# Patent

## Title
Method for implementing a wireless local area network (WLAN) gateway system

## Abstract

The invention of present provides for a real-time authentication and billing gateway for WLAN traffic. Notably, the improved method for implementing a Wireless Local Area Network (WLAN) gateway system enables telecommunications network operators (and like entities) to rate and bill for services accessed by the wireless user. The logic of the invention supports and furthers the art in regards to advanced real-time rating/billing in addition to providing for a variety of replenishment mechanisms for casual users via pre-paid vouchers and credit cards.

## Background
PRIORITY CLAIM
This application is a continuation of U.S. patent application Ser. No. 10/603,099, filed Jun. 19, 2003, the contents of which are incorporated herein by reference.


CROSS-REFERENCE TO RELATED APPLICATIONS
Patent application Ser. No. 10/348,972 entitled “Method for implementing an Internet Protocol (IP) charging and rating middleware platform and gateway system”.
Patent application Ser. No. 10/307,335 entitled “Improved method for implementing an Open Charging (OC) middleware platform and gateway system”.
BACKGROUND ART
Wireless Local Area Network (WLAN) technology represents an ever-evolving area of the art which enables high-speed wireless access to the Internet or to a company Intranet: Given that the range of such WLAN Access Points is in the order of one hundred (100) meters, such service offerings have traditionally remained limited to discrete locales or ‘hot spots’ beyond the traditional workplace, as the ubiquitous coffee shop, rail stations, airports and so forth.
The prior art teachings in this area remain quite limited in light of the state of the art (and evolution beyond such). Consider, U.S. Patent Application 20020176579 by Deshpande et al., entitled Location-based services using wireless hotspot technology, which provides for a method of providing location-based services to a wireless device using a hotspot access point, comprising: establishing a connection between the wireless device and the hotspot access point; and providing information associated with the physical location of the hotspot access point to the wireless device. However, the application by Deshpande et al. restricts the billing mechanism to one of three modalities—‘business’, ‘public’ or ‘personal’. The invention disclosed herein does not require a given billable service to be characterized or limited to one of the three modalities as explicitly stipulated by Deshpande et al.'s application. Furthermore, Deshpande et al. does not teach or intimate a method whereby the relevant authentication, accounting and charging information is communicated to a centralized authentication or billing server (such as those hosted by macroscopic wireless carriers). In addition, the U.S. Patent Application 20020176579 by Deshpande et al. does not teach or suggest a method whereby the location information affects the billing mechanism associated with the provision of services or capabilities to a given end-user as the case may be.
Further prior art also remain limited in its teachings. Consider U.S. Patent Application 20030051041 by Kalavade et al., according to its title provides for a method and apparatus for integrating billing and authentication functions in local area and wide area wireless data networks. However, Kalavade et al. relies on a non-repudiation scheme whereby the subscriber is required to provide some form of personal data (e.g. their name, an address, a date of birth, and one or more digits of a social security number). The invention disclosed herein does not require the use of personal data for the purpose of non-repudiation. Indeed, while the application by Kalavade et al. indicates that integration with a given ‘backoffice’ server (an HLR) is required, the application does not teach or suggest a method whereby the authentication sequences can be mapped into an appropriate sequence supported by contemporary networks which utilize the EAP, ANSI-41, GSM MAP, RADIUS, or DIAMETER protocols as the case may be. Furthermore, the patent application does not teach or suggest a method whereby alternative methods of payment can by supported (e.g. prepaid vouchers or credit cards).
And still further, International Application 03/032618 filed under the Patent Cooperation Treaty by Mellstrand et al., entitled Integration of Billing between Cellular and WLAN Networks, provides a method for integrating a cellular and wlan network for the purpose of billing via a ‘Sign-up Server’. However the application by Mellstrand et al., relies on the use of the GGSN in order to communicate with the HLR for the retrieval of user information and to authenticate the user. The invention disclosed herein does not require the use of the GGSN, nor is the disclosed invention restricted to GSM/GPRS based macroscopic networks. Furthermore, Mellstrand et al.'s application does not teach or suggest a method whereby wlan charges can be accrued against prepaid accounts nor does it intimate a method whereby alternative methods of payment (e.g. prepaid vouchers or credit cards) can by supported for the purpose billing WLAN access and usage.
REFERENCES CITED















U.S. Patent
March, 2003
Kalavade et al.
709/229


Application 20030051041


U.S. Patent
November, 2002
Deshpande
380/270


Application 20020176579

et al.









Foreign Patent Document(s)


    03/032618 April, 2003 PCT.


Other References


    GSM 03.40, Digital cellular telecommunications system (Phase 2+); Technical realization of the Short Message Service (SMS)
    GSM 09.02, Mobile Application Part (MAP) specification
    3GPP2 N.S0023, Network Support for MDN-Based Message Centers
    TIA TR 45.2, IS-841, TIAIEIA-41-D Based Network Enhancements for MDN Based Message Centers
    GSM 03.90, Digital cellular telecommunications system (Phase 2+); Unstructured Supplementary Service Data (USSD)—Stage 2
    TIA TR 45.2, IS-841, TIAIEIA-41-D Based Network Enhancements for MDN Based Message Centers
    TIAIEIA ANSI-41 Cellular Radiotelecommunications Intersystem Operations
    Diameter Base Protocol—draft-ietf-aaa-diameter-17
    RFC 2865 Remote Authentication Dial In User Service
    RFC 2866 RADIUS Accounting


TECHNICAL FIELD
The present invention relates generally to wireless telecommunications network implementations and gateway services, and, in particular, to an improved method for implementing a Wireless Local Area Network (WLAN) gateway system.
SUMMARY OF THE INVENTION
The invention of present provides for a real-time authentication and billing gateway system for Wireless Local Area Network (WLAN) traffic. The improved method for implementing a Wireless Local Area Network (WLAN) gateway system intermediates and connects WLAN users to the wireless network in question by easily and openly integrating into existing telecommunications networks thereby capitalizing on the existing value and art found in billing, messaging, and IN platforms of present.
The improved method for implementing a Wireless Local Area Network (WLAN) gateway system disclosed herewith provides real time authentication, billing and rating for Wireless Local Area Network (WLAN) traffic and/or other such broadband data services. The invention exists as part of a computer program product which resides within the telecommunication carrier's core network. By interfacing with multiple Access Controller's (ACs) over a Remote Access Dial In User Server (RADIUS), DIAMETER, or LDAP interface, WLAN users can gain network access from telecommunications network carrier controlled hot spots and partnered hot spot providers. By acting as a gateway between wireless LAN hot spots and the telecommunications carrier's IN infrastructure the improved method for implementing a Wireless Local Area Network (WLAN) gateway system has been articulated with the necessary logic and art to facilitate the billing of existing wireless prepaid and postpaid accounts. In further landmark embodiments, wireless users, within the appropriate coverage area, who do not have GSM accounts are able to utilize the improved method for implementing a Wireless Local Area Network (WLAN) gateway system as articulated and employed within a telecommunications carrier's network, through the creation of temporary accounts via credit card, voucher or similar means.
In additional embodiments the improved method for implementing a Wireless Local Area Network (WLAN) gateway system supports a variety of account replenishment mechanisms for wireless users via pre-paid vouchers, credit-cards and other such means.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a typical, non-limiting embodiment of the system level architecture employed in the disclosure of present.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1, although the invention of present exists as part of a computer program product, for the purposes of simplicity and ease of instruction, the improved method for implementing a Wireless Local Area Network (WLAN) gateway system 100 can be functionally divided between an AAA gateway 110 and a Session Controller 120 together with Charging 150 and Rating elements 140.
Continuing with reference to FIG. 1, in the preferred embodiment, the improved method for implementing a Wireless Local Area Network (WLAN) gateway system 100 behaves as an AAA server to the Access Controller (not shown) via mediation of AAA requests typically executed through the defacto standard RADIUS protocol. Practitioners and other honourable members skilled in the art will recognize that a variety of protocols (for example, DIAMETER and LDAP) and like logical instructions may be employed without diluting the intent and scope of the invention of present, and its inclusion herewith serves merely for the purpose of elucidation, simplicity and ease of instruction.
Still with reference to FIG. 1, the improved method for implementing a Wireless Local Area Network (WLAN) gateway system connects to the SMSC 40 using the Short Message Peer-to-Peer (SMPP) protocol and interface. (The SMPP interface 40A is required for WLAN non-repudiation for subscribers). Following subscriber authentication an SMS message is delivered to the subscribers MSISDN over SMPP and through the SMSC 40. If a reply message is received from the subscriber, WLAN service will be offered to the subscriber. If no reply is received within a configurable interval, then WLAN service is not provided to the subscriber. Practitioners and other honourable members skilled in the art will recognize that a variety of protocols and like logical instructions may be employed apart from SMPP without diluting the intent and scope of the invention of present, and its inclusion herewith serves merely for the purpose of elucidation, simplicity and ease of instruction.
Where relevant, access to the computer program product which implements the improved method for implementing a Wireless Local Area Network (WLAN) gateway system 100 can be accessed through an Unstructured Supplementary Service Data (USSD) Gateway 50A and related USSD access technologies (which remains well defined in the art including GSM 09.02 and GSM 03.90). In light of the state of the art, USSD is utilized as an optional interface instead of SMPP for non-repudiation purposes.
Those skilled in the art will recognize that SMS or USSD messaging mechanisms may also be used as a mechanism to modify subscriber preferences. The invention will also permit subscribers and network operators to make configuration changes via a (web-based) provisioning interface.
The authentication mechanisms referred to utilize SMS non-repudiation and blacklist functionalities, which are meshed to provide the said authenticating mechanism for typical subscriber access in a provision less mode. The dual mechanisms ensure a secure system to all fraud potentialities (aside from the regrettable theft of the mobile unit itself). Although in anticipating such eventualities, mobile unit theft could be handled via real-time barring using the blacklist functionality. Nonetheless, SMS non-repudiation ensured that the intended subscriber was, in fact, the subscriber outlined with the handset contract. Blacklist functionality provides for the barring of service for criteria such as other carrier subscribers, theft, fraud, and so on.
The improved method for implementing a Wireless Local Area Network (WLAN) gateway system, which mechanically exists as part of a computer program product, supports a variety of state of the art billing constructs which are reliant on the type of access mechanism utilized by the wireless user. The charging engine 150 provides superior flexibility and allows the telecommunications carrier to offer a variety of billing mechanisms to their wireless user base.
In further elucidating the art pertaining to WLAN billing, the logic of the improved method for implementing a Wireless Local Area Network (WLAN) gateway system 100 has been refined and articulated to support a number of scenarios/constructs; including, but not limited to, contract subscribers, voucher management system, credit card services and prepaid subscribers. The listed scenarios/constructs shall be outlined further, to facilitate ease of instruction, although practitioners skilled in the subject matter will recognize that the billing scenarios remain only bounded by the state of the art.
For contract subscribers, after said subscribers have authenticated with the computer program product which implements the improved method for implementing a Wireless. Local Area Network (WLAN) gateway system 100, the former invention tracks charges based on the subscriber rate plan (predefined). Said billing details are laid out in a telecommunications carrier-defined or otherwise flexibly defined Charging Detail Record (CDR). The CDR is then sent out/collected by downstream billing mechanisms 61 in a format compatible with the requisite art of said billing technologies.
For voucher access, the wireless user in question enters their voucher as user id and thereafter, a temporary password. Through an optional interface 63A (in a varying embodiment), the improved method for implementing a Wireless Local Area Network (WLAN) gateway system 100 validates the voucher through a voucher management system 63 (which remains well defined in the existing state of the art) and creates a WLAN session with said duration dependant upon the voucher amount and the given rate plan. The WLAN Session Controller 120 stores the available balance and periodically decrements as such. In advancing the art and in promoting its use thereof, voucher sessions support mobility. That is to say, a wireless user may enter a hotel and purchase a voucher for two (2) hours worth of use and subsequently only use one (1) therewith and log off. Said wireless user could then venture to a WLAN active airport, log back in with the voucher id and temporary password they chose and utilize the remaining hour. In alternate embodiments, the vouchers can be articulated as to expire within a certain time frame if not used to their exhaustion.
Now, where a credit card is used as the means of payment 62 (62A represents the interface), the logic internal to the improved method for implementing a Wireless Local Area Network (WLAN) gateway system 100 initially validates the credit card purchase of a set amount of time, and returns a correlation id to the user. In deference to the need to maintain credit card privacy and security, the invention does not store any credit card parameters locally. Credit card users retain comparable benefits and advantages as that of the former voucher user. (Said credit card user can log back in using the returned correlation id and temporary password they selected for their initial access).
Prepaid subscribers are billed via SCP account decrementing 64 (64A represents the interface) (which remains well defined in the art). Prior to authenticating, the logic and computer program product which implements the invention disclosed ensures that a sufficient balance exists and continues decrementing the SCP account 64 (said periodicity and amount of the account decrement is dependent on the used rate plan and billing interval settings) until the subscriber disconnects or the balance expires. In the latter scenario, the invention kills the session. To facilitate real-time SCP account debiting, the functionality associated with the improved method for implementing an Open Charging (OC) middleware platform and gateway system as detailed in patent application Ser. No. 10/307,335 is required to perform the necessary Prepaid charging functionality. Technicians skilled in the art will recognize that the invention of present need not be limited to the aforementioned Open Charging (OC) middleware platform and gateway system and other similar network implementations may be employed without diluting the intent and scope as such.
The improved method for implementing a Wireless Local Area Network (WLAN) gateway system may also be co-articulated and implemented with the method for implementing an Internet Protocol (IP) charging and rating middleware platform and gateway system as detailed in patent application Ser. No. 10/348,972, to enhance the packet/data rating and classification mechanisms inherent in the invention disclosed hereto. Technicians skilled in the art will recognize that the invention of present need not be limited to the aforementioned method for implementing an Internet Protocol (IP) charging and rating middleware platform and gateway system and other similar network implementations may be employed without diluting the intent and scope as such.
Optional manifestations of the invention may authenticate the subscriber using the authentication sequences prescribed in ANSI-41, GSM TS 09.02, ETSI TS 100974, and 3GPP TS 29.002 Mobile Application Part (MAP) specifications as amended from time to time. Those skilled in the art will recognize that International Mobile Subscriber Identity (IMSI) and alternative Mobile Station identifiers as well as subscriber Authentication parametric attributes retrieved from the Access Controller (not shown) may be used to initiate an authentication sequence with the HLR 70 and/or Authentication Center (not shown). Yet an alternative manifestation may leverage an alternative messaging sequence (for example, Send_Routing_Info_for_SM or SMS_Request for GSM and ANSI-41 based networks respectively) to confirm whether a given subscriber has an active subscription with a given network operator. Those skilled in the art will recognize that the messaging sequence messages may be used to correlate the location of the subscriber as inferred in the response message with the location of the subscriber as provided in the RADIUS based messages which emanate from the Access Controller (not shown).

## Claims

1. A method for authenticating and charging a user of a wireless local area network (WLAN) gateway system including a service management platform, an access gateway, a rating element maintaining profile information associated with a mobile computing device, a charging element maintaining charging details associated with the mobile computing device, and an interface for connecting the mobile computing device to the access gateway, the method comprising:
receiving, at the access gateway, authentication information for the user associated with the mobile computing device;
sending a first message from the access gateway to the mobile computing device;
if no reply to the first message is received from the user, then denying the mobile computing device access to said WLAN;
if a reply to the first message is received, then permitting the mobile computing device to access said WLAN; and
during the access to said WLAN:
sending an instruction from the access gateway to the rating element to determine a rate for packets carried between the mobile computing device and the WLAN to establish a rate of charge for the packets; and

sending an instruction from the access gateway to the charging element representing charging details associated with the access of said WLAN by the mobile computing device, the charging details based at least in part on the rate of charge.

2. The method of claim 1, wherein said access gateway emulates an authentication, authorization and accounting (AAA) server.

3. The method of claim 1, wherein sending the first message from the access gateway to the mobile computing device comprises sending the first message via a Short Message Peer-to-Peer (SMPP) interface to a Short Message Service Center (SMSC) for delivery to the mobile computing device, and wherein the reply message is received at the access gateway from the mobile computing device via the SMPP interface.

4. The method of claim 3, further comprising: receiving one or more additional messages from the mobile computing device at the access gateway via the SMPP interface; the additional messages including instructions to modify user preferences associated with the access of the WLAN via the access gateway.

5. The method of claim 1, wherein sending the first message from the access gateway to the mobile computing device comprises sending the first message via an Unstructured Supplementary Service Data (USSD) gateway connected to the access gateway, for delivery to the mobile computing device, and wherein the reply message is received at the access gateway from the mobile computing device via the USSD gateway.

6. The method of claim 5, further comprising: receiving one or more additional messages from the mobile computing device at the access gateway via the USSD gateway; the additional messages including instructions to modify subscriber preferences associated with the access of the WLAN via the access gateway.

7. The method of claim 1,
wherein said rate of charge is based on a classification assigned to each of said packets.

8. The method of claim 1, further comprising storing an available voucher balance, wherein the charging details include decrementing the available voucher balance.

9. The method of claim 8, further comprising: prior to permitting the mobile computing device to access the WLAN, sending a voucher validation instruction from the charging element via a voucher interface.

10. The method of claim 1, further comprising generating a correlation identifier and a temporary password prior to permitting the mobile computing device to access the WLAN, wherein the charging details include decrementing a credit card balance.

11. The method of claim 1, wherein the charging of the user occurs via a billing system of an existing telecommunications network.