Abstract:
A telecommunications system and method for increasing communications bandwidth for an Internet Service Provider (“ISP”) to accommodate temporary fluctuations in demand. The present invention utilizes an Advanced Intelligent Network (“AIN”) to re-direct calls from a subscriber to an ISP from the ISP&#39;s modem pools to a shared modem pool operated by a telephone service provider (“telco”) when the ISP needs additional bandwidth. The shared modem pool is controlled by an access server and a remote authentication dial-in user service server managed by the telco. The telco servers identify the identified ISP to receive the call by looking at the original number dialed by the caller. The telco servers then communicate with the proper ISP which determines whether or not the caller is a valid subscriber of the ISP.

Description:
BACKGROUND  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates generally to telecommunications systems. More particularly, the present invention relates to an advanced intelligent network system for providing flexible bandwidth to an Internet Service Provider commensurate with the demands for dial-up access to the Internet Service Provider&#39;s resources.  
           [0003]    2. Background of the Invention  
           [0004]    Over the last ten years, use of the Internet has grown rapidly. A large segment of this growth stems from an increase in individual dial-up subscribers. These dial-up subscribers use the public switched telephone network (“PSTN”) to establish connections to their Internet Service Providers (“ISPs”). FIG. 1 is a schematic diagram illustrating how these dial-up subscribers, or users, connect to their ISPs using PSTN  10 . To support multiple connections, ISPs must maintain numerous telephone lines connected to modems. Rather than advertising a different telephone number for each telephone line, ISPs generally advertise a limited number of telephone access numbers. Each telephone access number corresponds to one or more telephone lines. These telephone lines may be made up of, e.g., individual POTS lines, one or more T1 lines, or Primary Rate Integrated Services Digital Network (“PRI”) lines. For simplicity, the figures and discussion herein show the connections to be made up of PRI lines.  
           [0005]    As shown in FIG. 1, ISP  20  may provide multiple telephone access numbers, each corresponding to PRI lines connected to multi-line hunt groups (“MLHGs”). MLHGs are modem pools allowing multiple simultaneous connections to the ISP via a single telephone access number. A multi-line hunt group takes incoming subscriber calls and routes them to the first open modem in the modem pool. FIG. 1 shows four sets of PRI lines  26 - 29  connected to four MLHGs  22   a - 22   d , respectively. The MLHGs are controlled by access server  23 . When caller  30  dials one of ISP  20 &#39;s telephone access numbers (using computer  31 , modem  32  and subscriber line  33 ), PSTN  10  processes the call like any other call. That is, the call is routed between caller  30  and the called party (in this case, ISP  20 ) through one or more service switching points (“SSPs” or “switches”). If the lines corresponding to the dialed telephone access number are all busy, or “off-hook”, i.e., there are no voice  15  communications paths available, the caller gets a busy signal, which is provided by PSTN  10 .  
           [0006]    If lines are available, the ISP&#39;s switch, SSP  12  in FIG. 1, terminates the call. Access server  23  answers the call and determines whether or not the caller is a valid ISP subscriber. If the caller is valid, then access server  23  must determine which services the caller should have access to. Access server  23  queries caller  30  for information such as a username and password for use in validating caller  30  and determining caller  30 &#39;s authorized services. The dialog between caller  30  and access server  23  is usually performed automatically between access server  23  and communications software operating on computer  31 .  
           [0007]    Generally, ISPs use centralized servers to store and manage their subscriber databases. Remote Authentication Dial-In User Service (“RADIUS”) server  24 , having database  24   a , is functionally connected to access server  23  and provides this centralized management. Thus, access server  23  collects username and password information from caller  30  and passes it on to RADIUS server  24 . After RADIUS server  24  verifies caller  30 &#39;s username and password, it provides access server  23  with configuration information specific to caller  30 . Access server  23  uses the configuration information to provide the authorized services to caller  30 . Access servers and RADIUS servers are described in more detail in commonly assigned U.S. patent application Ser. No. 09/133,299, which is incorporated herein by reference in its entirety. Additional information on access servers and RADIUS servers may be found in Rigney et al.,  Remote Authentication Dial - In User Service  ( RADIUS ), Network Working Group, January, 1997, or in Rigney et al.,  RADIUS Accounting,  Network Working Group, April, 1997.  
           [0008]    An ISP incurs great costs for purchasing and maintaining the telecommunications infrastructure needed to operate its business. The ISP must pay its local telephone service provider (“telco”) for each telephone line maintained. Additionally, the ISP must purchase and maintain MLHGs and the associated modems for the groups. Finally, the ISP must manage and balance the load on each of its MLHGs in order to provide efficient connections for its subscribers. Due to the high cost of purchasing and maintaining the infrastructure, it is desirable for an ISP to provide only as many lines and modems as are required to accommodate its subscribers&#39; demand.  
           [0009]    It is well known in the art that not all subscribers connect to their ISPs at the same time. Additionally, not all subscribers connect every day, nor do they connect for the same length of time each session. For this reason, it is not cost-effective for ISPs to provide a 1:1 ratio of lines to subscribers. Instead, ISPs have developed formulas to determine the appropriate number of telephone lines required. In general, a telephone line to user ratio of at least 1:10 provides an acceptable level of service. However, as Internet usage continues to grow, it is becoming more difficult to predict the requirements for telephone lines into an ISP. Thus, a need exists for a system and method to balance the competing interests of reducing ISP costs and providing acceptable levels of service for ISP subscribers. A further need exists for a system and method providing ISPs with flexible access to increased telephone lines and modems, i.e., increased bandwidth, as the need arises to support the ISPs&#39; customers. A system and method is needed to provide such flexible bandwidth on demand for ISP&#39;s without significantly increasing the complexity or costs for ISP operations.  
         SUMMARY OF THE INVENTION  
         [0010]    The present invention provides a system and method allowing ISPs to dynamically expand the number of telephone lines and modems available to ISP subscribers dialing into ISP systems. The present invention utilizes an Advanced Intelligent Network (“AIN”) to provide an automated system and method for providing this flexible bandwidth to ISPs. AIN systems are described in U.S. Pat. No. 5,701,301, U.S. Pat. No. 5,774,533 and Bellcore Specification TR-NWT-001284, Switching Systems Generic Requirements for AIN 0.1, which are incorporated herein by reference in their entirety. FIG. 2 shows the important components of the AIN used in the present invention. The steps described herein can be performed by computer-readable program code operating on the various AIN components and other computer systems, as described below.  
           [0011]    In a preferred embodiment of the present invention, an AIN automatic flexible route (“AFR”) trigger is provisioned on the trunk group in SSP  212  providing PRI lines  226  into ISP  220 . The PRI lines are connected to MLHG  222  at the ISP, which is reached by dialing the corresponding telephone access number. The trigger is activated when a subscriber dials the telephone access number and there are no open lines available. In response to the trigger, a database query goes from SSP  212  to service control point (“SCP”)  215  via ss 7  network  213 . SCP  215  writes the contents of the called party number (“CdPN”) field, i.e., the dialed ISP telephone access number, into the calling party number (“CgPN”) field and specifies a new location to forward the call with instructions to monitor the call for termination status. The call is thus forwarded to the telco&#39;s shared modem pool, MLHG  219 , without losing the ISP telephone access number dialed by the subscriber. In this manner, the telco&#39;s proxy RADIUS server  217  can determine which ISP the call will be directed to.  
           [0012]    Acting on the instructions from SCP  215 , SSP  212  forwards the call setup message to SSP  214  since that SSP serves the telco&#39;s shared modem pool, MLHG  219 . SSP  214  terminates the call to MLHG  219 , provided a line is available. If the call is terminated, SSP  212  informs the SCP as requested by the termination notification message. Upon receipt of the informational message, the SCP updates a database used to track the number of users from the ISP using the telco&#39;s shared modem pool.  
           [0013]    Access server  218  records the CgPN and answers the call. Proxy RADIUS server  217  looks up the ISP domain based on the CgPN and routes the information to the ISP&#39;s RADIUS server  224 . RADIUS server  224  then initiates the point-to-point protocol session with the subscriber to validate the username and password.  
           [0014]    When the caller&#39;s session ends, i.e., when the call is disconnected, SSP  212  sends the SCP another informational message in response to the previous termination notification request. Again, the SCP uses the information to update its database to track the number of callers from each ISP using the telco&#39;s shared modem pool. This information provides the telco with any data necessary to manage the service. For example, the telco may charge ISPs for each session connected through the shared modem pool. In another example, the ISP may “subscribe” to a service allowing a pre-defined number of overflow customers. Once the slots for that ISP are in use, subsequent callers will receive a busy signal. The telco can create reports for analyzing usage trends for each ISP. For example, if one ISP is historically using a large portion of the shared modem pool, the telco may use the information in a marketing strategy to sell increased permanent bandwidth to the ISP.  
           [0015]    It is an object of the present invention to provide an automated system for increasing an ISP&#39;s capacity for dial-up subscribers.  
           [0016]    It is another object of the present invention to provide ISPs increased bandwidth on demand according to the ISPs&#39; requirements.  
           [0017]    It is another object of the present invention to use an Advanced Intelligent Network to provide efficient allocation of telecommunications resources among multiple ISPs.  
           [0018]    It is another object of the present invention to provide a system to increase Internet subscribers&#39; chances of obtaining a connection to their ISPs.  
           [0019]    It is another object of the present invention to provide increased bandwidth to an ISP in a manner transparent to the ISP&#39;s subscribers.  
           [0020]    These and other objects of the present invention are described in greater detail in the detailed description of the invention, the appended drawings and the attached claims. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 is a schematic diagram illustrating the systems and methods used to accommodate dial-up subscribers in the prior art.  
         [0022]    [0022]FIG. 2 is a schematic diagram showing the main components of an AIN used in an embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0023]    [0023]FIG. 2 shows the key components of the AIN used in the present invention. Such AIN components include one or more switches, SSP  211 ,  212  and  214 , SCP  215 , and Common Channel Signaling System 7 (“SS7”) network  213 . SSP  211  serves caller  230  who is connected via subscriber line  233 . Caller  230  uses computer  231  and modem  232  to dial into ISP  220  for connection to Internet  240 . ISP  220  has MLHG  222 , connected to SSP  212  via PRI lines  226 . MLHG  222  is controlled by access server  223 , which uses RADIUS server  224  for central management of ISP  220 &#39;s subscriber accounts. RADIUS server  224  has database  224   a  as shown in FIG. 2.  
         [0024]    In a preferred embodiment of the present invention, an Automatic Flexible Route (“AFR”) trigger is provisioned on SSP  212  for the trunk group supporting PRI lines  226 . As noted above, when caller  230  dials the telephone access number for ISP  220 , the AFR trigger will be activated only if all lines in the trunk group are busy. If a line is available, SSP  212  terminates the call to MLHG  222 , and ISP  220  processes the call directly. However, if all of the lines in the trunk group are busy, the AFR trigger prompts SSP  212  to issue a database query to SCP  215 . The database query is a standard AIN query and contains information such as a CgPN field and a CdPN field.  
         [0025]    SCP  215  responds to the query by checking database  215   a  for routing directions and updates a counter tracking the number of calls that have been rerouted for  220 . If the counter indicates that ISP  220  has no more slots reserved in shared modem pool  219 , SCP  215  instructs SSP  212  to issue a busy signal. In a preferred embodiment, SCP  215  updates another counter tracking the number of rejected callers and sends periodic reports to ISP  220 &#39;s RADIUS server  224  via a gateway server (not shown in FIG. 2). ISP  220  can use the information to determine if more hardware is necessary either within its own network, or if more slots should be purchased from the telco. Additionally, in a preferred embodiment, RADIUS server  224  can dynamically increase or decrease the number of reserved slots by sending authorization to SCP  215  via the gateway server.  
         [0026]    After determining that ISP  220  has an available slot, SCP  215  continues processing its response to SSP  212 &#39;s database query by replacing the CgPN with the CdPN and replacing the CdPN with a telephone access number for the telco&#39;s shared modem pool. For example, if the ISP&#39;s telephone access number is “222-222-1000,” the telco&#39;s shared modem pool, MLHG  219 , has telephone access number “222-333-1000,” and caller  230 &#39;s telephone directory number is “222-444-1000.” The database query from SSP  212  would contain the following information: CgPN=“2224441000” and CdPN=“2222221000.” In contrast, the response from SCP  215  would contain the following information: CgPN=“2222221000” and CdPN=“2223331000.” 
         [0027]    SCP  215  completes its response to SSP  212  by instructing SSP  212  to forward the call to the new CdPN and to monitor the call status. In a preferred embodiment, SCP  215  sends a Forward_Call instruction and a Send_Notification instruction. In response to the Forward_Call instruction and the new CdPN, SSP  212  forwards the call setup message to SSP  214  for processing. In response to the Send_Notification, SSP  212  will inform SCP  215  of whether or not the call is terminated, and if terminated, whether or not the call is answered. In addition, SSP  212  will inform SCP  215  when the call has ended, i.e., when the connection is dropped for an reason. This information is used by SCP  215  to update the counters discussed above.  
         [0028]    Once the call is connected to MLHG  219 , the telco&#39;s shared resources, i.e., MLHG  219 , access server  218  and proxy RADIUS server  217  process the call in lieu of processing by ISP  220 . Access server  218  answers the call and informs Proxy RADIUS server  217  of the CgPN and the port on which the call was connected. Proxy RADIUS server  217  looks up the CgPN in database  217   a  to determine which ISP the call should be routed to. Based on the CgPN, SCP  215  determines that the call is for ISP  220  so a message is sent to RADIUS server  224 . The message informs RADIUS server  224  of the subscriber&#39;s port and instructs RADIUS server  224  to initiate the point-to-point protocol session with the subscriber to validate the username and password.  
         [0029]    RADIUS server  224  communicates with access server  218  via router  216 . Access server  218  prompts caller  230  for the usual information, such as username and password. Access server  218  thus operates in place of access server  223 . Caller  230  is unaware of the changed routing for the call and is unaware that the access server processing the call is not one managed by the ISP. Access server  218  sends the username, password and CgPN to RADIUS server  224  for authentication.  
         [0030]    As shown in FIG. 2, router  216  functionally separates the various network connections to multiple ISPs. FIG. 2 shows ISPs  220 ,  250 ,  260 ,  270  and  280  connected to router  216  via interconnects  221 ,  241 ,  251 ,  261 ,  271  and  281 , respectively. In a preferred embodiment, these interconnects comprise frame relay s circuits forming “private” high-speed connections between the ISPs and the telco. Because proxy RADIUS server  217  supports multiple ISPs, each call coming into MLHG  219  must identify the caller&#39;s ISP. Proxy RADIUS server  217  has a database (not shown) listing the telephone access numbers for each ISP it serves. Using this database and the CgPN received from access server  218 , proxy RADIUS server  217  is able to identify the proper ISP.  
         [0031]    Proxy RADIUS server  217  forwards the username and password information on to the ISP&#39;s RADIUS server for verification. For example, since the CgPN is “2222221000,” proxy RADIUS server  217  looks in the database and determines that caller  230  is trying to access ISP  220 . Thus, proxy RADIUS server  217  sends caller  230 &#39;s username and password on to RADIUS server  224 . RADIUS server  224  verifies the information and informs proxy RADIUS server  217  of the result. If the username and password are valid, proxy RADIUS server  217  instructs access server  218  to grant access to the caller, using configuration information provided by RADIUS server  224 . If the username and password are invalid, proxy RADIUS server  217  instructs access server  218  to deny access to the caller.  
         [0032]    As noted above, SCP  215  keeps track of the number of subscribers from each ISP using the telco&#39;s shared resources for access. This information may be used in a variety of ways. For example, the telco may generate bills to the ISPs for “renting” the telco&#39;s resources. Such bills could be generated to charge the ISP according the minutes used by its subscribers during the billing period. Alternatively, the bills could be generated based on the number times the shared modem pool was accessed by an ISP subscriber. The telco may also use the information in sales and marketing strategies in dealing with its ISP customers. The data may help ISPs identify usage trends and could be used to project future requirements for subscriber support.  
         [0033]    The foregoing disclosure of embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many variations and modifications of the embodiments described herein will be obvious to one of ordinary skill in the art in light of the above disclosure. The scope of the invention is to be defined only by the claims appended hereto, and by their equivalents.