WO2009006071A2

WO2009006071A2 - Method and apparatus for dynamic and spontaneous roaming agreement of heterogenous networks

Info

Publication number: WO2009006071A2
Application number: PCT/US2008/067877
Authority: WO
Inventors: Zhi Fu; Nitin Jian; Vishnu O Ram O.V.; John C. Strassner; Saumya G. Upadhyaya; Minho Shin
Original assignee: Motorola, Inc.
Priority date: 2007-07-02
Filing date: 2008-06-23
Publication date: 2009-01-08
Also published as: WO2009006071A4; WO2009006071A3; WO2009006071A9

Abstract

A system includes a foreign service provider (405) to provide wireless services within a foreign network. A foreign server (415) handles authentication, authorization, and accounting for the wireless services provided by the foreign service provider (405). A processing device (445) detects a mobile station (400) associated with a home service provider (410) requesting at least one wireless service. A communication element (455) establishes a communication channel between the foreign server (415) and a home server (425). A negotiation element (450) negotiates wireless coverage details for the mobile station (400) between the home service provider (410) and the foreign service provider (405) in response to a minimum level of trust being established between the foreign server (415) and the home server (425). Wireless services are provided by the foreign service provider to the mobile station in response to a successful negotiation.

Description

METHOD AND APPARATUS FOR DYNAMIC AND SPONTANEOUS ROAMING AGREEMENT OF HETEROGENOUS NETWORKS

Technical Field

[0001] This invention relates generally to implementing roaming agreements among wireless networks.

Background

[0002] Current wireless systems implement static and formal roaming agreements between providers. Such static roaming agreements are manually negotiated and implemented to allow roaming among networks when providing wireless services to a particular mobile station.

[0003] Heterogeneous networks are converging to provide Internet Protocol ("IP") services. In the telecommunications world of the future, there will be many different networks such as, for example, Global System for Mobile Communications ("GSM"), Universal Mobile Telecommunications System ("UMTS"), Code division multiple access ("CDMA"), Wireless Local Area Network ("WLAN"), Worldwide Interoperability for Microwave Access ("WiMax"), Digital subscriber line ("DSL"), Cable, vehicular networks, and mesh networks. Each of these networks may be owned by a different entity. To realize the seamless mobility vision and to provide users with the services they want regardless of their location, heterogeneous networks need to work together seamlessly and automatically.

[0004] A problem arises, however, as a result of the static contracts between the providers of these networks. Existing work on converged networks or converged services assumes pre-established formal roaming agreements between networks. Such formal roaming agreements constitute a serious limitation to network convergence and seamless mobility. First, there will be numerous providers with different sizes and locations, and it is practically impossible for one provider to have roaming agreements with all other providers. Second, it may not be worth the effort of establishing formal roaming agreements for short and spontaneous sessions. A customer, however, will be disconnected if he is under coverage of a local provider that does not have a formal roaming agreement with the home provider of which he is a subscriber. Current systems do not have the ability to establish roaming agreements on-the-fly . Moreover, the requirement of having pre-established formal roaming agreements between providers can be a costly and time-consuming process.

[0005] A broker-based system has been deployed. Within a broker-based system, a home service provider for a mobile subscriber and a foreign service provider each have a roaming agreement with a broker provider. In this system, all of the data traffic must pass through the broker service provider. This approach, however, adds a layer of cost due to the requirement of the use of the broker service provider as an intermediary. Moreover, the broker service provider can be a potential bottleneck in the event that it becomes heavily loaded or overloaded with data traffic.

Brief Description of the Drawings

[0006] The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages all in accordance with the present invention.

[0007] FIG. 1 illustrates a mobile station and various service providers according to at least one embodiment of the invention;

[0008] FIG. 2 illustrates a process for the mobile station to receive wireless service from the first foreign service provider according to at least one embodiment of the invention;

[0009] FIG. 3 illustrates communications between the mobile station, a first foreign service provider, and the home service provider according to at least one embodiment of the invention;

[0010] FIG. 4 illustrates a system for a mobile station to receive IP-based services from a foreign service provider according to at least one embodiment of the invention; [0011] FIG. 5 illustrates a latch-on process for the mobile station being provided access to Wireless Application Protocol ("WAP") services according to at least one embodiment of the invention; and

[0012] FIG. 6 illustrates a method for enabling spontaneous inter-working between a foreign service provider and a home service provider according to at least embodiment of the invention.

[0013] Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments of the present invention. Also, common and well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.

Detailed Description

[0014] Generally speaking, pursuant to these various embodiments, a method and system is provided for establishing roaming agreements on-the-fly between service providers. The teachings discussed herein are directed to a novel Authentication, Authorization, and Accounting ("AAA") architecture for enabling policy-based negotiation to establish dynamic partnerships between service providers on-the-fly.

[0015] When a user of a particular service provider desires to use a mobile station, such as a cell phone, in a country, such as Russia, other than their home country, currently used systems in the art would require the user's home service provider to have already established a formal roaming agreement between the user's home service provider and a service provider in Russia in order for the Russian service provider to service the user's mobile station. Pursuant to the teachings discussed herein, however, the user may use the mobile station in Russia and the user's home service provider will negotiate a dynamic roaming agreement on-the-fly with the Russian service provider, provided that a minimal level of trust can be established between the Russian service provider and the user's home service provider. [0016] In the event that the user, for example, has a mobile station that utilizes GSM and there is nearby GSM network when the user attempts to use the mobile station and connect to a network, the user's home service provider may attempt to negotiate a roaming agreement on-the-fly with the foreign service provider. Upon powering up the mobile station or otherwise attempting to connect to a GSM network, the user's mobile station may transmit a service request or other signal that is received by the foreign service provider. During the association and authentication process, the mobile station may transmit certain information, such as a user identification ("ID") and information about the mobile station's home service provider. Upon receipt of such information, the foreign service provider attempts to contact the mobile station's home service provider, for example, via an Internet connection or some other network connection to negotiate for the right for the foreign service provider to service the mobile station.

[0017] In order to enter into the negotiation, "basic trust" must be established between the foreign service provider and the home service provider. This trust may be established based on each service provider's membership in a designated consortium in which all signatories have agreed to a basic set of rules regarding liabilities and responsibilities, customer care, fault management, minimum security, billing procedure, and other functionalities. Alternatively, the trust may be established through a third party evaluation model where an independent trusted third party evaluates different providers, giving them a certificate with a relative score. A provider may check another provider's score on the fly through the third party to determine the trustworthiness of an unknown provider. According to a third trust model, a transitive trust model, participating providers build a set of established trusts between them, and additional trust relationships are derived through the use of transitive trust. After the basic trust has been established, the service providers further negotiate to reach an agreement on specifics of service, such as the quality of service ("QoS"), security, and charging to meet their requirements or policies.

[0018] Accordingly, by using the teaching discussed herein, a robust system and method is realized for dynamically negotiating roaming agreements on-the-fly without the need for pre-existing formal roaming agreements. [0019] FIG. 1 illustrates a mobile station 100 and various service providers according to at least one embodiment of the invention. The mobile station 100 has a home service provider 105 that utilizes GSM. The home service provider 105 provides GSM service within a home GSM network coverage 110. The mobile station 100 utilizes the GSM technology and receives wireless service from the home service provider 105 when located within the coverage area of the home GSM network coverage 110.

[0020] In the event that, for example, the mobile station 100 travels to a location outside of the coverage area of the home GSM network coverage 110, as shown in FIG. 1, the mobile station 100 will need to connect to a different network to receive service. In the event that the home service provider 105 has a pre-established roaming agreement in place with a foreign service provider providing coverage in the area in which the mobile station 100 is currently located, the foreign service provider may provide coverage in accordance with the pre-established roaming agreement. If, however, the foreign service provider does not have a pre-existing roaming agreement with the home service provider 105, a roaming agreement between the foreign service provider and the home service provider 105 may be dynamically established on-the- fly-

[0021] As shown in FIG. 1, the mobile station 100 is within the coverage area of a foreign GSM network coverage 115 being serviced by a first foreign service provider 120 that implements the GSM technology. The mobile station 100 is also within the coverage area of a foreign WiM ax network coverage 125 being service by a second foreign service provider 130 that implements the WiMax technology. In the event that the mobile station 100 is capable of utilizing GSM or WiMax, the mobile station 100 may receive wireless service from either the first foreign service provider 120 or the second foreign service provider 130. In this case, however, the mobile station 100 only implements the GSM technology. Accordingly, the mobile station 100 will attempt to receive wireless service from the first foreign service provider 120.

[0022] First, the mobile station 100 is powered up by a user, i.e., mobile subscriber, or otherwise attempts to connect to a GSM network. FIG. 2 illustrates a process for the mobile station 100 to receive wireless service from the first foreign service provider 120 according to at least one embodiment of the invention. First, at operation 200, the mobile station 100 transmits identification information to the first foreign service provider 120 that utilizes GSM. The mobile station 100 might not know of the existence of the first foreign service provider 120 and may broadcast a signal capable of being received by any GSM service providers within a certain range. Upon receipt of response from the foreign provider 120, the mobile station 100 starts an association and authentication process with the first foreign provider 120 and will send its identity information in the process. The identification information transmitted by the mobile station 100 includes the identity of the mobile subscriber, i.e., the user and/or the transceiver platform itself, using the mobile station 100 and the identity of the mobile subscriber's home service provider 105, as shown in FIG. 1.

[0023] Next, at operation 205, the first foreign service provider 120 sends a response to the mobile station 100. The response serves to indicate that the mobile station's 100 identification information was received or may request additional identification information. The first foreign service provider 120 includes a foreign AAA server that is in communication with the Internet or some other network, as discussed below with respect to FIGS. 3 and 4. The home service provider 105 for the mobile station 100 includes its own home AAA server. Both the foreign AAA server and the home AAA server are utilized in the authentication of the mobile subscriber of the mobile station 100 and the dynamic negotiation of a roaming agreement between the first foreign service provider 120 and the home service provider 105 such that the first foreign service provider 120 will agree to service the mobile station 100.

[0024] At operation 210, the first foreign service provider's AAA server contacts the home service provider's AAA server. This contact may be made through an Internet connection or some other network connection. When the mobile station 100 provides its identification information to the first foreign service provider 120, some of the relevant information included may be the domain name of the home service provider, and then a Domain Name Service ("DNS") lookup (through an SRV RR record) will reveal network address for the home service provider's AAA server. Trust is established between the home service provider's AAA server and the first foreign service provider's AAA server at operation 215. The establishment of trust is discussed below with respect to FIG. 3. Next, at operation 220, the first foreign service provider's AAA server and the home service provider's AAA server dynamically negotiate a roaming agreement to allow the first foreign service provider 120 to service the mobile station. The negotiation is discussed in further detail below with respect to FIG. 3. At operation 225, the regular authentication process starts for the home service provider and the foreign service provider to authenticate the mobile station and vice versa. Finally, at operation 230, the first foreign service provider 120 services the mobile station 100. The EAP may be utilized to authenticate the mobile station 100 during the various operations discussed above with respect to FIG. 2.

[0025] FIG. 3 illustrates communications between the mobile station 100, the first foreign service provider 120, and the home service provider 105 according to at least one embodiment of the invention. As shown, the mobile station 100 is in communication with an Access Controller ("AC") implementing EAP protocol or other protocols for authentication process of the foreign service provider 120. Upon detecting the presence of the mobile station 100, the Access Controller 200 transmits a message to the mobile station 100 requesting the identity of the mobile station 100 as well as the type of coverage and/or services desired by the mobile station 100. Upon receipt of this message, the mobile station 100 transmits the requested information back to the first foreign service provider 120. The response is received by a foreign AAA server 205 implementing a Partnership Management Application ("PMA"). The foreign AAA server 205 may also transmit a message containing an access request to the mobile station.

[0026] Upon receiving the identification and request information from the mobile station 100, the foreign AAA server 205 attempts to contact a home AAA server 210. This contact is made via an Internet connection or a connection across some other network. To connect to the home AAA server 210, the foreign AAA server 205 may access a known domain name or Internet address for the home service AAA server 210. This Internet address can be obtained with a DNS lookup with the domain name given by the mobile station 100. [0027] After accessing the home AAA server 210, a basic level of trust must initially be established between the foreign AAA server 205 and the home AAA server 210. If the basic level of trust is established, then a partnership negotiation for a roaming agreement is dynamically negotiated between the foreign AAA server 205 and the home AAA server 210. Finally, the first foreign service provider 120 provides service to the mobile station 100.

[0028] The basic level of trust may be established in several different ways. One way of establishing a basic level of trust is through membership in a known consortium. The parties to the consortium are service providers that each agree upon a basic set of rules regarding items such as security, billing, and other functionality. The providers may carry a consortium-issued certificate. Providers carrying this certificate are trusted by other consortium providers that their subscribers will pay for the services as set forth in the basic agreement/set of rules.

[0029] Another way of establishing trust is via a third-party evaluation model. According to this model, an independent trusted third-party evaluates different service providers and gives them a certificate with a relative score. A service provider may check another provider's score on the fly through the third party to determine the trustworthiness of an unknown provider.

[0030] An additional way of establishing trust is through a transitive trust model. In this model, participating providers build a set of established trusts between them. Use of transitive trust will derive additional trust relationships.

[0031] In each of the consortium model, the third-party evaluation model, and the transitive trust model, some sort of certificate and certificate verification will suffice to establish a basic trust level. With the basic trust as a starting point, the home service provider 105 and the first foreign service provider 120 will further negotiate to reach agreement on specifics regarding service, QoS, security, and charging to meet their requirements/policies.

[0032] In the event that the parties are signatories to a consortium, details of the master agreement are agreed to before the mobile station 100 attempts to received wireless service from the first foreign service provider 120. During the subsequent negotiation between the home AAA server 210 and the foreign AAA server 205, once it has been established that both the home service provider 105 and the foreign service provider 120 are signatories of or members of the consortium, they both agree on a basic level of agreement as specified in the master roaming agreement that does not need to be negotiated. Instead, they focus on negotiating the other details, such as specific Quality of Service ("QoS") parameters, security configurations and charging that are not determined in the Master roaming agreements. Members of the consortium may sign the paperwork for the master agreement or sign up through a secure online connection, or in any other suitable manner. The master agreement includes provisions for various items, such as settlement procedures, limitations on liability, and/or customer care responsibilities.

[0033] During the negotiation, the parties only focus on a few critical items. As a result of most of the roaming agreement items already having been decided by virtue of membership in the consortium, the subsequent dynamic negotiation between the parties can take place quickly, thereby minimizing the amount of time that a user of the mobile station would have to wait before receiving wireless service from the foreign service provider.

[0034] In an embodiment where the mobile subscriber's home service provider provides, for example, 3G Packets Switched ("PS") -based services, such services may be accessible in the event that the mobile station 100 connects to a foreign service provider that maintains a Wireless Local Area Network ("WLAN"). For example, if the home service provider 105 maintains a Wireless Application Protocol ("WAP") gateway for providing WAP and Multimedia Messaging Service ("MMS") services, these WAP and MMS services should also be accessible to mobile subscribers in a WLAN environment. Without accessing the 3GPP home network, the WLAN may merely provide an IP connection and the services tailored to the cellular mobile stations would not be made available. Accordingly, the user of the mobile station 100 would then be able to use IP-based services such as web browsing through the WLAN.

[0035] FIG. 4 illustrates a system for a mobile station to receive IP-based services from a foreign service provider according to at least one embodiment of the invention. As shown, a mobile station 400 is within range of a foreign service provider to provide coverage via a WLAN. The mobile subscriber/user of this mobile station normally utilizes a home service provider 410 that provides 3GPP -base service. In this case, however, the mobile station 400 is too far away from the home service provider 410 or is otherwise unable to connect to the home service provider 410 and therefore attempts to connect to the foreign service provider's WLAN. In order to connect to the WLAN, the mobile station needs to be a dual-mode 3GPP and WLAN capable of communicating with both 3GPP and WLAN networks. The mobile station 400 may be EAP-capable for authentication purposes.

[0036] As shown, the foreign service provider includes a foreign AAA server 415 and an EAP-AC (Access Controller) 420. Upon receiving a service request from the mobile station 400 and subsequently receiving the identity and services requested, the foreign AAA server 415 contacts a home AAA server 425 of the home service provider 410 via the Internet 430 or some other network and performs a negotiation, as discussed above with respect to FIGS. 2 and 3.

[0037] After a successful negotiation, the mobile station may utilize various IP- based services. A visited network 435 may be disposed between the home service provider 410 and the foreign service provider 405. The visited network 435 may utilize 3GPP. The visited network 435 may include a Wireless Access Gateway ("WAG") 440, and the home service provider 410 may include a Packet Data Gateway ("PDG") 445 to route the foreign service provider's 405 WLAN user data traffic.

[0038] The foreign service provider 405 and the home service provider 410 may each be parties to multiple consortiums and may share at least one membership in the same consortium, such as Consortium X. Consortium X may have a master roaming agreement that includes various items such as, for example, dispute settlement procedures, limitations of liability, billing procedures and responsibilities, customer care responsibilities, fraud tools and processes, agreement suspension and termination factors, minimum and/or maximum charges for airtime or wholesale rates, and a minimum security configuration. Members of Consortium X may have signed the master roaming agreement and agreed upon the responsibilities and liabilities, and Consortium X issued a certificate to its members.

[0039] The foreign service provider 405 may utilize a processing device 445 to detect the mobile station 400 requesting at least one wireless service. A communication element 455 may be included to establish a communication channel between the foreign AAA server 415 and the home AAA server 425. A negotiation element 450 negotiates wireless coverage details for the mobile station 400 between the home service provider 405 and the foreign service provider 410.

[0040] FIG. 5 illustrates a latch-on process for the mobile station 400 being provided access to Wireless Application Protocol ("WAP") services, such as web browsing tailed to cell phones, check voice mail, send emails, and perform texting, according to at least one embodiment of the invention. First, at operation 500, the mobile station 400 detects an unknown foreign service provider, such as that shown in FIG. 4. The foreign service provider 405 may provide service via a WLAN. At operation 505, the mobile station 400 is associated with the foreign service provider but is not yet authenticated. EAP is then begun. The foreign service provider's Access Point ("AP") sends an EAP -request/identity message to the mobile station at operation 510. Next, at operation 515, the AP receives the identity and/or other identification information from the mobile station 400 and forwards this information to the foreign AAA server 415. The foreign AAA server 415 finds the identification of the mobile station's 400 home service provider 410 and determines that there is no prior roaming agreement in place. At operation 520, the foreign AAA server 415 contacts the home AAA server 425 and they find a common consortium to which they both belong. The contact is made through some routing mechanism. The foreign AAA server 415 and the home AAA server 425 initially exchange identities of the consortiums to which they belong and then find the common one to which they both belong.

[0041] The foreign AAA server 415 and the home AAA server 425 use consortium certificates which had previously been issued to them by the consortium, to mutually authenticate and establish an IPSec between them at operation 525. Basic trust is established based on verifying and authenticating through the consortium certificate. At operation 530, the foreign AAA server 415 and the home AAA server 425 negotiate the roaming agreement details that were not specified in their master agreement with the common consortium. The foreign service provider 405 and the home service provider 410 may negotiate items in parallel such as (a) air rate charge for the foreign service provider tunneling user data traffic to the home service provider's network; (b) security configuration (e.g., authentication method, security configuration for tunneling); and (c) QoS requirement for characteristics such as the desired data rate. The home service provider 410 and the foreign service provider 405 need to agree on whether this negotiated rate and configurations should be applied to all other users within the same group as the current user (such as prepaid or postpaid, and gold service subscribers or silver service subscribers), and the agreement lifetime, and should also record their new partnership profile.

[0042] A determination is subsequently made regarding whether the negotiation was successful at operation 535. If "no," pan EAP-failure with an error code "negotiation failure" message is sent to the mobile station and processing returns to operation 500. If, on the other hand, the negotiation was successful, processing proceeds to operation 540 where an authentication method is determined, and an EAP-request/access challenge message is sent to the foreign AAA server 415. Through several round trips of EAP challenge response, if the authentication succeeds, at the last step when the EAP-success is sent the WAG or PDG address will be sent to the foreign AAA server 415.

[0043] At operation 545, the regular authentication process starts for the home service provider and the foreign service provider to authenticate the mobile station and vice versa. At operation 550, the mobile station 400 may begin using services, i.e., user traffic begins. The user data traffic is routed and tunneled from the foreign service provider's Access Gateway ("AG") to WAG to PDG to access data services on the home service provider's 3GPP network. Finally, at operation 555, accounting information is collected and sent to the home AAA server 425. The AP and the foreign service provider's AG collect the accounting info and send this information to the home AAA server 425. [0044] The method described above with respect to FIG. 5 has been described with respect to a foreign service provider 405 utilizing WLAN, and a home service provider 410 utilizing 3GPP. It should be appreciated, however, that a similar, or the same, provider could also be applied to the inter- workings of networks such as WiMax-3GPP, 3GPP-WiMax, WLAN- WiMax, WLAN-Cable, and so forth.

[0045] FIG. 6 illustrates a method for enabling spontaneous inter-working between a foreign service provider 405 and a home service provider 410 according to at least one embodiment of the invention. First, at operation 600, the foreign service provider 405 and the home service provider 410 establish a secure channel to protect their negotiation. They may use an IPSec process to negotiate specific security algorithms and establish a secure tunnel to protect their negotiation. IPSec enables certificate-based mutual authentication and establishment of a secure tunnel for protecting confidentiality, authenticity, and integrity of the traffic.

[0046] Next, at operation 605, business trust is established. During the negotiation, the first important thing to establish is trust between the foreign service provider 405 and the home service provider 410. Through mutual trust, the foreign service provider 405 ensures that it will be paid and the home service provider 410 ensures that the foreign service provider 405 is a legitimate and trusted partner.

[0047] Based on the trust models discussed above, the method for two providers to establish basic trust is to present and verify each other's respective certificate. One service provider may have multiple types of certificates and they may negotiate on which certificate is acceptable to the other. The messages to be exchanged are trusted Certificate Authority ("CA") identities. Furthermore, they will exchange other information, such as, for example, the size of customer base, to determine qualification of the potential partner.

[0048] Next, at operation 610, the foreign service provider 405 and the home service provider 410 agree on a session profile, including the service and QoS profile. The home service provider 410 intends to ensure that the basic QoS is satisfactory and the foreign service provider 405 intends to provide service to as many non-subscribers as possible without sacrificing the QoS for subscribers. Therefore, they negotiate to reach agreement on specific service profile and QoS profile. The messages to be exchanged may include information relating to items such as data rate and service type.

[0049] At operation 615, the foreign service provider 405 and the home service provider 410 agree on session security. The session security includes mechanisms for protecting user traffic. The messages to be exchanged may include authentication mechanisms such as, for example, EAP- Transport Layer Security ("TLS") or EAP- Authentication and Key Agreement ("AKA"). The messages may also include security algorithms and security mechanisms such as, for example, Advanced Encryption Standard ("AES") or Data Encryption Standard ("DES") for encryption.

[0050] Finally, at operation 620, the foreign service provider 405 and the home service provider 410 agree on a billing method and price, as well as any other billing- related issues. Each provider may have a specific policy regarding how much to charge users on particular services. The price will be based on user profiles/categories and the type of service offered. As in a formal agreement, the billing method, billing address, and specific price to charge needs to be agreed upon.

[0051] In most cases, after the negotiation tunnel and business trust are established, the last three negotiations can be done in parallel simultaneously to speed up the negotiation process. The negotiation may be done, for example, in simple propose/answer exchanges similar to those in Session Description Protocol ("SDP"), Hypertext Transfer Protocol ("HTTP"), or IPSec Internet Key Exchange ("IKE") security exchanges.

[0052] Before conducting the negotiation, each of the home service provider 410 and the foreign service provider 405 prepares and specifies a set of policies that they want to meet for working with unknown providers. The foreign service provider's 405 policy in providing service to non-subscribers may include factors such as a home service provider 410 trust policy such as, for example, certification and qualification of the home provider that the foreign provider considers trustworthy enough to work with. The foreign service provider's 405 policy may include additional factors such as a negotiation secure channel policy, a non-subscriber session security policy, a non- subscriber session profile policy, and a non-subscriber billing policy. [0053] The home service provider's 410 policy for handling its subscribers accessing foreign service providers may include factors such as (a) a foreign service provider trust and qualification policy; (b) a negotiation secure channel policy; (c) a subscriber session security policy; (d) a subscriber session profile policy; and (e) a subscriber accessing foreign domain billing policy.

[0054] The embodiments described herein provide a detailed AAA system and method including policy-based negotiation, system entities and protocol message exchanges for enabling spontaneous inter-working among heterogeneous networks. An AAA server for a foreign network contacts an AAA server for a home network when a mobile station of a mobile subscriber to the home network attempts to utilize services provided by the foreign network. The foreign AAA server and the home AAA server establish a basic level of trust between each other such as, for example, by virtue of their respective memberships in a common consortium. Upon establishing this basic level of trust, the foreign network and home network may quickly negotiate details of a roaming agreement on-the-fly . A robust system and method is realized for dynamically negotiating roaming agreements on-the-fly without the need for pre-existing formal roaming agreements.

[0055] Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described embodiments without departing from the spirit and scope of the invention, and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept.

Claims

We claim:

1. A method, comprising: detecting, by a foreign service provider, a mobile station requesting at least one wireless service; determining an identity of a home service provider for the mobile station; establishing a communication channel between a foreign server for the foreign service provider and a home server for the home service provider; establishing at least a minimum level of trust between the foreign server and the home server; negotiating wireless coverage details for the mobile station between the foreign service provider and the home service provider; conducting a regular authentication process; and providing wireless service to the mobile station, by the foreign service provider, in response to the successful negotiating and authenticating.

2. The method of claim 1, wherein the foreign server comprises a foreign Authentication, Authorization, and Accounting ("AAA") server, and the home server comprises a home AAA server.

3. The method of claim 1, wherein the establishing a communication channel comprises establishing a secure channel.

4. The method of claim 1 , wherein the negotiating wireless coverage details comprises negotiating at least one of service delivery parameters, a session security, and billing details.

5. The method of claim 4, wherein the service delivery parameters comprise a session profile and Quality of Service (QoS) parameters.

6. The method of claim 4, wherein the session security comprises at least one of an authentication method and a security configuration for tunneling.

7. The method of claim 1 , wherein the foreign service provider and the home service provider are members of a consortium of service providers having agreements of basic roaming contract details.

8. The method of claim 1 , wherein the at least a minimum level of trust is established based on membership of the foreign service provider and the home service provider in a common consortium.

9. The method of claim 8, wherein the common consortium issues each of the home service provider and the foreign service provider a certificate prior to the negotiating.

10. A system, comprising : a foreign service provider to provide wireless services within a foreign network; a home service provider to provide the wireless services within a home network to a mobile station of a mobile subscriber of the home service provider, wherein the mobile subscriber is associated with the home service provider; a foreign server, of the foreign service provider, to handle authentication, authorization, and accounting for the wireless services provided by the foreign service provider; a home server, of the home service provider, to handle authentication, authorization, and accounting for the wireless services provided by the home service provider; wherein, in response to detection, by the foreign service provider, of a mobile station requesting at least one wireless service, and at least a minimum level of trust being established between the foreign server and the home server: wireless coverage details for the mobile station are negotiated between the foreign service provider and the home service provider, and a regular authentication process starts and then wireless service is provided to the mobile station, by the foreign service provider, in response to the negotiating.