Patent Abstract:
A method and system for call restoration in a video relay service are disclosed, including a system that includes a VRS server having a call queue. The VRS server receives at least one call request to establish a communication session between a hearing-impaired user and a hearing-capable user. The VRS server also compares the call request with the plurality of call requests to identify if the call request corresponds to a previous call request corresponding to one in the call queue. The system also includes a VRS client application interactively coupled to the VRS server and configured to monitor availability of interpretive services. When the call request corresponding to the hearing-impaired user and the hearing-capable user is sorted to a top of the call queue and the interpretive services are available, the application establishes the communication session via the interpretive services between the hearing-impaired user and the hearing-capable user.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to call restoration in a communication system, and, more particularly, to a method and system for retaining a queuing order for interrupted calls in a communication system. 
     2. State of the Art 
     Connection-based or point-to-point calls such as traditional telephone calls, for example, over a public switched telephone network, are generally established in a real time or near real time manner. As such, the establishment of communication sessions generally does not require the formation of a queue or waiting list for the establishment of connection-based calls. 
     However, when a communication session requires, for example, an intermediary service, such as interpretive services for the deaf or hearing-impaired, the formation of a queue or waiting list is commonplace as call-initiating parties await the availability of interpretive services. Because of the latency of establishing a communication session, opportunities exist for the partial communication session between a calling party and an interpretive service to be interrupted, resulting in the loss of priority or position in the queue when the calling party reinitiates contact with the interpretive services. 
     Similarly, a channel formed between a calling party and an interpretive service provider may frequently be established over a connectionless network. Such alternative network configurations between a called party and an interpretive service may be required due to the enhanced bandwidth nature of such a connection, particularly if such a connection employs a broadband device, such as a video phone for communicating between the called party and the interpretive service. As such, a broadband network for facilitating the transfer of an enhanced bandwidth data may employ connectionless channels such as one employing Internet Protocol (IP) or other packetized connectionless technologies. It is appreciated by those of ordinary skill in the art that such connectionless based networks regularly experience dropped packets or other network interruptions that may cause the connectionless based communication link between a calling party and an interpretive service to be dropped or otherwise lost. In such an environment where a calling party assumes a position in a queue while awaiting, for example, interpretive services, the calling party would lose their position in the queue and upon subsequent reconnection would assume a more unfavorable position in the queue, namely joining the queue in the lowest priority or last position. 
     Therefore, in order to provide an enhanced experience for a user in a communication system where a calling party assumes a position in a queue while awaiting the completion of the establishment of a communication session, the need exists for recovering from the loss of a dropped connection during the establishment of a communication session or partial session utilizing a form of intermediary services. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to a method and system for call restoration in a video relay service. In one embodiment of the present invention, a system is provided for a video relay service (VRS) system. The system includes a VRS server, including a call queue. The VRS server is configured to receive at least one call request to establish a communication session between a hearing-impaired user and a hearing-capable user and maintain the call queue. The call queue includes a plurality of call requests with each call request including call information regarding the hearing-impaired user and the hearing-capable user. The VRS server also includes control logic configured to compare the call request with the plurality of call requests and to identify if the call request corresponds to a previous call request corresponding to one in the call queue. The system also includes a VRS client application interactively coupled to the VRS server and is configured to monitor availability of interpretive services; when the call request corresponding to the hearing-impaired user and the hearing-capable user is sorted to a top of the call queue and the interpretive services are available, the application establishes the communication session via the interpretive services between the hearing-impaired user and the hearing-capable user. 
     In another embodiment of the present invention, a method is provided for electronic communication with a hearing-impaired user. At least one call is received including a call request, which further includes call information regarding the hearing-impaired user and the hearing-capable user. A call queue is maintained, which comprises a plurality of call requests corresponding to a plurality of calls. The call requests each include a call record comprising a call status of a corresponding call. The call is restored according to the call status in the call queue when the call information of the at least one call matches the call record of one of the plurality of call requests in the call queue. 
     In another embodiment of the present invention, a method is provided for restoring an interrupted communication session between a hearing-impaired user and a hearing-capable user. A call request is received that includes call information relating to the hearing-impaired user and the hearing-capable user. The call information of the call request is compared with a plurality of call information corresponding to a plurality of call requests in the call queue. When one of the plurality of call information of one of the plurality of call requests in the call queue corresponds to the call information of the call request, the communication session is reestablished according to the call information between the hearing-impaired user and the hearing-capable user. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       In the drawings, which illustrate what is currently considered to be the best mode for carrying out the invention: 
         FIG. 1  illustrates a hearing-impaired communication system, in accordance with an embodiment of the present invention; 
         FIG. 2  illustrates a simplified block diagram of a hearing-impaired communication system, in accordance with an embodiment of the present invention; 
         FIG. 3  is a functional block diagram of a video relay service configured for operation with a hearing-impaired communication system; 
         FIG. 4  is a flow diagram of call restoration within a video relay service, in accordance with an embodiment of the present invention; and 
         FIG. 5  is a flow diagram of processing a call request, in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  illustrates a hearing-impaired communication system configured to facilitate a communication session between a hearing-impaired user and a hearing-capable user, in accordance with an embodiment of the present invention. A hearing-impaired communication system  10  enables a hearing-impaired user  14  to engage in conversation through a communication system with a hearing-capable user  16 . A communication session between the users is facilitated through the use of various equipments, which are preferably coupled together using various networks including a telephone network, such as the Public Switch Telephone Network (PSTN). 
     To interface a hearing-impaired user into a generally voice-based communication system, interpretive services are employed allowing hearing-impaired users to communicate with an interpreter, namely through sign language. The sign language images are then translated by a video relay service  20  and when translated into voice information, are then forwarded over a voice-based communication connection to a hearing-capable user. One means for relaying the communicative expressions of a hearing-impaired user  14  within hearing-impaired communication system  10  incorporates a video phone  12  for capturing and displaying the communicative expressions exhibited by hearing-impaired user  14  and for displaying interpreted voice information originating from the hearing-capable user. The expressions, such as sign language and/or body language, may be interpreted or translated by video relay service  20 . Hearing-capable user  16  interacts in a conventional manner with video relay service  20  through the use of a voice-based dialogue conveyed over a conventional voice phone  22 . The various devices, such as video phone  12  and conventional voice phone  22  are coupled to video relay service  20  using one or more networks  17 ,  18 . To facilitate the enhanced bandwidth needs of video phone  12 , network  17  may be implemented as a high bandwidth network such as a DSL, Cable, Ethernet or other enhanced-bandwidth networking technology. Network  18  may be implemented according to the standards and bandwidth requirements of conventional voice phone  22 . 
       FIG. 2  is a simplified diagram of a hearing-impaired communication, system  10 , in accordance with an embodiment of the present invention. To facilitate the interaction with a hearing-impaired user, a video phone  12  includes video components such as a camera  24  for capturing the communicative expression of a hearing-impaired user and further includes a display or monitor  26  for displaying the communicative expressions originating from the hearing-capable user as interpreted by video relay service  20 . 
     Video phone  12 , in accordance with an embodiment of the present invention, further includes a keypad  28  or other data entry device configured to enable a hearing-impaired user to initiate a communication session in a conventional manner by entering the telephone number of the hearing-capable user, also known herein as a called party telephone number, which is captured and stored as captured called party number  32 . In accordance with one embodiment of the present invention, the hearing-impaired user is able to interact with video phone  12  to initiate a phone call in a manner consistent with the interaction of a hearing-capable user initiating a phone call using a conventional telephone. Specifically, a hearing-impaired user enters, using an input device such as keypad  28 , the called party number that is captured by a control process  30  and stored as a captured called party number  32 . 
     Control process  30  retrieves a stored VRS number  34 , which identifies a specific video relay service, and using a protocol, such as DNS or LDAP protocol, contacts a DNS or an LDAP server  200  and passes thereto a domain name or stored VRS number  34  and requests therefrom a corresponding IP address  202 , which is returned to video phone  12 . Video phone  12  thereafter initiates a call to video relay service  20  over network  17  using, for example, corresponding IP address  202  as returned from LDAP server  200 . Control process  30  initiates a communication session over network  17  between video phone  12  and video relay service  20 . In one embodiment of the present invention, the communication session between video phone  12  and video relay service  20  is more specifically initially connected to a hold server  44  within video relay service  20 . Hold server  44  communicates with a VRS server  45  and when hold server  44  receives an inbound call in the form of a call request for the establishment of a communication session between video phone  12  and video relay service  20 , hold server  44  notifies VRS server  45  of the intention to establish a communication session between video phone  12  and conventional voice phone  22 . During the establishment of the communication session between video phone  12  and video relay service  20 , video phone  12  passes a call request including calling information to hold server  44 . The call request is subsequently passed to VRS server  45  including the calling information, which includes a video phone number  204 , a MAC address  206 , a name  208  and captured called party number  32 . VRS server  45  includes and maintains a queue for one or more calls originating from video phones  12  seeking to establish or maintaining a communication session utilizing interpretive services as provided within VRS client  36 . 
       FIG. 3  is a functional block diagram of a hearing-impaired communication system  10  including a video relay system, configured in accordance with an embodiment of the present invention. The video phone  12  and voice phone  22  interact via video relay services  20  and as further coupled via network  17 ,  18 . Video relay services  20 , in addition to providing interconnection and interpretive services between a hearing-impaired user and a hearing-capable user, further provides reestablishment of a dropped or otherwise interrupted session, in accordance with an embodiment of the present invention. During the establishment of a connection between a video phone  12  and video relay services  20 , call information including video phone number  204 , MAC address  206 , and captured called party number  32  are forwarded according to control logic  47  via hold server  44  to VRS server  45 . 
     Additionally, when a connection with video phone  12  is received at hold server  44 , hold server  44  begins timing the duration of the call on hold at hold server  44  prior to passing the call request and forwards to VRS server  45  a duration time on hold  210  before VRS server  45  is notified for use in prioritizing calls within call queue  220 . When a call is received at VRS server  45 , the call queue  220  is reprioritized or resorted, in accordance with the received call information. 
     Each call within call queue  220  is assigned a call record ID  222  that contains information regarding the specifics of the call for use in prioritizing or reattaching a call to a queue position and reestablishing a dropped or otherwise unintentionally terminated communication session. Call record ID  222  includes a call center ID  224 , which may specify a specific one of a plurality of call centers providing interpretive services for servicing video relay service  20 . Such identification enables the reestablishment of an unintentionally interrupted communication session. 
     Call record ID  222  further includes a deaf ID  226  and hearing ID  228  that provide an identification of the respective deaf and hearing users. Call record ID  222  further includes a call initiating ID  230  identifying which of the parties, the hearing-impaired or the hearing-capable party, initiated the call. Additionally, a reestablished time out  232  identifies a settable time out period within which an unintentionally terminated call may be reestablished without discarding such a call as an abandoned call. A call start time stamp  234  identifies the beginning time of an established session while a scheduled call time  236  identifies the requested start time for a previously scheduled call within video relay service  20 . Call record ID  222  further includes a hearing phone number  238  and a deaf phone IP address  240  identifying the respective originating and destination devices. 
     A call priority  242  identifies emergency or otherwise higher priority devices. Call record ID  222  further includes a call termination type  244  identifying the termination status of a call, which may specify a requested normal type termination, or may be used for other testing or no answer type terminations. Call termination type  244  may be input and changed by an interpreter performing the interpretive services thereby identifying when a call terminates correctly or when an interruption occurs. A call state  246  identifies an ongoing status of a particular call including awaiting interpretive services state, call in process state and call terminated state. Call record ID  222  further includes an interpreter ID  248  utilized to store an identifier designating a specific interpreter performing interpretive services between the hearing-impaired user and the hearing-capable user. While call record ID as described herein includes various data elements, a subset or further augmentation of call record ID  222  is contemplated within the scope of the present invention. 
     Video relay service  20  further includes a VRS client  36 , which provides interfaces to both the hearing-capable user at a voice phone  22  via network  18 , and an interface with an interpreter  48  through interpreter services  40 , which further includes video and voice interfaces  50 ,  52 . The VRS client  36  notifies the VRS server  45  via control  37  when interpretive services are available. VRS server  45  thereafter services the next call request in the call queue  220 . VRS client  36  then receives the call from the hold server  44  when the VRS server  45  determines which call request in the call queue  220  has priority and then instructs the hold server  44  to transfer the call to the VRS client  36 . 
       FIG. 4  is a flow diagram illustrating the establishment of a communication session and recovery following a call interruption  390 , in accordance with an embodiment of the present invention. In the present embodiment, a video phone  12  initiates a call  300  to video relay services  20  and passes thereto various call information, including video phone number  204 , MAC address  206 , a name  208  and captured called party number  32 . A hold server  44  of video relay services  20  receives the initiated call and places the call on hold and issues a service&#39;s request to enter request  310  the call into a queue within VRS server  45 . Information passed during enter request  310  includes video phone number  204 , MAC address  206 , a name  208 , called captured called party number  32  as well as a duration time on hold  210  for delay encountered by the call while waiting on hold server  44 . 
     VRS server  45  compares  320  the received information with any other entries within the call queue  220  ( FIG. 3 ). If an entry within the call queue  220  corresponds to the received call information, an interrupted session or scheduled call is detected and, depending upon the call state, the call is either reestablished  330  if the communication session between the users was in progress or in the event that a connection was terminated while the user remained in the queue, then the user re-attaches  330  to the queue position previously held. 
     If a match corresponding to the received call information is not detected within the queue, then the new call request causes a call record ID  222  ( FIG. 3 ) to be opened and populated according to the received call informations. The call is then entered  340  into the queue and the queue is resorted based upon all entries within the queue. The call remains on hold at the hold server  44  with the VRS server  45  maintaining the call queue  220  and updating the hold times and other respective a information within call record ID  222  ( FIG. 3 ). 
     When interpretive resources become available  345 , VRS server  45  issues a transfer request  350  designating a specific VRS client ID to which the hold server  44  should route the call corresponding to the call record ID on the top of call queue  220  ( FIG. 3 ). Hold server  44  transfers  360  the call to VRS client  36  and VRS client  36  correspondingly completes  370  the connection with voice phone  22 . During the established session, the call records are updated  380  to maintain information within call record ID  222  ( FIG. 3 ) useful in the event of a call interruption  390 . 
     If a call session is in progress and is subjected to a call interruption  390 , processing reverts back to call initiation followed by subsequent detection of an interrupted session and the reestablishment of the call. When call interruption  390  is not present, VRS client  36  closes  400  connection with voice phone  22  and updates  410  the call record ID  222  ( FIG. 3 ) to specify a proper termination or a termination type within the call record and then the connection is closed  420  with video phone  12 . 
       FIG. 5  is a flow diagram of comparison procedures for determining whether a received call was either in queue at the call queue or in progress during a session, in accordance with an embodiment of the present invention. When a call  300  is received and placed on holds ( FIG. 4 ) at hold server  44  ( FIG. 4 ), hold server  44  issues a call request  310  ( FIG. 4 ) for the newly received call to enter the queue of VRS server  45  ( FIG. 4 ). Once the call request is received at VRS server  45 , the received information is compared  320  against each existing queue entry. In a matching or comparison process  322 , when a match corresponding to the received information is not detected, the call is entered  340  into a call queue  220  ( FIG. 3 ) with the entries within the call queue  220  being resorted according to criteria such as call priority (e.g., emergency calls) and cumulative hold times for each respective call. 
     When a match is detected, the call state is determined  332  in an attempt to evaluate whether the call was on hold within the call queue or whether the call was previously active prior to the call interruption. When the call state as determined within the corresponding call record ID  222  ( FIG. 3 ) lists the call as being previously in the queue position, then the new call is re-attached  336  to the previously held queue position. When it is determined from the call state that the call was in progress or in session, the VRS server  45  ( FIG. 4 ) requests  334  that the hold server reestablish the call with the retrieved VRS client as stored within the corresponding call record. 
     While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.

Technology Classification (CPC): 7