the HLR of the home system contains an active VPN for the user, the VPN is routed from the HLR to the originating system. When the HLR does not contain a valid VPN for the user, the home system initiates a request to the serving system to connect the user. The serving system pages the registered user, allocates a traffic channel if necessary and reserves the required data processing resources (eg, interworking functions).

If the IP address previously assigned to the registered user has expired, a new IP address is included in the routing request return result from the service network as the VPN. As mentioned above, the result returned by the routing request may also include a timer for monitoring the use of the VPN. The home system stores the new IP address and includes it in the response to the location request back to the originating system (ie, ISP). The Internet Protocol capabilities of the serving system are also included in the response to the initiating system. In those cases where the protocol capabilities of the originating system and the serving system match, the call is established directly from the ISP to the serving system, using the IP address provided by the serving system. If the protocol capabilities of the serving system differ from those of the originating system, the home system may choose to establish the call using redirection or proxy methods as described above.

Figure 7 shows an exemplary call forwarding transaction using the VPN of the present invention. Similar to the exemplary transaction described above with respect to FIG. 4, a call is established between an Internet service provider and a registered user in a PLMN. It is assumed here that, in response to the request from the home system, the service system returns a TLDN in E.164 format to the gateway. The originating system then establishes a connection using the TLDN provided by the serving system. If the registered user has not responded after a predetermined time-out period, the serving system sends a redirection message to the originating system indicating that the registered user has not responded. In those cases where the redirect message contains the redirect address (ie the VPN), the originating system uses that address to establish the connection. However, when the redirection message does not contain a redirection address, the originating system requests a redirection address from the home system. The home system sends the VPN to the originating system, which then establishes a connection to the address provided by the VPN.

As is evident from the above embodiments, modifications to existing telecommunication network entities and associated interfaces are required. It can be understood that traditional telecommunication protocols can be modified to support the above functions, or new protocols can be developed. The present invention provides the following enhancements to traditional telecommunication networks:

• Telecom databases and network entities capable of supporting multi-protocol addressing schemes (eg, IP, User@Domain, ATM, X.25).

• The ability to provide all available alias addresses (E.164, IP addresses, names, etc.) for user identification, authentication, translation and routing for a specific operation.

• The ability to identify the preferred addressing type to use for each operation when communicating with another network entity.

The address-handling capabilities of each node are known to the entire network using one or more of the following processes: broadcast methods, cooperative agreements manually managed in each network entity, or through operations at each exchange (such as transactions in ASNI41 The address processing capability is provided in the processing capability parameter, etc.).

• In SS7 networks, messages carrying digits for identification, routing, redirection, etc. will include other optional addresses in the VPN optional parameters.

• The lifetime of a VPN assigned to a registered user is the time monitored by the serving system and/or the home system.

• The home system stores the VPN and is able to locate users, route incoming calls, route and forward calls from any type of communication system.

• To terminate the access, the home system indicates the call type, eg different types of packet data calls (SIP, H.323, etc.).

• The ability to support a new type of global translation in SCCP, providing translation of virtual number addresses to destination addresses.

• A VPN considers locating a user and routing the call, regardless of the routing technology used by the network entities.

• The content of the VPN attribute is flexible and can be negotiated with the service system.

By using virtual number parameters, the present invention provides the ability to dynamically or statically assign all possible routing addresses to users requesting access to establish connections in an environment combining telecommunications and data communication networks. The VPN provides all possible routing mechanisms, allowing an originating system to select a routing address from the VPN and a compatible call setup protocol from the capabilities of the serving system in order to establish and route the call. The VPN can be assigned by the home system or the serving system during user registration, or by a gateway or other system during call routing. The VPN of the present invention can also be distributed by the user's own terminal.

The foregoing describes the principles, preferred embodiment and mode of operation of the invention. However, the invention should not be considered limited to the particular embodiments discussed above. For example, while many of the exemplary embodiments mentioned above illustrate the use of specific routing protocols, those skilled in the art will appreciate that the invention is not so limited. In fact, the invention is equally applicable to any routing protocol. Thus, the above-described embodiments should be considered as illustrative rather than restrictive, and it should be understood that those skilled in the art can make those embodiments without departing from the scope of the present invention as defined in the following claims. Revise.

Claims (41)

1. A method of providing interoperability in an environment comprising telecommunications and data networks, said method comprising the steps of: assign virtual number parameters; and establishing a connection between said telecommunications and data networks using said virtual number parameters, Wherein the virtual number parameter is a general routing address. 2. The method of claim 1, wherein said virtual number parameters include multi-protocol addressing information. 3. The method of claim 1, wherein said virtual number parameters are assigned during registration. 4. The method of claim 1, wherein said virtual number parameters are assigned during call routing. 5. The method of claim 1, wherein said virtual number parameters are assigned by a serving network. 6. The method of claim 1, wherein said virtual number parameters are assigned by a home network. 7. The method of claim 1, wherein said virtual number parameters are assigned by a gateway. 8. The method of claim 1, wherein said virtual number parameters are assigned by a user terminal. 9. The method of claim 1, wherein said assigning step comprises the step of: transmitting a location request by a first user in an originating system of one of said networks to a home system of a second user in another of said networks, said second user being located at within the coverage area of the service system; and A response including the assigned virtual number parameter is transmitted by the home system to the originating system. 10. The method of claim 9, wherein said virtual number parameter is a multi-protocol address assigned by said serving system. 11. The method of claim 9, wherein said virtual number parameter includes at least one address matching network capabilities of said serving system. 12. The method of claim 9, wherein said location request includes an indication of protocol capabilities of said initiating system. 13. The method of claim 12 further comprising the step of: In response to the location request, it is determined whether valid virtual number parameters for the second user are stored in the home network. 14. The method of claim 13 further comprising the step of: transmitting, by the home system to the serving system, a request for a routing address when a valid virtual number parameter is not present in the home network; transmitting virtual number parameters and an indication of protocol capabilities of the serving system to the home system in response to the request for the routing address; and determining whether the protocol capabilities of the initiating system and the serving system match, wherein said virtual number parameters are transmitted to said originating system when protocol capabilities match, and said originating system establishes said connection using the appropriate protocol and said virtual number parameters. 15. The method of claim 14 further comprising the step of: A redirection procedure is performed when the protocol capabilities do not match. 16. The method of claim 14 further comprising the step of: An agent program is executed when the protocol capabilities do not match. 17. The method of claim 13 further comprising the step of: When a valid virtual number parameter is determined to exist, determining whether the protocol capabilities of the originating system and the serving system match, wherein said virtual number parameters are transmitted to said originating system when protocol capabilities match, and said originating system establishes said connection using the appropriate protocol and said virtual number parameters. 18. The method of claim 17 further comprising the step of: A redirection procedure is performed when the protocol capabilities do not match. 19. The method of claim 17 further comprising the step of: An agent program is executed when the protocol capabilities do not match. 20. The method of claim 1, wherein the allocation of said virtual number parameters is monitored using a timer. 21. A system for providing interoperability in environments comprising telecommunications and data networks, the system comprising: means for assigning virtual number parameters; and means for establishing a connection between said telecommunications and data networks using said virtual number parameters, Wherein the virtual number parameter is a general routing address. 22. The system of claim 21, wherein said virtual number parameters include multi-protocol addressing information. 23. The system of claim 21, wherein said virtual number parameters are assigned during a registration process. 24. The system of claim 21, wherein said virtual number parameters are assigned during call routing. 25. The system of claim 21, wherein the means for distributing is a service network. 26. The system of claim 21, wherein the means for distributing is a home network. 27. The system of claim 21, wherein the means for distributing is a gateway. 28. The system of claim 21, wherein the means for distributing is a user terminal. 29. The system of claim 21 further comprising: means for transmitting, by a first user in an originating system of one of said networks, a location request to a home system of a second user, said home system being in another of said networks, said said second user is located within the coverage area of the service system; and means for transmitting, by said home system to said originating system, a response containing said assigned virtual number parameters. 30. The system of claim 29, wherein said virtual number parameter is a multi-protocol address assigned by said serving system. 31. The system of claim 29, wherein said virtual number parameter includes at least one address matching network capabilities of said serving system. 32. The system of claim 29, wherein said location request includes an indication of protocol capabilities of said initiating system. 33. The system of claim 32 further comprising: Means for determining whether valid virtual number parameters for the second subscriber are stored in the home network in response to the location request. 34. The system of claim 33 further comprising: means for transmitting, by said home system to said serving system, a request for a routing address when a valid virtual number parameter is not present in said home network; means for communicating virtual number parameters and an indication of the protocol capabilities of the serving system to the home system in response to the request for the routing address; and means for determining whether the protocol capabilities of the initiating system and the serving system match, wherein said virtual number parameters are communicated to said originating system when protocol capabilities match, and said originating system establishes said connection using the appropriate protocol and said virtual number parameters. 35. The system of claim 34, wherein said home system performs a redirection procedure when said protocol capabilities do not match. 36. The system of claim 34, wherein said home system executes an agent program when said protocol capabilities do not match. 37. The system of claim 33 further comprising the step of: means for determining whether protocol capabilities of said originating system and said serving system match when a valid virtual number parameter is determined to exist, wherein said virtual number parameters are communicated to said originating system when protocol capabilities match, and said originating system establishes said connection using the appropriate protocol and said virtual number parameters. 38. The system of claim 37, wherein said home system performs a redirection procedure when said protocol capabilities do not match. 39. The system of claim 37, wherein said home system executes an agent program when said protocol capabilities do not match. 40. The system of claim 29, wherein said means for transmitting a location request is a gateway. 41. The system of claim 21 further comprising a timer for monitoring said virtual number parameters.

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