APPARATUS, SYSTEMS AND METHODS FOR SELECTIVELY CONNECTING AUTOMATICALLY-REJECTED TELEPHONE CALLS
TECHNICAL FIELD OF THE INVENTION The present invention is directed, in general, to communications systems and, more specifically, to apparatus, systems and methods for selectively connecting automatically-rejected telephone calls.
BACKGROUND OF THE INVENTION The world is currently experiencing revolutionary changes in communications systems, including the capability of such systems to provide advanced Intelligent Network (IN) services. IN services refers generally to a collection of services offered to telephony system subscribers on a pre-subscribed basis, such as Calling Number Delivery, or "Caller ID." Caller ID service automatically provides the telephone number and name of a calling party to a called party's telephone, where it can be displayed to the called party prior to answering the call. The called party can decide whether to answer the call based on the identity of the calling party. It is possible, however, that a called party that is subscribed to the Caller ID service may not automatically receive a calling party's telephone number and name if the calling party "blocks" their number and name, or if the calling party is located in a service area that does not support the Caller ID service.
In combination with the Caller ID service, a user can also subscribe to an IN service called "Anonymous/Unavailable Call Rejection," which prevents the connection of a call to a subscriber's telephone if the calling party has blocked the transmission of their telephone number or if they are calling from an area that does not support Caller ID. In such cases, the calling party hears an announcement informing them, for example, that the called party is not accepting calls from anonymous callers. If a call is rejected, the called party is never aware that the call was rejected. In some instances, however, it may not be desirable for a call to be rejected if the identity of the calling party is not automatically provided by the telephony system.
Accordingly, there is a need in the art for apparatus, systems and methods for providing an Intelligent Network (IN) service to selectively connect automatically-rejected telephone calls; preferably, such IN service should be easily implemented using existing communications system infrastructures.
SUMMARY OF THE INVENTION
To address the above-discussed deficiencies of the prior art, the present invention provides apparatus, systems and methods related to controlling the connection of automatically-rejected telephone calls to a called party telephony device subscribed to a selective call rejection feature. An exemplary method according to the principles of the present invention includes the steps of: i) receiving a device identifier in association with a call request from a calling party telephony device to a called party telephony device; ii) playing a pre-recorded announcement to the calling party telephony device if the device identifier is equivalent to predefined criteria; iii) receiving user input data from the calling party telephony device; and, iv) processing the call request as a function of the user input data.
The predefined criteria can be selected, for example, from the group consisting of "No ID," "Anonymous," "Unavailable," "Private," and "Blocked." In one embodiment, if the user input data from the calling party is equivalent to an identifier pre-selected by a subscriber associated with the called party device, the calling party telephony device is connected to the called party telephony device. In related embodiments, the user input data from the calling party can be substituted for the device identifier, and a distinctive ring that is a function of the user input data can be used, when the calling party telephony device is connected to the called party telephony device. An exemplary system in which the principles of the present invention can be implemented includes a Service Switching Point (SSP), and a Service Control Point (SCP) coupled to the SSP; SSPs and SCPs can be network nodes within a Signaling System 7 (SS7) communications network. An SSP is operative to route a call request from a calling party telephony device having a device identifier to a called party telephony device. An
SCP is operative to: i) receive the device identifier; ii) instruct the SSP to direct a prerecorded announcement to the calling party telephony device if the device identifier is equivalent to predefined criteria; ii) receive user input data from the calling party telephony device; and, iii) cause the SSP to process the call request as a function of the user input data.
User input data can be numeric data, alphabetic data, and/or alphanumeric data. In an exemplary embodiment, if the user input data is equivalent to an identifier preselected by a subscriber associated with the called party device, the SCP can instruct the SSP to connect the call request to the called party telephony device. In a related embodiment, the SCP can also instruct the SSP to substitute the user input data for the calling party device identifier when connecting the call request to the called party telephony device; the called party can decide whether to answer the call based on the received user input data. In a further related embodiment, the SCP can also instruct the SSP to use a distinctive ring that is a function of the user input data when the SSP connects the call request to the called party telephony device.
The foregoing has outlined, rather broadly, the principles of the present invention so that those skilled in the art may better understand the detailed description of the exemplary embodiments that follow. Those skilled in the art should appreciate that they can readily use the disclosed conception and exemplary embodiments as a basis for designing or modifying other structures and methods for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.
BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the present invention, reference is now made to the following detailed description taken in conjunction with the accompanying drawings, in which:
FIGURE 1 illustrates various signaling points, or network elements, and signaling link types of an SS7 network;
FIGURE 2 illustrates a functional schematic of an exemplary system employing the principles of the present invention; and
FIGURE 3 illustrates a flowchart of an exemplary method according to the principles of the present invention.
DETAILED DESCRIPTION
In order to better understand the features and advantages of the present invention, the basic structure and capabilities of the signaling network associated with the Public Switched Telephone Network (PSTN) is first described. Associated with the North American PSTN is a signaling network that employs the Common Channel Signaling System 7 (SS7) to exchange signaling messages between network elements, or "nodes." SS7 is a global standard for telecommunications defined by the International Telecommunications Union (ITU) Telecommunications Standardization Sector (ITU-T). The standard defines the procedures and protocol by which network elements, or nodes, in the Public Switched Telephone Network (PSTN) exchange information over a digital signaling network to effect wireless (e.g., cellular) and wireline call setup, routing and control. The ITU definition of SS7 allows for national variants such as the American National Standards Institute (ANSI) and Bell Communications Research (Bellcore) standards used in North America and the European Telecommunications Standards Institute (ETSI) standard used in Europe. The SS7 network and protocol are used for i) basic call setup, management, and tear down; ii) wireless services such as personal communications services (PCS), wireless roaming, and mobile subscriber authentication; iii) local number portability (LNP); toll-free (800/888) and toll (900) services; iv) enhanced call features such as call forwarding, calling party name/number display, and three-way calling; and v) efficient and secure worldwide communications.
Referring to FIGURE 1, illustrated are the various signaling points, or network elements, and signaling link types of an SS7 network. SS7 messages are exchanged between network elements, or nodes, over bi-directional channels called signaling links. Signaling occurs out-of-band on dedicated channels rather than in-band on voice channels.
Compared to in-band signaling using multi-frequency (MF) signaling tones, out-of-band signaling provides faster call setup times, more efficient use of voice circuits, support for Intelligent Network (IN) services which require signaling to network elements without voice trunks (e.g., database systems), and improved control over fraudulent network usage. Each network node, or signaling point, in the SS7 network is uniquely identified by a numeric point code. Point codes are carried in signaling messages exchanged between signaling points to identify the source and destination of each message; a message source has an Originating Point Code (OPC) and the destination of the message is identified by a Destination Point Code (DPC). Each signaling point uses a routing table to select the appropriate signaling path for each message.
As shown in Figure 1, there are three kinds of signaling points in an SS7 network; Service Switching Points (SSPs), Signal Transfer Points (STPs) and Service Control Points (SCPs). SSPs are switches that originate, terminate, or tandem calls. An SSP sends signaling messages to other SSPs to setup, manage, and release voice circuits required to complete a call. An SSP may also send a query message to a centralized database (e.g., an SCP) to determine how to route a call (e.g., a toll-free 800/888 call in North America). An SCP sends a response to the originating SSP containing the routing number(s) associated with the dialed number. An alternate routing number may be used by the SSP if the primary number is busy or the call is unanswered within a specified time. Actual call features vary from network to network and from service to service.
Network traffic between signaling points may be routed via a packet switch called an STP. An STP routes each incoming message to an outgoing signaling link based on routing information contained in the SS7 message. Because it acts as a network hub, an STP provides improved utilization of the SS7 network by eliminating the need for direct links between all signaling points.
Because the SS7 network is critical to call processing, SCPs and STPs are usually deployed in mated pair configurations in separate physical locations to ensure network- wide service in the event of an isolated failure. Links between signaling points are also provisioned in pairs, often referred to as a "linkset." Traffic is shared across all links in a
linkset; if one of the links fails, the signaling traffic is rerouted over another link in the linkset. The SS7 protocol provides both error correction and retransmission capabilities to allow continued service in the event of signaling point or link failures.
Signaling links are logically organized by link type, identified in FIGURE 1 as "A" through "F," according to their use in the SS7 signaling network. An access, or "A," link connects a signaling end point (e.g., an SCP or SSP) to an STP; only messages originating from or destined to the signaling end point are transmitted on an "A" link. A bridge, or "B," link connects an STP to another STP. Typically, a quad of "B" links interconnect peer (or primary) STPs (e.g., the STPs from one network to the STPs of another network). The distinction between a "B" link and a "D" link (described hereinafter) is rather arbitrary; for this reason, such links may be referred to as "B/D" links. A cross, or "C," link connects STPs performing identical functions into a mated pair. A "C" link is used only when an STP has no other route available to a destination signaling point due to link failure(s). SCPs may also be deployed in pairs to improve reliability; unlike STPs, however, mated SCPs are not interconnected by signaling links. A diagonal, or "D," link connects a secondary (e.g., local or regional) STP pair to a primary (e.g., inter-network gateway) STP pair in a quad-link configuration. Secondary STPs within the same network are connected via a quad of "D" links. An extended, or "E," link connects an SSP to an alternate STP. "E" links provide an alternate signaling path if an SSPs "home" STP cannot be reached via an "A" link. "E" links are not usually provisioned unless the benefit of a marginally higher degree of reliability justifies the additional expense. Lastly, a fully associated, or "F," link connects two signaling end points (i.e., SSPs and SCPs).
Having generally described the general features of the SS7 network associated with a PSTN, the novel principles of the present invention can be described. Turning now to FIGURE 2, with continuing reference to FIGURE 1, illustrated is a functional schematic of an exemplary system 200 employing the principles of the present invention; the exemplary system 200 can be implemented using the conventional infrastructure of a SS7 network as described previously.
As shown in FIGURE 2, a calling party telephony device uses the resources of the PSTN when placing a call to a called party telephony device. The PSTN includes an SSP 210 and a SCP 220 that facilitate the routing of the call. When a call request for the called party telephony device arrives at SSP 210, a terminating trigger, defined in TR-NWT- 001284, incorporated herein by reference, initiates the sending of a Termination Attempt message to the SCP 220. The Termination Attempt message includes the identity of the called party telephony, which is used by the SCP 220 to determine the services subscribed to by the called party. The Termination Attempt message also includes the identification of the calling party telephony device, if available, or an indication that the identity of the calling party is not available. If the identification of the calling party telephony device is available, call processing is handled in a conventional manner known to those of skill in the art; otherwise, call processing is preferably handled according to the principles of the present invention.
As previously described, if the identity of a calling party is not available when a call is placed to a called party device subscribed to an Anonymous/Unavailable Call Rejection service, the calling party will hear an announcement informing them, for example, that the called party is not accepting calls from anonymous callers. If a call is rejected, the called party is never aware that the call was rejected. According to the principles disclosed herein, however, if the identity of the calling party device is not available, a process is performed that may allow the routing of the call request to the called party telephony device, thereby overriding the conventional result associated with the Anonymous/Unavailable Call Rejection service.
The identity of the calling party may not be available if the calling party "blocks" their number and name, or if the calling party is located in a service area that does not support the Caller ID service - in such cases, the caller "identity" may be indicated, for example, as "No ID," "Anonymous," "Unavailable," "Private," or "Blocked." This indication is provided to the SCP 220 by the Termination Attempt message. According to the principles of the present invention, a new service function, referred to herein as "Selective Call Rejection," is implemented in SCP 220; the implementation of this new
service function is essentially a variation of the conventional "Anonymous/Unavailable Call Rejection" service.
According to the principles of the Selective Call Rejection service function, if the identity of the calling party telephony device received by the SCP 220 from the SSP 210 in the Termination Attempt message is equivalent to some predefined criteria, a Send To Resource message, as generally defined by AIN 0.1, incorporated herein by reference, is sent from the SCP 220 to the SSP 210. The predefined criteria can be, for example, "No ID," "Anonymous," "Unavailable," "Private," or "Blocked." The Send To Resource message instructs the SSP 210 to direct a prerecorded announcement to the calling party telephony device and to collect any received digits, or "user input data," received from the calling party telephony device.
If, prior to the end of the prerecorded announcement, user input data is received from the calling party telephony device, it is forwarded from the SSP 210 to the SCP 220 within a Resource Clear message (see AIN 0.1). Within the SCP 220, the Selective Call Rejection service function can compare the user input data to one or more "control codes" that define how the call request should proceed; i.e., the SCP 220 instructs the SSP 210 to process the call request as a function of the user input data. For example, a control code could be an identifier pre-selected by a subscriber associated with the called party device; e.g., the control code could be a Personal Identification Number (PIN), which the called party can provide to a person they desire to receive calls from, regardless of from what telephony device that person is calling. Alternatively, the Selective Call Rejection service function can direct the SSP 210 to connect any call during which user input data is received, regardless of whether that user input data is equivalent to a control code.
In one embodiment, regardless of whether the user input data is equivalent to some prestored criteria, or control codes,, the SCP 220 can instruct the SSP 210 to substitute the user input data for the calling party device identifier when connecting the call request to the called party telephony device; the called party can then decide whether to answer the call based on the received user input data. For example, if the calling party device identifier received by the SCP 220 is "Unavailable," the SCP could instruct the SSP
210 to play a prerecorded announcement that requests the calling party to input their telephone number; alternatively, if the calling party device has an alphabetic character input means associated with it, the calling party could input their name. The user input data can then be substituted for the calling party device identifier when connecting a call to the called party telephony device. The SCP 220 can also instruct the SSP 210 to use a distinctive ring that is a function of the user input data when the SSP connects the call request to the called party telephony device. The possible variations for notifying a called party of an incoming call, and providing information relating to the identity of the calling party, are essentially limitless using the general principles of the present invention; such variations are intended to be within the broad scope of the claims recited hereinafter.
If the calling party telephony device disconnects during the prerecorded announcement, the SSP 210 preferably sends a Resource Clear message within a response package to the SCP 220, with a ClearCause element indicating "Caller Abandon" (see AIN 0.1). Upon receipt of a Resource Clear (Caller Abandon) message from the SSP 210, the SCP 220 sends an Authorize Termination message to the SSP, which releases the call transaction and terminates the service logic. If no digits are received from the calling party telephony device by the end of the announcement, the SSP 210 preferably sends a Resource Clear message within a conversation package to the SCP 220, with a ClearCause element indicating "Timeout" (see AIN 0.1). Upon receipt of a Resource Clear (Timeout) message from the SSP 210, the SCP 220 sends a Disconnect message to the SSP to disconnect the ongoing call.
Finally, turning to FIGURE 3, with continuing reference to FIGURE 2, illustrated is a flowchart of an exemplary method 300 according to the principles of the present invention. In a Step 310, a device identifier is received in association with a call request from a calling party telephony device to a called party telephony device. Next, in a Step 320, it is determined whether the device identifier is equivalent to some predefined criteria, such as "No ID," "Anonymous," "Unavailable," "Private," or "Blocked." If the device identifier is not equivalent to the predefined criteria, the call request is handled
using conventional methods in Step 330; otherwise, the call request is processed according to the Selective Call Rejection service function disclosed herein.
If the device identifier is equivalent to the predefined criteria, a prerecorded announcement is played to the calling party telephony device in Step 340 and, simultaneously, user input data can be received from the calling party telephony device in Step 350. Next, in Step 360, it is determined if any user input data was received prior to the termination of the prerecorded announcement. If no user input data was received prior to the termination of the prerecorded announcement, the call is disconnected in a Step 370. If user input data was received, it can be compared to a one or more preselected identifiers, or control codes in Step 380. In Step 390, it is determined whether the user input data is equivalent to any of the preselected identifiers; if it is not, then the call is disconnected in Step 370. If the user input data is equivalent to a preselected identifier, however, the call request is routed to the called party in Step 395.
From the foregoing, those skilled in the art will recognize that the present invention advances the state of the art of communications systems, providing an advanced IN service for selectively connecting automatically-rejected telephone calls, thereby overcoming a disadvantage of IN services that automatically-reject telephone calls. Although the present invention has been described in detail, those skilled in the art will conceive of various changes, substitutions and alterations to the exemplary embodiments described herein without departing from the spirit and scope of the invention in its broadest form. In particular, although the principles of the present invention have been described as being implemented in a SS7 network, those skilled in the art will recognize that the novel functionality disclosed herein also could be implemented through other types of networks, such as an Internet Protocol (IP) network. The exemplary embodiments presented herein illustrate the principles of the invention and are not intended to be exhaustive or to limit the invention to the form disclosed; it is intended that the scope of the invention only be limited by the claims appended hereto, and their equivalents.