Identifying phone calls for internet telephony feature handling by routing the phone calls to a softswitch via a dedicated trunk

A communication system includes a plurality of time division multiplexed (TDM) public switched telephone network (PSTN) trunks, a Signal Control Point (SCP), a Softswitch, and an Internet telephony call controller. The SCP a plurality of phone numbers for time division multiplexed TDM PSTN lines with an Internet telephony feature group that has Internet telephony feature handling. The SCP routes phone calls that are directed to phone numbers in the Internet telephony feature group through at least one dedicated trunk of the PSTN to the Softswitch. The Softswitch routes phone calls that it receives on the dedicated trunk to the Internet telephony call controller for Internet telephony feature handling.

BACKGROUND OF THE INVENTION

The present invention relates to communication networks and methods of operating the same, and, more particularly, to an overlay architecture for providing Internet telephony like features to time division multiplexed phones and methods of operating the same.

Internet telephony, also referred to herein as Voice-Over Internet Protocol (VoIP), Voice-Over Network (VoN), and/or Internet Protocol Telephony (IP Telephony), is becoming increasingly popular due, in part, to marked improvements in reliability and sound quality of the service. The improved performance of Internet telephony communications may be due to upgrades made to the Internet backbone through improved switching fabrics, such as Asynchronous Transfer Mode (ATM) fabrics, and to implementation of new communications standards, such as standards for transport protocols, directory services, and/or audio codec format.

Currently, to provide Internet telephony communications to a customer, a customer obtains equipment, such as Integrated Access Devices (IADs), Analog Terminal Adaptors (ATAs), telephone adapters (TAs), and the like, to be installed at the customer's premises, for example, a customer's home. The equipment is used to support a voice and control path within the premises and through a broadband network connection, for example, a digital subscriber line (DSL) connection, back to an Internet Service Provider (ISP). Once the necessary equipment is installed, customers/subscribers can connect their existing analog phones, for example, Plain Old Telephone Service (POTS) phones, to the ATA(s). The ATA(s) provide such functionality as dial tone, battery, and power ringing as part of providing POTS functionality through the VoN service. Normally, a Central Office (CO) switch provides dial tone, battery, and power ringing for analog phones.

Internet telephony technology can provide telephone users with features such as calling name and number, call management options, and the like. While some customers may desire such features, they may not have access to the required broadband network connection and/or may prefer to continue to use their analog phones with the reliable time division multiplexing (TDM) technology and powered by the CO, rather than acquire the customer premises equipment (CPE) to support Internet telephony service.

SUMMARY

Some embodiments of the present invention are directed to operation of communication system, which includes associating a plurality of phone numbers for time division multiplexed (TDM) public switched telephone network (PSTN) lines with an Internet telephony feature group that has Internet telephony feature handling. Phone calls that are directed to phone numbers in the Internet telephony feature group are routed through at least one dedicated trunk of the PSTN to a Softswitch. Phone calls received by the Softswitch on the dedicated trunk are routed to an Internet telephony call controller for Internet telephony feature handling.

Some other embodiments are directed to a Signal Control Point (SCP) within a PSTN. The SCP includes an Internet telephony feature controller that is configured to associate a plurality of phone numbers for TDM PSTN lines with an Internet telephony feature group that has Internet telephony feature handling. The Internet telephony feature controller is further configured to route phone calls that are directed to phone numbers in the Internet telephony feature group through at least one dedicated trunk of the PSTN to a Softswitch for routing to an Internet telephony call controller for Internet telephony feature handling.

Some other embodiments are directed to a Softswitch that includes an Internet telephony call router controller that is configured to receive phone calls on a plurality of trunks of a public switched telephone network (PSTN). The Internet telephony call router controller is further configured to decide whether to route individual ones of the phone calls through an Internet protocol (IP) network to an Internet telephony call controller for Internet telephony feature handling in response to whether the individual phone call was received by the Softswitch on a dedicated one of the trunks of the PSTN that is designated for carrying calls for Internet telephony feature handling.

DETAILED DESCRIPTION OF EMBODIMENTS

The present invention may be embodied as methods, electronic devices, and/or computer program products. Some embodiments may be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.). Consequently, as used herein, the term “signal” may take the form of a continuous waveform and/or discrete value(s), such as digital value(s) in a memory or register. Furthermore, as will be described below, various embodiments may take the form of a computer program product on a computer-usable or computer-readable storage medium having computer-usable or computer-readable program code embodied in the medium for use by or in connection with an instruction execution system.

Various embodiments of the present invention are directed to providing an Internet telephony (e.g., VoIP) overlay architecture for a PSTN so as to provide Internet telephony like features for customers who are using analog phones and/or other communication terminals to make and/or receive calls that are terminated through the PSTN using TDM technology. In accordance with some embodiments, Internet telephony like features can include, but are not limited to, displaying calling name and/or number of an entity associated with a calling phone line, call forwarding to one or more defined phone numbers, recording phone calls in a call log that is accessible by a subscriber, selectively allowing/blocking incoming phone calls based on a defined profile. For example, using Internet telephony features, a subscriber can define a call profile that will selectively allow/block phone calls within or outside defined time of day windows, defined days of the week windows, and/or which are included within or not-included within a defined phone number list(s).

One prior art approach to providing an Internet telephony overlay architecture for a PSTN used advanced intelligent network (AIN) call forwarding to map (port) customers' phone numbers, which were assigned to TDM trunks, to VoIP phone numbers, which were assigned to and handled by the Internet telephony overlay architecture.

According to this prior art approach, every TDM subscriber who was provided with Internet telephony feature handling was assigned a TDM phone number and a shadow IP phone number. When the TDM phone number was dialed, the phone call was intercepted, a mapping table was used to substitute the shadow IP phone number for the primary phone number, and the phone call was then routed through the PSTN to a Softswitch using the shadow IP phone number. The Softswitch identified from the shadow IP phone number that the phone call needed Internet telephony feature handling, and responded by converted the phone call into a VoIP call which it routed through an IP network to an Internet telephony call control complex.

Potential drawbacks of this prior art approach included the necessity for the communication system to maintain at least two phone numbers for every TDM subscriber which was provided with Internet telephony features. This approach could also result in increased complexity in the communication system in order to assign, maintain, and process the mapping between TDM phone numbers and shadow IP phone numbers and to provide compliance with regulatory provisions for number portability.

Referring now toFIG. 1, an exemplary communication system100, in accordance with some embodiments of the present invention, includes a PSTN112, a Softswitch120, and Internet telephony call control complex122. The PSTN102can include a PSTN switching system110with a plurality of TDM PSTN trunks, and a Signal Control Point (SCP)140. The Internet telephony call control complex122can include an Internet telephony call controller130, a subscriber Internet telephony feature repository132, and a subscriber interface server134.

In accordance with various embodiments of the present invention, the SCP140associates a plurality of phone numbers of the switching system110, i.e., certain called phone numbers, that have Internet telephony feature handling to a defined Internet telephony feature group. The SCP140routes phone calls that are directed to phone numbers in the Internet telephony feature group through at least one dedicated TDM trunk (e.g., dedicated trunk group)115, of the switching system110, to the Softswitch120. An Internet telephony call router controller122in the Softswitch120routes phone calls that are received on the dedicated trunk115to the Internet telephony call controller130for Internet telephony feature handling.

Because the dedicated trunk115of the switching system110may be used to only route phone calls to the Softswitch120for subsequent routing to the Internet telephony call controller130, the phone calls can be routed to the Softswitch120without needing to use shadow IP phone numbers. The Softswitch120therefore knows that any phone call that is received on the dedicated trunk115is to be routed to the Internet telephony call controller130. Moreover, the Softswitch120(e.g., via the Internet telephony call router controller122) can automatically convert all TDM phone calls it receives through the dedicated trunk115into VoIP phone calls that it routes to the Internet telephony call controller130, and without needing to carry-out other operations to determine whether or not to perform the conversion of such calls. Use of the dedicated trunk115can thereby avoid the Softswitch120needing to maintain and refer to a table that would identify which particular phone numbers are shadow IP phone numbers that are to suppose be routed to the Internet telephony call controller130.

The switching system110may include a Class 5 Switch, such as the 5ESS™ switch sold by Lucent Technologies, Inc. The switching system110may terminate thousands of analog phone lines, such as illustrated by the exemplary analog phone145. The switching system110forms a portion of the PSTN112, which includes many signaling networks, such as Common Channel Signaling (CCS) networks, and which can interface to other wireline/wireless switching systems (e.g. cellular/wireless network142) and. One such CCS network is the Signaling System 7 (SS7) network.

In an SS7 network, signaling messages are used to setup, manage, and release network resources to complete (terminate) calls/connections. The signaling traffic is carried by one or more Signal Transfer Points (STPs). An STP is typically embodied as a packet switch that routes each incoming message to an outgoing signaling link based on routing information contained in the SS7 message.

The SCP140can be configured to trigger Internet telephony feature handling (e.g., Intelligent Network (IN) services) for phone calls in the switching system110by communicating with the switching system110and the Softswitch120using special signaling messages.

As discussed above, the PSTN includes many wireline and wireless switching systems (e.g., systems110and142) that may terminate phone lines of varying types as represented by the analog phone145and the other phone150. Phone150may be, for example, an analog phone, digital phone, or mobile terminal. As used herein, the term “mobile terminal” may include a satellite and/or cellular radiotelephone, laptop computer, and/or palmtop computer that includes a radiotelephone transceiver.

At least one dedicated trunk115communicatively couples the switching system110and the Softswitch120. The Internet telephony call router controller122of the Softswitch120provides a communication gateway interface between the circuit-switched PSTN network112and the packet switched IP network170.

The Softswitch120in combination with the Internet telephony call control complex122can form part of an Internet telephony overlay network that can provide Internet telephony like features, which conventionally are provided to customers that have purchased Internet telephony (e.g., VoN) service and have installed the accompanying customer premises equipment (CPE), to customers that have an analog phone, such as the analog phone145. As understood by those of skill in the art in view of the present description, the Internet telephony call control complex122may include other servers and systems in addition to the controller130, the repository132, and the server134, such as, but not limited to, Network servers, Feature Servers, Web servers, Media servers, etc.

The Softswitch120may communicate with the Internet telephony call controller130using Session Initiation Protocol (SIP) messaging to establish communication sessions through the IP network170. SIP may be used to transport the converted VoIP phone call between the Softswitch120and the Internet telephony call controller130in IP data packets. In some embodiments of the present invention, the Internet telephony call controller130may run BroadWorks™ VoIP application software provided by the BroadSoft™ corporation of Gaithersburg Md. in combination with the Internet telephony feature controller144and the Internet telephony call router controller122to provide Internet telephony like features to a customer that uses the analog phone145and/or the other telephone150.

The functionality of various elements of the communication system100ofFIG. 1is described below with regard to the operational and communication timing diagram ofFIG. 2and the flowcharts ofFIG. 3-6. These figures further illustrate exemplary operation of the communication system100to provide Internet telephony like features to customers who are communicating through TDM lines of the PSTN112in accordance with various embodiments of the present invention.

FIG. 2is an exemplary operational and communication timing diagram of the communication system100ofFIG. 1.FIG. 3is a flowchart that illustrates exemplary operations of the switching system110. Referring toFIGS. 2 and 3, a Termination Attempt Trigger (TAT) function in the switching system110detects receipt (block202) of a phone call attempt to an analog TDM line of the switching system110(e.g. to the analog telephone145). Rather than terminate the call to the called line, the phone call is placed on hold (204) and the switching system110routes a request (206), such as a SS7 Transaction Capabilities Application Part (TCAP) query, to the SCP140for routing (termination) instructions.

FIG. 4is a flowchart that illustrates exemplary operations of the Internet telephony feature controller144within the SCP140(“SCP feature controller”). Referring toFIGS. 2 and 4, the SCP feature controller144identifies (block208) the called phone number as being associated with a defined Internet telephony feature group and, thereby, that the called phone number has Internet telephony overlay feature handling associated therewith that is to be provided by the Internet telephony call controller130. Responsive to that identification, the SCP feature controller144commands (communication210) the switching system110to route the phone call through the dedicated trunk115, or, when there are a plurality of dedicated trunks then commands routing through one of those dedicated trunks, to the Softswitch120(communication212). In contrast, when the called phone number is not associated with the Internet telephony feature group, the SCP feature controller144commands (block209) the switching system110to terminate the phone call to the called analog TDM line.

FIG. 5is a flowchart that illustrates exemplary operations of the Internet telephony call router controller122within the Softswitch120(“Softswitch router controller”). Referring toFIGS. 2 and 5, because the dedicated trunk115of the switching system110is used to only route phone calls to the Softswitch120that are intended for routing therethrough to the Internet telephony call controller130, the Softswitch router controller122therefore knows that any phone call that is received on the dedicated trunk115is to be routed to the Internet telephony call controller130.

Accordingly, in response to receiving a phone call on the dedicated trunk (block214a), the Softswitch router controller122automatically converts (block214b) the phone call to a VoIP (or other Internet telephony) phone call and routes (block216) the converted Internet telephony phone call to the Internet telephony call controller130. The Softswitch router controller122may route (block216) the converted VoIP phone call through the IP network170using SIP messaging.

FIG. 6is a flowchart that illustrates exemplary operations of the Internet telephony call controller130. Referring toFIGS. 2 and 6, in response to receiving (block216) the VoIP phone call from the Softswitch120, the Internet telephony call controller130generates (block218) a query (communication220) to the subscriber telephony feature repository132to determine what feature rules it should apply to the phone call. The feature repository132identifies (block222ofFIG. 2) applicable telephony feature rules in response to the called phone number and/or in response to the calling phone number, and provides a rules response (communication224ofFIG. 2) back to the call controller130.

The call controller130handles the phone call (block226) according to the Internet telephony features identified by the rules response from the feature repository132, and can generate a call control response that can be used by the SCP140to regulate termination of the phone call by the switching system110. For example, the call controller130may cause the calling name and/or number of the entity associated with a calling phone line trunk to be displayed (via the call control response228) on the called subscriber's phone (e.g.,145/150) and/or on another subscriber communication device, such as displayed in a pop-up window on the computer160. The call controller130may alternatively or additionally cause an instance of the phone call to be recorded in a call log, which may be stored in the call controller130and/or elsewhere in the control complex122, and where it is accessible to a subscriber, such as by using the computer162to log into the subscriber interface server134through the IP network170.

Alternatively or additionally, the call controller130can generate the call control response228so as to indicate that the phone call is to be allowed or blocked, and/or to indicate that the phone call is to be forwarding to one or more defined phone numbers (e.g., forwarded to a plurality of group-call phone numbers which may or may not include the called phone number) and/or to a voice mail service.

The feature repository132may contain rules that define a time of day window(s) (range between defined times) and/or days of the week window(s) when phone calls are either allowed or not allowed, and may further define a list of phone numbers that are allowed or not allowed either within or outside the defined windows. For example, phone calls from defined phone numbers may be allowed at any time on any day, while other defined phone numbers may not be allowed at any time/day, while still other defined phone numbers and/or phone numbers that are outside the defined list may be allowed only when they occur within the defined time of day window(s) and/or on the defined days of the week window(s).

A subscriber may define rules in the feature repository132that are used to provide Internet telephony feature handling for phone calls to one or more trunks assigned to the subscriber. For example, subscriber may use the computer162to log into the subscriber interface server134through the IP network170, and then use applications hosted on the subscriber interface server134to define/modify one or more of the rules of the feature repository132. The subscriber may thereby identify what phone calls are allowed/blocked, define whether and how phone calls are to be logged, define when and how phone calls are be forwarded to what phone number(s), and/or define the time of day window(s) and/or days of the week window(s) when phone call through their allowed or not allowed.

The Softswitch120responds to the call control response228by generating (block230) a call control routing response (communication232) that reroutes the phone call back to the switching system110. The switching system110responds to the return phone call by generating another routing request (communication234) to the SCP140. The SCP140response thereto by generating a call routing response (block236) that regulates (block238) call termination by the switching system110so as to carry out the identified Internet telephony call handling. For example, the SCP140can regulate the switching system110to complete termination of the phone call to the called phone number line, to block termination of the phone call to the called phone number line, and/or to complete termination of the phone call to a plurality of identified phone number lines.

Accordingly, the communication system100provides Internet telephony like features for customers who are using analog phones and/or other communication terminals to make and/or receive calls that are terminated through the PSTN using TDM technology. The communication system100may reduce the complexity of the SCP140and/or complexity of the Softswitch120, and/or may reduce/eliminate the need for shadow IP phone numbers to provide an Internet telephony overlay architecture, by using one or more dedicated trunks (e.g., trunk115) to route phone calls from the PSTN112to the Softswitch120for subsequent routing to the Internet telephony call control complex122for Internet telephony feature handing.

The flowcharts and timing diagrams ofFIGS. 2-6illustrate exemplary architecture, functionality, and operations of embodiments of methods, systems, and/or computer program products for operating a communication system so as to provide Internet telephony features. In this regard, each block represents a module, segment, or portion of code, which comprises one or more executable computer program instructions and/or hardware operations for implementing the specified logical function(s). It should also be noted that in other implementations, the function(s) noted in the blocks may occur out of the order noted inFIGS. 2-6. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending on the functionality involved.

These computer program instructions may be executed by a processor of a general purpose computer, a special purpose computer, or other programmable data processing apparatus to produce a machine that carries out at least some of the functionality described herein with regard to various embodiments of the present invention. These computer program instructions may also be stored in a computer-usable or computer-readable medium that may direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-usable or computer-readable medium produce an article of manufacture including instructions that implement the function specified in the flowchart and/or block diagram block or blocks.

The computer-usable or computer-readable medium may be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, or semiconductor system, apparatus, or device configured to at least temporarily store data. More specific examples (a nonexhaustive list) of the computer-readable medium would include the following: a magnetic memory (e.g., disk drive/diskette), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), and a compact disc/digital video disk read-only memory (CD/DVD-ROM).

Many variations and modifications can be made to the embodiments without substantially departing from the principles of the present invention. All such variations and modifications are intended to be included herein within the scope of the present invention, as set forth in the following claims.