Abstract:
A communications system is designed to allow sound-impaired persons to communicate with sound-unimpaired individuals via the Internet. When a sound-impaired person at a Text Teletypewriter (TTY) terminal initiates a call that is destined for a sound-unimpaired person, the communications system ascertains whether the sound unimpaired person is currently using the Internet and, if so, automatically completes the call over the Internet and the communications system without the help of any communications assistant.

Description:
FIELD 
     This invention relates to a method and apparatus to help Internet users communicate with hearing and speech-impaired individuals while such individuals are using a Baudot-based device. 
     BACKGROUND 
     In an effort to make the benefits of communications technology available to everyone, regardless of any disability that a particular person may have, most communications carriers offer a service called “Telecommunications Relay Service” TRS for short. In essence, the service allows sound-impaired persons, i.e., hearing- and/or speech-impaired individuals, to communicate with each other as well as with sound-unimpaired persons using special user-based devices and customized network-based facilities. User-based devices typically used by sound-impaired persons are Telecommunications Devices for the Deaf (TDD), better known as Text Teletypewriters (TTY). Such a device is a specialized terminal with a keyboard on which text characters are typed for conversion to tones using well-known Baudot-format. A TTY device is generally coupled to a communications line that carries the tones across a communications network to a corresponding TTY where the tones are re-converted to characters that are displayed on the screen of the corresponding TTY device. Force of habit and governmental subsidies that help defray the cost of each TTY device have made such device the preferred communications device of the majority of sound-impaired persons. 
     The customized network-based facilities that serve sound-impaired individuals are either Operator Services for the Deaf (OSD) or Telecommunications Relay Service (TRS). The OSD facility relays text communications back and forth between TTYs being used by two sound-impaired individuals. The TRS facility permits conversation between a sound-unimpaired individual and a sound-impaired person. Such conversation is generally facilitated by a communications assistant who types the speech signals received from the sound-unimpaired individual for delivery to the TTY of the sound-impaired individual, and correspondingly reads the text data that is received from the sound-impaired individual, for delivery to the telephone set of the sound-unimpaired individual. 
     The active participation of the communications assistant in a conversation between a sound-impaired user and a sound-unimpaired person, although beneficial, is nevertheless expensive and intrusive. The relatively high cost associated with the participation of a communications assistant in the conversation is due to the fact that an assistant must be dedicated to each conversation. Although the cost of providing TRS facility is typically governmentally subsidized, sound-impaired individuals fully realize that, absent the current governmental generosity, the mere existence of universal communications service for the sound-impaired may be in jeopardy. 
     In response to this problem, some network designers have proposed the concept of implementing Speech-To-Text (STT) and Text-To-Speech (TTS) conversion technology at the TRS platform. Unfortunately, while TTS technology has been successfully implemented in a wide variety of applications, STT technology is still in its infancy due to a variety of technical issues, including problems related to vocabulary independence and speech recognition for signals transmitted via communications lines. Furthermore, sound-impaired individuals tend to use some idiomatic expressions that are not easily recognizable by the general public and that are not easily adaptable to existing SST systems. 
     Sound-impaired users have long complained about the lack of privacy in their conversation with sound-unimpaired persons due to the active participation of the communications assistant who is in effect a non-invited, albeit needed, eavesdropper to a private conversation. Thus, a problem of the prior art is lack of an intruder-free, affordable, universally available system to provide communications services to sound-impaired individuals 
     SUMMARY 
     We have realized that while the vast majority of sound-impaired individuals use TTY devices for their telecommunications needs, a significant number of sound-unimpaired communications users who place calls to sound-impaired individuals are Internet users. 
     The present disclosure is directed to a communications system that allows Baudot-formatted text data from TTY devices to be carried over the Internet after such text data has been converted to the Transmission Control Protocol/Internet Protocol (TCP/IP) required for communications over the Internet. Analogously, TCP/IP packets that originate from a sound-unimpaired Personal Computer (PC) and that are destined for the TTY of a sound-impaired person are received at a server on the Internet where such packets are converted to Baudot-formatted text data for delivery to the TTY of the sound-impaired person. 
     In an embodiment of the principles disclosed herein, a sound-impaired person wishing to communicate with a sound-unimpaired person directs a call and associated call setup information to a TRS platform. The call setup information includes the telephone number of the desired called party, i.e., the sound-unimpaired person. Upon receiving the call setup information, the TRS platform launches a query to a database that maps the called party&#39;s telephone number to the IP address of the called party. Upon retrieving the IP address of the IPS server, the TRS platform instructs its protocol conversion server to access a commercially available web site to ascertain whether the called party is presently using the Internet. If so, the called party is alerted to the presence of the call from the sound-impaired person. Upon receiving a signal indicative of the willingness of the called party to answer the call via the Internet network, the TRS platform establishes a two-leg virtual connection between the called party&#39;s PC and the TTY of the caller, i.e., the sound-impaired person. The first leg of the connection—a circuit-switched connection—couples the caller&#39;s TTY to the protocol conversion server while the second leg of the connection—a packet-switched connection—couples the protocol conversion server to the called party&#39;s PC. After the two-leg connection is established, the TRS platform separates itself from the connection. 
     If the called party is not currently using the Internet, the TRS platform places a conventional call to the called party urging such party to establish an immediate Internet connection to the protocol conversion server. When such connection is established, the TRS platform bridges the caller&#39;s TTY to that connection and drops out of the loop. 
     When a sound-unimpaired caller wishes to communicate with a sound-impaired called party, the caller can either place a conventional TDD call or an Internet-TDD call. If the call is a conventional TDD call, the call is completed to the TRS platform, which delivers an announcement to the caller to inform such caller that an Internet call to the TTY user would afford the caller more privacy at a cheaper rate. The announcement also communicates to the caller the Universal Resource Locator (URL) of the Internet-TDD website on the protocol conversion server. Thereafter, the TRS platform completes the call in a conventional manner. If the call is an Internet call, an Internet connection is established from the caller&#39;s PC to the protocol conversion server. Once the connection is established, IP data packets received from the caller are converted to Baudot format characters at the protocol conversion server before being forwarded to the called party&#39;s TTY. Correspondingly, Baudot-format characters received from the called party&#39;s TTY are packetized in conformance with the IP protocol before being forwarded to the Internet caller. 
     Advantageously, the present disclosure eliminates the need for sound-unimpaired persons who communicate frequently with sound-impaired individuals to purchase a TTY whose use is dedicated to such communications. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a simplified functional block diagram of a communication system using an internet capable device, such as a personal computer, to communicate with a TTY device over the internet; and 
     FIGS. 2,  3  and  4  illustrate programmed instructions executed by different components of FIG. 1 to implement the principles disclosed herein. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 is a simplified functional block diagram of a communications network that is arranged to implement the principles disclosed herein. Shown in FIG. 1 is a TTY  101 , which is coupled to a communications carrier network  103  via a twisted pair loop  130 . Communications carrier network  103  includes a TRS platform  104 , a database  109  and a protocol conversion server  113 . The TRS platform  104  includes a PBX  105 , communications assistant position  108 , a processor  107  and a Voice Response Unit (VRU)  106 . PBX  105  is a premises-based voice switching system which includes a modem pool (not shown) to which are directed all TDD calls. PBX  105  serves as the switching center or traffic cop for TDD calls. PBX  105  is equipped with an automatic call director facility arranged to facilitate the transfer of calls from one incoming channel of a trunk group ( 133  to  136 ) to an outgoing channel of another trunk group ( 133  to  135 ). PBX  105  switches incoming calls from TTY  101  to processor  107  for further processing. Correspondingly, calls from a conventional telephone set, such as set  122  that are destined for TTY  101  are directed to VRU  106  for delivery of announcements or to CA position  108  for live attendant assistance. Persons skilled in the art would readily recognize that the functions performed by PBX  105  could be adequately and cost-effectively performed by a central office switch with call director functionality. 
     VRU  106  is a processor-controlled voice information system that is driven by system software comprised of commands to i) answer incoming calls, ii) direct callers to enter specific information to process their calls, iii) initiate calls, and iv) transfer calls to other components of TRS platform  104 . VRU  106  may be implemented using the Lucent Technologies Conversant® Voice Information System whose architecture and features are described in  AT&amp;T Technical Journal , Vol. 65, Issue 5, pp. 34-47, Sep/Oct. 1986. 
     Communications carrier network  103  also includes database  109  and protocol conversion server  113 . Database  109  is a processor-controlled database management system that maps subscribers&#39; telephone numbers to their names and/or IP addresses. Although database  109  is shown located within communications carrier  103 , it is to be understood that database  109  may also be a server within Internet network  120  that may be accessed via a website with a known Universal Resource Locator (URL). Protocol conversion server  113  is a conventional computer that serves as a gateway between the Internet network  120  and the communication carrier network  103 . Protocol conversion server  113  also executes software instructions designed to convert Baudot-formatted data to ASCII-formatted data when TTY  101  can only send and transmit Baudot-formatted data. Other functions performed by protocol conversion server  113  include forming IP packets for ASCII-formatted data destined for Internet network  120  and de-packetizing IP data packets received from Internet network  120  prior to converting such data to Baudot format. It is also worth noting that some TTYs use improved Baudot formats, such as the so-called “Turbocode®” used by TTYs from Ultratec Corporation. The protocol conversion functions performed by server  113  also extend to the enhanced Baudot formats. 
     FIG. 1 also shows Internet network  120  to which is coupled a workstation  102 . Those skilled in the art know that the Internet is actually a network of interconnected processors through which data is exchanged between such processors and other networking devices such as routers, using the well-known TCP/IP protocol. The Internet has several access points through which data can be sent and received. For the sake of simplicity, a single access/egress point is shown as Internet Service Provider (ISP) processor  121 . The processors of the Internet are linked in such fashion that data packets that are addressed to a particular IP address are routed through one or more hops by these processors and routers and delivered to the proper address. 
     As shown in FIG. 2, the process contemplated by this disclosure is initiated in step  201  when a sound-impaired person at TTY  101  initiates a TDD call that is destined for telephone set  122 . The TDD call is established according to a two-phase process. In a first phase, as indicated in step  202 , a first connection is established to TRS platform  104  or more specifically to PBX  105 . Upon determining that the call is a TDD call, PBX  105  transfers the call to processor  107  which invites the sound-impaired caller to type the telephone number and optionally the name of the called party. Upon receiving the called party number, processor  107  in step  203 , launches a query to database  109  to retrieve the IP address of the called party. The aforementioned database search-can be accomplished in many ways, including accessing an Internet website to find the IP address associated with the telephone number and/or name provided by the TDD caller. If no IP address can be found for the called party, as determined in step  204 , the call is transferred to CA position  108  for the call to be completed in a conventional manner, as indicated in step  205 . In a departure from the prior art, the communications assistant may inform the called party that calls to and from a sound-impaired person can be completed with complete privacy and at cheaper rates by accessing a particular website at protocol conversion server  113 . Alternatively, VRU  106  may deliver an announcement to the called party giving such called party the choice of either using the conventional services of the communications assistant, or accessing the web site at protocol conversion server  113  to communicate with the TDD caller. The announcement would include the Universal Resource Locator (URL) of the Internet-TDD website on the protocol conversion server  113 . If the called party elects to communicate with the TDD caller via the Internet, VRU  106  would transfer the call to protocol conversion server  113  for further processing. 
     If an IP address is found for the called party, processor  107 , in step  206  further determines whether the called party is currently using the Internet. If the user is currently using the Internet, as determined in step  206 , processor  107  in step  207  alerts the called party of the call in waiting. The aforementioned alert may take the form of an electronic mail message that is sent to the called party. The electronic message may indicate to the called party that a TDD call destined for him or her is waiting to be completed and conversation can start as soon as he or she joins the caller in a chat room or private room at a particular Universal Resource Locator (URL) associated with protocol conversion server  113 . 
     When processor  107  receives a signal indicative of the called party&#39;s willingness to answer the TDD call, as determined in step  208 , processor  107  in step  209  establishes an Internet connection from the called party&#39;s Personal Computer (PC) through the protocol conversion server  113  to TTY  101 . Immediately thereafter, processor  107  in step  210  drops out of the connection. Once the Internet connection is established protocol conversion server  113  in step  211  notifies the calling and called parties that they can start their private conversation. 
     If processor  107  receives no signal indicative of the called party&#39;s willingness to answer the TDD call, as determined in step  208 , then processor  107  in step  205  transfers the call to CA position  108  for the call to be answered in a conventional manner. Similarly, if the called party is an Internet subscriber but is not currently using the Internet, as determined in step  206 , processor  107  in step  205 , transfers the call to attendant position  108  for the call to be answered in a conventional manner. The CA handling the call may, in step  212 , advertise the Internet-TDD service to the called party before the conversation between the two parties begins. 
     The manner in which a TDD call is carried over the Internet is described in FIG.  3 . Once an Internet virtual communications path is established between the calling and called parties (TTY  101  and workstation  102 , respectively), the protocol conversion server  113  and the Internet Service Provider (ISP) server  121 , the protocol conversion server  113 , in step  301  waits for data to be received therein. When Baudot-formatted data from TTY  101  is received at the protocol conversion server  113 , as determined in step  302 , such data is converted by the protocol conversion server  113  into ASCII format in step  303 , before protocol conversion server  113  forms IP packets with the ASCII-formatted data. Thereafter, protocol conversion server  113 , in step  304 , transmits the IP packets to workstation  102  via ISP server  121  and communications line  132 . Those skilled in the art would readily recognize that when the data received from TTY  101  is already in ASCII format (since some newer model TTY devices send and receive ASCII characters as opposed to Baudot tones), no protocol conversion function needs to be performed by server  113 . 
     When IP packets are received from workstation  102  by protocol conversion server  113 , as determined in step  305 , protocol conversion server  113 , in step  306 , de-packetizes such IP packets and converts the ASCII data contained in those packets into Baudot-formatted data. Thereafter, protocol conversion server  113 , in step  307 , transmits the Baudot-formatted data to TTY  101 . No protocol conversion function is performed when TTY  101  can process ASCII-formatted data. 
     FIG. 4 illustrates a process by which an Internet caller can complete a TDD call. The process is initiated in step  401  when an Internet caller establishes a connection to ISP server  121  to access a web site at protocol conversion server  113 . The process of establishing a connection to a web site may require a caller to provide a password or Personal Identification Number (PIN) for billing and/or security purposes. Once the web site is accessed, the caller is prompted in step  402  to provide the telephone number of the sound-impaired called party. Once the protocol conversion server  113  receives the called party number in step  403 , protocol conversion server  113  establishes a serial port connection to TTY  101 , as indicated in step  404 . Upon receiving a signal from TTY  101  indicative of the called party&#39;s willingness to answer the call as determined in step  405 , protocol conversion server  113 , in step  406 , notifies TTY  101  and workstation  102  that data can be freely and privately exchanged between these two devices. If no signal indicative of the called party&#39;s willingness to answer the call is received by protocol conversion server  113 , as determined in step  405 , protocol conversion server  113  sends a standardized message to the caller to inform the caller that the called party is unavailable. Optionally, protocol conversion server  113  may invite the caller to type a message for the called party for delivery at a later time. 
     The foregoing merely illustrates certain aspects of the principles disclosed herein. Persons skilled in the art will be able to devise numerous arrangements which, although not explicitly shown or described herein, embody the principles disclosed herein, and are within the spirit and scope of the present disclosure.