ROUTING TOLL-FREE TELECOMMUNICATIONS TRAFFIC OVER
DATA NETWORKS
5 l. Technical Field
This application relates to the field of telecommunications and data networks, and more particularly to the field of routing toll-free telecommunications traffic over data networks.
2. Background l o Using toll-free numbers, a caller may place a telephone call without incurring the costs associated therewith. In the United States, toll free numbers are generally signaled by using an exchange, such as 8oo, 888, or 877, before a seven-digit telephone number. Within these exchanges, a call recipient bears the costs of a call, and the caller generally is not billed,
15 regardless of the geographic separation between parties and the duration of the call.
Conventional toll-free calls may have a number of commercial entities involved in provisioning the call. If the subscriber, i.e., the party receiving toll-free calls, has a dedicated connection to an Inter-Exchange Carrier 20 ("IXC"), then the toll-free call is provided by a Local Exchange Carrier ("LEG") originating the call, and the IXC. The subscriber may instead use switched toll-free service, where a terminating LEG is used to connect a call between the IXC and the subscriber.
Typically, a call will be placed to an LEG, which may use a Signaling 25 System 7 ("SS7") network to access a database for translating a toll-free number into a "real" number that is used the by telecommunications network to route the call. The LEC may then connect the call to the IXC, which transports the call to a suitable switch - either a circuit to a subscriber's customer premises equipment ("CPE") such as a Private Branch
Exchange ("PBX"), or a terminating LEC that handles the call in a conventional fashion.
As a significant disadvantage, these toll-free calling systems require activity by several different entities, which results in substantial charges to a subscriber. A database access charge may be incurred for each SS7 access to the toll-free number database. A metered charge may be incurred from the originating LEC. A transport charge may be incurred from the IXC. A fixed monthly charge may be incurred from the IXC for providing the toll- free circuit(s). Finally, in the case of switched toll-free service, a metered charge may be incurred from the terminating LEC.
There remains a need for a toll-freecalling system that alleviates costs to a toll-free number subscriber.
Summary
A system according to the principles of the invention provides toll-free calling that transports calls using a data network such as the Internet. One or more gateways may be provided to transfer incoming call traffic from LECs to a data network. Calls may then be transportedover the data network using any suitable addressing technique, such as Internet Protocol ("IP") addresses. A receiving node on the data network may connect incoming call traffic directly to a toll-free call center, or the receiving node may connect to a second LEC which can connect incoming calls to a toll-free subscriber or a toll-free call center.
Brief Description Of Drawings
The foregoing and other objects and advantages of the invention will be appreciatedmore fully from the foUowingfurther descriptionthereof , with reference to the accompanying drawings, wherein:
Fig. 1 is a block diagram of a switched toll-free service for personal use according to the principles of the invention;
Fig. 2 is a flow chart showing a process for providing personal toll-free service according to the principles of the invention;
Fig. 3 is a block diagram of a toll-free call center according to the principles of the invention; and Fig. 4 is a flow chart showing a process for providing a toll-free call center according to the principles of the invention.
Detailed Description
To provide an overall understanding of the invention, certain illustrative embodiments will now be described, including a system for routing toll-free calls through a data network. However, it will be understoodby those of ordinary skill in the art that the methods and systems described herein can be suitably adapted to any network or combination of networks capable of transporting data at speeds consistent with telephony. The principles of the invention are particularly applicable to those environments where a data network can provide a lower-cost alternative to existing toll-free services, and to those environments where call routing includes LEC access to a database for number translation, such as local number portability.
Fig. l is a block diagram of a switched toll-free service for personal use according to the principles of the invention. A system 100 according to the invention includes a phone 102, a first LEC 104, a toll-free number translation database 106, a gateway 108, a telecommunications network 110, a data network 112, a second LEC 114, a second gateway 116, a third gateway 118, a toll-free network server 120, a fourth gateway 122, a third LEC 124, a subscriber 126, and a VoIP gatekeeper 128. As will be described below, the system 100 operates generallyto receive an incoming toll-freecall from the phone 102, and to route the incoming toll-free call from the phone 102 to the subscriber 126 through the data network 112.
The phone 102 originates an incoming toll-free call by, for example,
dialing a toll-free number from a conventional telephone. This is presented as a call request to the first LEC 104. It will be appreciated that the first LEC 104, and the other LEC's referred to herein, may be any carrier capable of receiving incoming calls from local subscribers, includingany local exchange carrier, a competitive local exchange carrier, an incumbent local exchange carrier, or the like. It will further be appreciated that the phone 102 may instead be a wireless telephone such as a cellular handset using Global System for Mobile Communications ("GSM"), Code Division Multiple Access ("CDMA"), Time Division Multiple Access ("TDMA"), Personal Communications Service ("PCS"), or any other wireless standard for communicating with a wireless base station, which may in turn connect to the Public Switched Telephone Network ("PSTN"). Any wireless or wired telephone and phone service is intended to be includedwithin the scope of the invention described herein.
Where the call origination includes a toll-free exchange, such as 800,
888, 877, and so forth, the first LEC 104 may access the toll-free number translation database 106 to obtain exchange and local dialing numbers for call routing of the toll-free call. For example, where the first LEC includes a Signal Service Point ("SSP") according to the Signaling System 7 ("SS7") protocol, and the toll-free number translation database 106 includes a Service Control Point ("SCP"), a databaseinquirymaybe performed through a message to the SCP using the Transaction Control Application Part ("TCAP") layer of the SS7 protocol. It will be appreciated that any number lookup system may be used with the invention provided that it can respond to a request from the first LEC 104 with dialing or routing information for a toll-free service.
The toll-freenumber translation databaseio 6 may maintain a one-to- many relationship with a toll-free number and "real" numbers or addresses associated therewith. The toll-free number translation database 106 may return, for example, an address or phone number for the first local exchange
carrier 104 to reach the gateway 108, or the toll-free number translation database 106 may return a number for the second LEC 114, which includes the second gateway 116 for accessing the data network 112. The first LEC 104 may connect a call to the second LEC 114 through, for example, the PSTN or any other network. The toll-free number translation database 106 may optionally return a local exchange number for the subscriber 126, where, for example, the subscriber 126 shares a local exchange with the phone 102 that originated the toll-free call.
The gateway 108 may connect calls from the first LEC 104 through the data network 112. Although shown in Fig.1 as a single component of the personal toll-free system 100, it will be appreciated that the gateway 108 may include, for example, two components that maybe at a single location, or at remote locations connected in a communicating relationship. A first component may be a competitive local exchange carrier ("CLEC") or other telecommunications system connected to the first LEC 104. A second component may be a data network point-of-presence connected in a communicating relationship with the data network 112. The gateway 108 may include an interface between these two components, the interface converting signals between a form suitable for the PSTN and a form suitable for the data network 112. The gatewayioδ may, for example, transfer voice traffic or other calls using a proprietary protocol, a standard such as H.323 or Media Gateway Control Protocol ("MGCP"), or any other format suitable for transmitting voice over the data network 112. The gateway 108 may have one or more Internet Protocol ("IP") addressesfor sending and receiving data over the data network 112. The interface between the data network point-of-presence and the CLEC may include, for example, an Integrated Services Digital Network ("ISDN") Primary Rate Interface ("PRI") connection, or, where traffic is backhauled, ISDN PRI encapsulated in Ti.
The gateway 108 may include a processor and memory, such as a computer or server. The processor maybe programmed to control operation
of the gateway 108, and to perform operations associated with the gateway 108. For example, the processor may operate as a translator, for example performing translations between voice traffic carried over the PSTN and voice traffic carried over the data network 112. The processor may also control connections to the data network 112 and the LEC 104, etc. The gateway 108 may similarly performany other functions required to connect voice traffic on one hand, and data network traffic on the other. This may include hardware and/ or software for coding and decoding voice traffic, adaptations of signaling information, communication of call setup and tear down information between PSTN representations^. g., analog or digital local loop) and, for example H.323 representations, and so forth.
The gateway may also execute flow control for calling through the system 100, using, for example, software executing on the processor. Flow control may include, for example, managing connections to the gatekeeper to obtain addresses of other gateways in the system 100, or maintaining persistence of a call with the first LEC 104 while .
The telecommunications network 110 may be, for example, the PSTN or any other network suitable for circuit-switched or other telecommunications traffic. The data network 112 may be the Internet or any other network suitable for packet-switched or other data traffic.
As noted above, where no gateway to a data network is available from the first LEC 104, such as the first gateway 108 to the data network 112, the toll-free number translationdatabase 106 may returna number ofa suitable exchange that can be reached through the telecommunicationsnetwork 110, such as the second LEC 114. Where a number of suitable exchanges are available, the toll-free number translation database 106 may provide a suitable exchange according to cost, physical distance, gateway loading, or any other criteria. The second gateway 116 may be, for example, a gateway similar to the firstgateway 108. As shown in Fig.1, the toll-free call may be
transported through the telecommunication network no directly to the third LEC 124, where, for example, no gateway is available to the first gateway 108.
A toll-free call that is being connected through the data network 112 may first be routed to the toll-free network server 120. For example, an incoming call being routed through the first gateway 108 or the second gateway 116 may be routed to the toll-free network server 120 through the third gateway 118, using, for example, the IP address of the third gateway 118. The IP address ofthethird gateway 118 maybe known to the gateway 108, 116 handling the incoming call, or the IP address of the third gateway
118 may be determined through a request to the VoIP gatekeeper 128. The connection between the third gateway 118 and the toll-free network server
120 need not include any exchange or other telecommunications network components. The third gateway 118 may, nonetheless provide services for communicating with other gateways within the system 100, such as H.323 or other Voice-over-IP protocols. It will be appreciated that a number of toll- free network servers 120 may be provided according to the principles of the invention, and that access to a particular one of the toll-free network servers 120 may be determined according to proximity to the gateway handling an incoming call, load balancing among the servers, or some other criteria.
Where the incoming call is directed to a toll-free number for a unique subscriber, the toll-free network server 120 may return gateway (i.e., data network) and exchange (i.e., telecommunications network) information for connecting the phone 102 to the subscriber 126, and the call may be completed directly.
The incomingcallmay optionally containa number for a personal toll- free service managed by the toll-free network server 120. In this case, the toll-free network server 120 may include an Interactive Voice Response ("IVR") system which prompts a user at the phone 102 to identify a call
destination. The call destination may be indicated by a seven or ten digit calling number, an identification number of any length, or by a name of a receiving party. Data may be entered using, for example, dual-tone multi- frequency signaling or voice recognition software running on the toll-free 5 network server 120. The toll-free network server 120 may also provide a human operator to assist in placing a call.
When a call destination has been identified, information for call setup over the data network 112 may be returned to the first gateway 108 (or the second gateway 116 if this is the source of the call) using, for example, H.450 0 or H.323 call setup capabilities. Addressing information used to connect gateways may be provided by the toll-free network server 120. Optionally, the VoIP gatekeeper 128 may be accessed by the first gateway 108, and the VoIP gatekeeper 128 may provide any routing information required to complete a call setupbetween two gateways over the data network 112. The 5 first gateway 108 may then establish a connection to the fourth gateway 122 .
The fourth gateway 122 may receive call setup information from, for example, the first gateway 108, and complete a call request to the subscriber 126 through the third LEC 124. The subscriberi26 is responsive to the call o request as a conventional telephone. The incoming call may be indicated at the subscriber 126 through any technique, including conventional ringing, flashing, or vibration ring indicators. If the subscriber 126 answers the incoming call, voice communication may be conducted between the phone 102 and the subscriber 126, as connected through the first LEC 104, the first 5 gateway 108, the data network 112, thefourth gateway 122, and the third LEC 124.
Optionally, the toll-free number translation database 106 may have sufficient capacity to store full calling information foreach personal toll-free service subscriber 126. In this case, a call may be completed by simply
accessing the toll-free number translation database 106 from the first LEC 104, and receiving in return informationfor completing the call through the first gateway 108, the data network 112, the fourth gateway 122, and the third LEC 124, without an intermediate access to the toll-free network server 120. In anotherconfiguration,the toll-freenumbertranslationdatabaseιo 6 may be configured to access the toll-free network server 120, either through a public network or a private network, to obtain some or all of the information required to setup a toll-free call between the phone 102 and the subscriber 126.
Figure 2 is a flow chart showing a process for providing personal toll- free service according to the principles of the invention. The process 200 begins when an incoming toll-free call is received at an LEC, as shown in step 202. As shown in step 204, the LEC accesses a database, such as the toll-free number translation database 106 of Fig. 1, to resolve the toll-free number into dialing information for a toll-free subscriber. This number may be a numberfor a gatewayto a datanetwork, such as the first gateway 108 orthe second gateway 116 of Fig. 1.
As shown in step 206, if a gateway is accessible from the LEC, then the
LEC connects the call to that gateway and the process 200 proceeds to step 208. If a gateway is not accessible from the LEC, then the LEC connects the call to another LEC that does have access to a gateway, as shown in step 210.
The process 2 o o m a y then proceed to step 208.
Once the call is connected to a gateway, a subscriber gateway address may be resolved, as shown in step 208. This may include accessing a server such as the toll-free network server 120 of Fig. 1, and prompting a caller to provide identifying information for a toll-free subscriber. The server may then provide an address and other information for a gateway that shares an LEC with the toll-free subscriber and the call may be connected to that gateway.
As shown in step 212, a determination may be made whether the toll- free subscriber is within the same local calling area as the originator of the call, e.g., if the subscriber and the originator share an LEC. If the call is a local call, then the subscriber and the originator may be connected through the LEC, as shown in step 214.
If the call is not a local call, then the gateway that received the call is connected to a gateway for the subscriber, as shown in step 218. When the gateways are connected to carry a call, dialing information for the subscriber may be transmitted to an LEC local to the subscriber. The phone call may then be completed through the LEC, as shown in step 16.
Fig. 3 is a block diagram of a toll-free call center according to the principles of the invention. A system 300 accordingto the invention includes a phone 302, a first LEC 304, a toll-free number translation database 306, a gateway 308, a telecommunications network 310, a data network 312, a second LEC 314, a second gateway 316, a third gateway 322, a call center 324, and a NoIPgatekeeper328. As will be described below, the system 300 operates generally to receive an incoming toll-free call from the phone 302, and to route the incoming toll-free call from the phone 3 o 2 to the call center 324 through the data network 312.
The phone 302 originates an incoming toll-free call by, for example, dialing a toll-free number from a conventional telephone. This is presented as a call request to the first LEC 304. It will be appreciated that the first LEC 304, and the other LEC's referred to herein, may be any carrier capable of receiving incomingcalls from local subscribers, includingany local exchange carrier, a competitive local exchange carrier, an incumbent local exchange carrier, or the like. It will further be appreciated that the phone 302 may instead be a wireless telephone such as a cellular handset using GSM, CDMA, TDMA, PCS, or any other wireless standard for communicating with a wireless base station, which may in turn connect to the Public Switched
Telephone Network ("PSTN"). Any wireless or wired telephone and phone service is intended to be included within the scope of the invention described herein.
Where the call origination includes a toll-free exchange, such as 800, 888, 877, and so forth, the first LEC 304 may access the toll-free number translation database 306 to obtain exchange and local dialing numbers for call routing of the toll-free call. For example, where the first LEC includes a Signal Service Point ("SSP") according to the Signaling System 7 ("SS7") protocol, and the toll-free number translation database 306 includes a Service Control Point ("SCP"), a databaseinquiry may be performed through a message to the SCP using the Transaction Control Application Part ("TCAP") layer of the SS7 protocol. It will be appreciated that any number lookup system may be used with the invention provided that it can respond to a request from the first LEC 304 with dialing or routing information for a toll-free service.
The toll-freenumber translation database 306 may maintain a one-to- many relationship with a toll-free number and "real" numbers or addresses associated therewith. The toll-free number translation database 306 may return, for example, an address or phone number for the first local exchange carrier 304 to reach the gateway 308. The toll-free number translation database 306 may optionally return a number for connecting to the call center 324 through the PSTN. The toll-free number translation database 306 may optionallyreturn a local exchange number for the call center324, where, for example, the call center 324 shares a local exchange with the phone 302 that originated the toll-free call.
The gateway 308 may connect calls from the first LEC 304 through the data network 312. Although shown in Fig.3 as a single component of the toll-free system 300, it will be appreciated that the gateway 308 may include, for example, two components that may be at a single location, or at
remote locations connected in a communicating relationship. A first component may be a competitive local exchange carrier ("CLEC") or other telecommunications system connected to the first LEC 304. A second component may be a data network point-of-presence connected in a communicating relationship with the data network 312. The gateway 308 may include an interface between these two components, the interface converting signals between a form suitable for the PSTN and a form suitable for the data network 312. The gateway3θ8 may, for example, transfer voice traffic or other calls using a proprietary protocol, a standard such as H.323 or MGCP, or any other format suitable for transmitting voice over the data network3i2. The first gateway 308 may have one or more Internet Protocol ("IP") addresses for sending and receiving data over the data network 312. The interf acebetween the data network point-of-presenceand the CLEC may include, for example, an Integrated Services Digital Network ("ISDN") Primary Rate Interface ("PRI") connection, or, where traffic is backhauled, ISDN PRI encapsulated in Ti. In addition, although not shown in Fig. 3, the first gateway 308 may include a separate connection (i.e., not through the data network 112) to the VoIP gatekeeper 328, so that the VoIP gatekeeper may provide data networking address information to the first gateway 308 concerning other toll-free gateways connected to the data network 312.
The telecommunications network 310 may be,, for example, the PSTN or any other network suitable for circuit-switched or other telecommunications traffic. The data network 312 may be the Internet or any other network suitable for packet-switched or other data traffic.
As noted above, where no gateway to a data network is available from the firstLEC 304, such as thefirstgateway 3o8 to the data network 312, the toll-free number translation databases 06 may return a number of a suitable exchange that can be reachedthrough the telecommunicationsnetwork310 , such as the second LEC 314. Where a number of suitable exchanges are available, the toll-free number translation database 306 may provide a
suitable exchange according to cost, physical distance, gateway loading, or any other criteria. For example, where a company maintains a number of geographically distributedcall toll-freecall centers 324, the toll-free number translation database 306 may choose a most cost effective call center 324 for a particular call, such as a call center 324 within the same state, a call center 324 within the same exchange area, etc.
The second gateways 16 may operate in a fashionsimilartothe second gateway 116 of Fig.1. That is, the secondgateway 316 may connect through the third gateway 322 to the call center 324 in order to reduce long haul network usage such as inter-exchange carriers, and associated costs. In the system 300 of Fig.3, the second gateway 316 may also, or instead, function to connect the phone 302 to the second LEC 314, and in turn to provide a local, switched connection to the call center 324. In this manner, the call center 324 may provide switched toll-free service without associated costs such as inter-exchange carrier fees.
A toll-free call that is being connected through the data network 312 may instead be connected through a third gateway 322 directly to the call center equipment at the premises of the call center 324, such as a call center private branch exchange.
Optionally, the VoIP gatekeeper 328 may be accessed by the first gateway 308, and the VoIP gatekeeper 328 may provide any routing information required to complete a call setup between the first gateway 308 and the second or third gateway 316, 322 over the data network 312.
The third gateway 322 may receive call setup information from, for example, the firstgateway 308, and complete a call requestto the call center
324 through the third gateway322, or through the secondgateway 316 and the second LEC 314. The incoming call may be handled at the call center using any techniques, and may, for example, forwarded to a NRI system at
the call center 324, or placed into a queue for attention by an available operator.
Optionally, the toll-free number translation database 306 may have sufficient capacity to store full calling information for each call center 324. 5 In this case, a call may be completed by simply accessing the toll-free number translation database 306 from the first LEC 304, and receiving in return information for completing the call through the first gateway 308, the data network 312, and the third gateway 322.
Fig. 4 is a flow chart showing a process for providing a toll-free call 0 center according to the principles of the invention. The process 400 begins when an incoming toll-free call is received at an LEC, as shown in step 402.
An access is made to a toll-freenumber translation database, as shown in step
404.
As shownin step 406, where a gatewayisnot accessibletothe LEC, the 5 process 400 proceeds to step 408 where the toll-free call may be connected to a call center through the PSTN or some other telecommunications network.
If a gateway is accessible, an address may be resolved for a call center gateway, as shown in step 410. This may include, for example access to the VoIP gatekeeper 328 of Fig. 3. As shown in step 412, the call may then be o connected to, for example, the second gateway 316 or the third g ateway 322, depending on whether the call center provides switched service through an LEC, or direct service through a gateway to the data network.
If the toll-free call center uses switched service, then the call is connected through a gateway to an LEC, as shown in step 414. In this 5 configuration, the call center may maintain a conventionalconnectiontothe
LEC. If the toll-freecall center uses a network connection, then the call center
equipment may be connected directly to a gateway, such as the third gateway 322 of Fig.3. Thegatewaymay be configured to arbitratebetween a protocol used to transport calls over the data network and a protocol used by the premises equipment, such as a private branch exchange, of the call center.
While the inventionhasbeen disclosedin connection with the preferred embodiments shown and described in detail, various modifications and improvements thereon will become readily apparent to those skilled in the art. It should be understood that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative, and not in a limiting sense.