SYSTEM AND METHOD OF INTERNET ACCESS AND LOAD MANAGEMENT
The present invention relates generally to telecommunications, and more specifically, to a system and method of Internet access and management.
Background of the Invention
The use of computers and computer software in all of their various forms is widespread and is growing everyday. As well, powerful communication networks such as the Internet, have developed which allow computer software programs and data files to be easily accessed, exchanged, copied and distributed. The Internet is now a common medium for operating online auctions, academic and public forums, distributing publications such as newspapers and magazines, and performing electronic commerce and electronic mail transactions.
The demand for Internet services has grown far faster than the implementation of new and dedicated Internet infrastructure all the way to user's homes and businesses, so it has been common to rely on the existing Public Switched Telephone Network (PSTN) to provide the "last mile" of communication. The PSTN is the international telephone system which enjoys almost pervasive access in industrialized countries. The PSTN provides reliable and predictable quality that is suitable for "dial-up" Internet access.
Dial-up access refers to connecting a computing device such as a personal computer (PC), laptop computer or personal digital assistant (PDA) to a computing network via a modem and the PSTN. Dial-up access is much like a voice telephone connection, except that the parties at the two ends are computer devices rather than people. Information is transmitted over PSTN lines in analogue form, while computers manipulate data in digital form. Hence, a modem (modulator/ demodulator), is required to convert the computer's digital data to and from the analogue form that the PSTN carries.
Figure 1 presents an exemplary layout of a dial-up Internet communication system 30. The Internet 32 itself is represented by a number of routers 34 interconnected by an Internet backbone 36 network designed for high-speed transport of large amounts of data. User's computers 38 may access the Internet in a number of manners including modulating and demodulating data over a telephone line 40 using analogue audio frequencies, which requires a modem 42 and
connection to the Public Switched Telephone Network (PSTN) 44. The PSTN 44 in turn, connects to the Internet 32 via Network Access Servers (NAS) 46.
Web sites are maintained on servers 48 also connected to the Internet 32, which provide content and software applications to the User's computers 38. As Internet Service Provider (ISP) 50 may have one or many servers 48 under its supervision. Communications between user's computers 38 and the rest of the network 30 are standardized by means of defined communication protocols.
Internet Service Providers (ISPs) 50 or Internet Access Providers (lAPs), are companies that provide access to the Internet. For a monthly fee, ISPs 50 generally provide end users with the necessary software, username, password and access to the Internet and other services. ISPs 50 are considered by some to be distinguished from lAPs in that they also provide content and services to their subscribers, but in the context of this disclosure the distinction is not significant. Equipped with a telephone line 40 and modem 42, one can dial the telephone number of an ISP or ASP, to log on to the Internet 32 and browse the World Wide Web, and send and receive e-mail.
Figure 1 is something of a simplification, as ISPs 50 are often connected to the Internet 32 through Network Access Points (NAPs), rather than directly as shown in Figure 1. As well, the Internet itself is far more complex than that shown in Figure 1, as the Internet consists of a vast interconnection of computers, servers, routers, computer networks and public telecommunication networks. However, these details would be well known to one skilled in the art.
Although dial-up access to the Internet over PSTN lines is very common, this architecture does have significant limitations, including the following: 1. while an ISP 50 may have several NASs 46, each NAS 46 may be connected to the PSTN 44 via several trunks (PRI or T1/E1 ) and each one of the trunks (or set of trunks) might have a unique DN associated with it. This is regardless of the fact whether they are in the same location or spread across the nation. Therefore, users may have to dial several telephone numbers before they find a NAS 46 that has the capacity available for them to log on;
2. it does not allow ISPs 50 to balance the loading across their NASs 46 (also referred to as Points of Presence or PoPs);
3. it does not allow ISPs 50 to route calls around failed PoPs 46; and
4. it does not allow ISPs 50 to overflow calls from one PoP 46 to another.
Of course, until the user has access to the Internet 32, the Internet 32 cannot assist in establishing the telephone line 40 connection. Therefore, one must look to the PSTN 44 to provide the assistance. The PSTN 44 does have additional intelligence that may be employed to assist with Internet access in limited ways. The intelligent layer that exists for the PSTN 44 is called the IN (Intelligent
Network). An Intelligent Network (IN) is a telephone network architecture in which the service logic for a call is located separately from the switching facilities, allowing services to be added or changed without having to redesign switching equipment. IN is described as a "service-specific" architecture, that is, a certain portion of a dialled phone number, such as 800 or 900, triggers a request for a specific service. An IN may also be implemented as a "service-independent" architecture in which a given part of a telephone number can interpreted differently by different services depending on factors such as time of day, caller identity, and type of call. These architectures are generally referred as an Advanced Intelligent Network (AIN) in North America, and an Intelligent Network (IN) in Europe.
The IN is typically used to route voice calls across the PSTN 44 network, an example being toll-free access using 1 - 800 - xxx - xxxx numbers in North America. An exemplary layout of a PSTN/IN network 58 is present in Figure 2. When a call is placed on a telephone 60 using a toll-free number, the Central Office 62 to which the telephone 60 is connected, identifies the call as requiring IN processing. This determination is made by the nature of the dialed number. The CO 62 then directs the call through the Signal Transfer Point (STP) network 64 to access a central database called the Service Control Point (SCP) 66, to be processed. The SCP 66 decides where to route the call based on some static criteria such as the closest customer support center from where the call is being placed. In the case of a 1 - 800 - xxx - xxxx number, the SCP 66 will index its database with the dialled number and find a "regular" telephone number which corresponds to the 1 - 800 number. These "regular" telephone numbers are referred to as North American Numbering Plan (NANP) numbers in the art. This regular number is returned to the CO 62, and the call is routed accordingly.
However, the IN and AIN systems 58 are static; all the call routing logic has to be programed into the SCP 66 ahead of time, before it can make a decision as to where to route a call. Therefore, the existing IN infrastructure 58 cannot be used to route dial-up calls for Internet access because the SCP 66 does not have knowledge
of dynamic status of the related components in the IP (Internet Protocol) network needed to make a proper routing decision.
There is therefore a need for a system and method of Internet access and management.
Summary of the invention
It is therefore an object of the invention to provide a novel system and method of Internet access and management which obviates or mitigates at least one of the disadvantages of the prior art. One aspect of the invention is broadly defined as a method of managing public switched telephone network (PSTN) dial-up Internet access comprising the steps of: responding to the receipt of a request for dial-up access to an Internet
Service Provider (ISP) via said PSTN by: analysing Network Application Server
(NAS) operating data from said ISP. Another aspect of the invention is defined as an apparatus operable to execute the method steps of: responding to the receipt of a request for dial-up access to an Internet Service Provider (ISP) via said PSTN by: analysing Network
Application Server (NAS) operating data from said any one of claims 1 through 13. An additional aspect of the invention is defined as a system for executing the method the steps of: responding to the receipt of a request for dial-up access to an
Internet Service Provider (ISP) via said PSTN by: analysing Network Application
Server (NAS) operating data from said ISP.
An additional aspect of the invention is defined as a carrier signal incorporating software code executable to perform the method steps of: responding to the receipt of a request for dial-up access to an Internet Service Provider (ISP) via said PSTN by: analysing Network Application Server (NAS) operating data from said
ISP.
A further aspect of the invention is defined as a computer readable memory medium for storing software code executable to perform the method steps of: responding to the receipt of a request for dial-up access to an Internet Service
Provider (ISP) via said PSTN by: analysing Network Application Server (NAS) operating data from said ISP.
Brief Description of the Drawings
These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings in which: Figure 1 presents a physical layout of an exemplary Internet network 30 as known in the prior art;
Figure 2 presents a physical layout of an exemplary PSTN Intelligent Network 58 as known in the prior art; Figure 3 presents a flow chart of a method of Internet access and management in a broad embodiment of the invention; Figure 4 presents a physical layout of a system of Internet access and management in a preferred embodiment of the invention; and Figure 5 presents a block diagram of an apparatus for performing Internet access and management in a preferred embodiment of the invention; and Figures 6a, 6b and 6c present a flow chart of a method of Internet access and management in a preferred embodiment of the invention.
Detailed Description of Preferred Embodiments of the Invention
A method which addresses the objects outlined above, is presented as a flow chart in Figure 3. This figure presents a flow chart of a method of managing public switched telephone network (PSTN) dial-up Internet access. This method may be effected by responding to the receipt of a request for access to an Internet Service Provider (ISP) 50 from a central office (CO) 62 at step 70, by analysing Network Application Server (NAS) 46 operating data from the ISP 50 at step 72.
As described in the Background to the Invention, the PSTN 44 provides a convenient means of accessing the Internet 32 via a modem 42, using dial-up access, but the lack of management of this access results in several significant problems. The existing PSTN 44 can be modified to identify calls to an ISP 50 in the same manner as the existing IN or AIN calls are identified. If an incoming call is not identified as an ISP call at step 70, regular processing may be performed at step 74, or some other action may be taken, such as querying the caller, or dropping the
PSTN connection. This identification may be made at the end office or central office (CO) 62 of the PSTN 44, or at any other suitable point.
In response, the ISP call will initiate an analysis of the NAS 46 operating data from the ISP 50. These data may include, for example: Network Access Server
(NAS) 46 load, its proximity to the caller, and subscriber profile data such as QoS (Quality of Service). As well, the analysis performed on these data may be a matter of some simple binary tests, such as stepping through a list of available NASs 46 and detecting whether the NAS 46 has capacity, or be far more complex, as in the case of balancing or predicting loading of NASs 46, or re-distributing connections in the event of an NAS 46 failure.
The invention provides a number of advantages over the functionality available in the art. As noted above, the current SCPs 66 employed by the PSTN 44 are static databases which do not have the ability to communicate intelligently with the components of the IP network 32, such as routers and servers. Hence, the SCPs 66 are not able to make proper routing decisions for the Internet dial-up calls based on the policies governed by the IP network 32 elements and the values of real time parameters. The policies include subscriber policies, network status policies and many others that are only available on the IP network 32. In general, the invention allows the existing PSTN-based IN infrastructure to work with the IP-based network infrastructure to enable dial-up call routing based on the policies such as network and subscriber status, on a dynamic basis for every call.
With the IN infrastructure having visibility into the IP network 32 in this manner, the ISP 50 is able to offer the advantages of: 1. single telephone number access to an ISP 50, either locally or across the nation, with a single telephone number for multiple NASs 46 or PoPs;
2. load balancing of Internet traffic across their NASs 46 or PoPs;
3. routing of calls around failed NASs 46, PoPs, NAS ports or PRIs (a PRI is an ISDN service called a primary rate interface. It is described in greater detail hereinafter); and
4. transferring overflow calls to other PoPs 46.
To the PSTN local exchange carrier who buys and implements the system of the invention, it allows them to: 1. enter the Internet market; 2. generate additional revenues by providing enhanced IP access services to the ISPs 50 and Corporations; 3. reduce the congestion in their PSTN (Public Switched Telephone Network) 44 by intelligently and efficiently routing Internet dial-up calls to the ISP 50 and
Corporate PoP (Point of Presence) locations; and
4. allows the ISPs 50 to continue to own their Network Access Servers 46 and be able to buy IN (Intelligent Network) enabled IP access services from the carrier which they would not be able to use otherwise since they are not licensed as carriers. The end user benefits from the improved functionality and efficiency that his
ISP 50 enjoys, as well as improved ease of access to their ISP 50. The end user no longer has to dial multiple numbers to obtain access; a single telephone number is sufficient. Other advantages would be clear to one skilled in the art from the description of the invention herein. The preferred embodiment of the invention is presented with respect to the layout of Figure 4. This system 80 includes components described in the Background of the Invention: the Internet 32, user's computer 38, telephone line 40, modem 42, Network Access Servers (NASs) 46, Internet Service Provider (ISP) 50, Central Office (CO) 62 and Signal Transfer Point (STP) network 64. In the ISP domain of the this layout, the ISP 50 is shown to comprise both a
Network Management Server (NMS) 82 and an Authentication, Authorization and Accounting Server (AAA) 84.
Generally, an AAA 84 server receives the user's requests over the Internet 32 and an NMS server 82 administers the ISP's resources to supply the requested services. An AAA server 84 provides the NASs 46 with information that is used to authenticate hosts or users (authentication), to assign network privileges (authorization), and to record user network activity (accounting).
Authentication is the process of confirming that a person or device is who they claim to be. For example, to authenticate a remote host or person, a local host requests a username and password (from the other host or person) and then verifies that the username and password are valid by comparing them to values stored on an AAA server 84.
Authorization is the process of negotiating network access privileges and assigning the privileges to an interface. When assigned to an interface, these privileges apply to any person or device using the interface to gain access to the network.
Accounting is the basic back-end bookkeeping services required for cost allocation and statistical analysis.
In the Access Provider's Domain, the invention adds the Multispan Service Point™ (MSP) 86, and the optional Intelligent Peripheral 88. The MSP 86 is the active database and intelligent processor which interfaces with both the IN of the PSTN 44, and the ISP servers 82, 84. The structure of the MSP 86 is described with respect to Figure 5, and the functionality with respect to the flow charts of Figures 6a, 6b and 6c.
The optional Intelligent Peripheral 88 is used to collect additional dialed digits and pass them to the MSP 86. In the preferred embodiment described hereinafter, the Intelligent Peripheral 88 collects a personal identification number (PIN#) for authentication of the caller.
The general structure of the MSP 86 is presented as a block diagram in Figure 5. At the hub of this apparatus lies a central processing unit 90, which may consist of one or more microprocessors, micro-controllers, ASICs (application specific integrated circuits) and/or digital signal processors, or similar devices as known in the art, as well as any necessary supporting logic. The central processing unit 90 communicates with the PSTN 44 via an SS7 interface 92, and communicates with the Internet 32 via a TCP/IP interface 94. SS7 or CCS7 is the protocol used by the telephone systems worldwide to set up calls and provide transaction services; the TCP/IP (Transmission Control Protocol/Internet Protocol) is the suite of communications protocols used to connect hosts on the Internet. Both SS7 and TCP/IP are well known in their respective arts.
The invention is not limited to such protocols, as any required interface may be substituted. As well, the invention is not limited by the format of communication between the interfaces 90, 92 and the central processing unit 90. A storage medium 96 is also provided to store programming information as well as temporarily caching ISP performance data. This storage medium may be implemented in many ways, including any one of the following, or combinations of: RAM (random access memory), PROM (programmable read only memory) and its variations such as EPROM, EEPROM and Flash ROM, magnetic storage media such as hard disk drives, floppy disk drives and magnetic tape drives, optical storage media such as compact disk drives, or similar storage media as known in the art.
A terminal or personal computer (PC) 96 is also provided to serve as an interface for the system administrator, which may be used to monitor and program the MSP 86. This terminal 96 may be directly connected to the central processing
unit 90 as shown, or may be interconnected with a LAN (local area network), or remote connection, in a manner known in the art.
The preferred method of the invention is presented as a flow chart in Figures 6a, 6b and 6c. These flow charts describe the steps of call set up and tear down and the interaction between various components on the network for an Internet dial-up call.
At step 100, the subscriber uses his computing device 38 and modem 42 to dial a PSTN directory number (DN) to access an ISP 50. This operation is described in greater detail herein above. The ingress central office 62 or end-office, receives this call at step 102 and identifies an IN (Intelligent network) PODP (Public Office Dial Plan) trigger against the dialed DN, which causes processing to proceed to step 104. Such PODP triggers are standard to IN and AIN systems, and may consist of a single 7-digit number, a range of numbers, or a longer string of digits. If the call does not contain such a trigger, then regular PSTN call processing is performed at step 106.
At step 104, the ingress end-office 62 then builds and sends an IN routing query message to the MSP 86 for resolution. The IN protocol would depend on what protocol is supported by the local PSTN 44, and could be, for example:
1. TCAP (Transaction Capabilities Application Part), which is the application part of signalling system #7 (SS7). As noted above, SS7 is the protocol used by
North American telephone systems to set up calls and provide transaction services.
2. INAP (Intelligent Network Application Protocol) which specifies the information flows to be exchanged between the different entities of the IN functional model in terms of protocol data units (PDUs) described by ASN.1 (Abstract
Syntax Notation #1). The PDUs themselves represent Remote Operations in the scope of the Transaction Capability Application Part (TCAP); or
3. any other suitable variant of IN protocol.
For the central office switch 62, the MSP 86 is seen as another SCP 66. Therefore, when configuring the PODP trigger against a number in the CO 62 one has to tell it which SCP 66 it needs to send the routing query to; which is normal configuration practice. The destination SCP address is determined by a parameter called "point code". Point codes are used as addresses to identify network elements
in the SS7 network similar to that of IP addresses that are used to identify hosts in the IP network.
The MSP 86 receives the IN query at step 108 and decodes it to extract the called number and other fields. Based on this information, the MSP 86 indexes its database 96 to find the ISP profile to validate other parameters like port quota. At step 110, the MSP 86 then sends a RADIUS (Remote Authentication Dial-in User Service) authentication proxy query message to the ISP 50 asking it to validate the user based on the calling number.
RADIUS is a protocol to authenticate users who dial in to private networks. Typically, dial-in network access servers challenge callers for user name and password, which are checked against a RADIUS server. Optionally, the switch can collect PIN# (Personal Identification Number) from the user (using the Intelligent Peripheral 88) and send the PIN# as username authentication parameter to the ISP's Authentication, Authorization, and Accounting (AAA) server 82. The AAA server 82 of the ISP 50 then authenticates the caller at step 112 of
Figure 6b, based on either the calling number or the PIN#, and sends a RADIUS "authentication accept" response back to the MSP 86. As noted above, the AAA server 82 provides authentication, authorization and accounting services.
While step 114 shows the transmission of performance information such as the ISP's 50 NAS 46 resources, port/PRI status and NAS 46 status being sent to the Access Provider's MSP 86 by the ISP's 50 Network Management System (NMS) 84 as a finite step, it is preferably done on a continuous and real-time basis. This transmission is done using one or more of the protocols:
1. SNMP (Simple Network Management Protocol), which is a widely-used network monitoring and control protocol. Data is passed from SNMP agents, which are hardware and/or software processes reporting activity in each network device (hub, router, bridge, etc.) to the workstation console used to oversee the network. The agents return information contained in a MIB (Management Information Base), which is a data structure that defines what is obtainable from the device and what can be controlled (turned off, on, etc.).
2. DIAMETER, which is an AAA protocol like RADIUS, though DIAMETER has several other advantages over RADIUS which may result in the growth of its use in the industry. RADIUS was designed to function only with Serial Line Internet Protocol and PPP for standard analog modems, while DIAMETER
can be used for access authentication of handheld or other wireless computing devices, cellular phones or Ethernet-based virtual private networks (VPN). As well, DIAMETER allows remote servers to send unsolicited messages to clients, and has longer address spaces. 3. MGCP (Media Gateway Control Protocol), which is an IETF protocol for IP telephony. Working in conjunction with the Gateway Location Protocol (GLP), it enables a caller with a PSTN phone number to locate the destination device and establish a session. It provides the gateway-to-gateway interface for the Session Initialization Protocol (SIP), a less-complex alternative to the H.323 protocol, which is an ITU standard for transporting voice, video and data over packet-switched networks such as local area networks (LANs) and the Internet.
Having received the "authorization accept" message, the MSP 86 selects a routing number at step 116, based on the service logic parameters such as: 1. least cost routing;
2. traffic congestion on a route;
3. ISP's 50 NAS (Network Access Server) 46 and port availability corresponding to the routing number; or
4. NAS 46 type. Other parameters may also be considered, which would be clear to one skilled in the art.
The MSP 86 generates an active interim accounting record for the call setup at step 118. It also keeps track of number of calls per NAS 46 and per PRI basis to efficiently load-balance the traffic across the PoPs (Points of Presence) in a wide area network.
Primary Rate Interface (PRI) is an ISDN service designed for larger organizations. PRI includes 23 B-channels (30 in Europe) that can carry voice or data at rate of 64Kbps, and one D-Channel which carries call-control information. In contrast, BRI (Basic Rate Interface), which is designed for individuals and small businesses, contains just two B-channels and one D-channel. PRI service is generally transmitted through a T1 line (or an E1 line in Europe). A T1 line is a dedicated phone connection supporting data rates of 1.544Mbits per second. A T1 line actually consists of 24 individual channels, each of which supports 64Kbits per second. Each 64Kbit/second channel can be configured to carry voice or data traffic.
Although this is the preferred communication medium, the invention is not limited to any particular medium.
At step 120, the MSP 86 then sends the IN response message containing the destination Routing Number for terminating the call on the chosen PRI connected to the NAS 46. The response message also contains a "send notification" parameter that allows the MSP 86 to be notified after the call is torn down.
After receiving the IN response message from the MSP 86, the ingress end office switch 62 delivers the call to the destination Routing Number, that is, to the ISP 50 NAS 46 at step 122. At step 124, the NAS 46 then answers the call and goes through the user authentication process by sending a RADIUS Authentication-Request message to ISP's 50 own AAA server 82. Clearly, this processed can be changed accordingly if a different authentication method is used, or no authentication is performed at all.
The NAS 46 would then send a RADIUS Acct-Start message to the ISP's 50 AAA server 82 at step 126, authorizing the access. At step 128, the subscriber is now connected to the ISP 50 and will remain in this loop until he disconnects from the ISP 50.
When the subscriber disconnects, the ingress end-office switch sends a IN "terminate notification" to the MSP 86 over the SS7 network at step 130, and the ISP 50 generates an Automatic Messaging Account (AMA) record for the subscriber dial- in session, at step 132. An AMA record is a set of software features that provide billing information such as the control, collection, and recording of calls charged, and any other pertinent information required to record the calling and process the billing. Subsequent processing of this billing information may be processed periodically, such as monthly, but otherwise the teardown of the call is now complete.
While particular embodiments of the present invention have been shown and described, it is clear that changes and modifications may be made to such embodiments without departing from the true scope and spirit of the invention.
The method steps of the invention may be embodiment in sets of executable machine code stored in a variety of formats such as object code or source code. Such code is described generically herein as programming code, or a computer program for simplification. Clearly, the executable machine code may be integrated with the code of other programs, implemented as subroutines, by external program calls or by other techniques as known in the art.
The embodiments of the invention may be executed by a computer processor or similar device programmed in the manner of method steps, or may be executed by an electronic system which is provided with means for executing these steps. Similarly, an electronic memory medium such computer diskettes, CD-Roms, Random Access Memory (RAM), Read Only Memory (ROM) or similar computer software storage media known in the art, may be programmed to execute such method steps. As well, electronic signals representing these method steps may also be transmitted via a communication network.
The invention could, for example, be applied to computers, smart terminals, personal digital assistants and Internet-ready telephones. Again, such implementations would be clear to one skilled in the art, and do not take away from the invention.