Abstract:
A method and apparatus for accepting an incoming message over a packet network and transmitting it over a circuit switched network using a highly scalable architecture. The architecture utilizes a message queue and a router/filter within a private data network which is connected to an external data network such as the Internet, with separate outbound resource servers to provide the high degree of scalability, for handling a variety of message types.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to the field of message receipt/transmission and delivery using computer, phone, wireless and other communications networks. Specifically, the present invention relates to the transmission of e-mail messages which may be text only, text plus an audio file, text plus a video file, text plus a fax file or any combination thereof to a phone, pager or fax machine or other receiving device suitable for the message content, over appropriate communications networks using an architecture which enables easy expansion to handle additional message traffic as well as to connect to additional communications networks, including networks which do not presently exist which may become available in the future.  
           [0003]    2. Description of Related Art  
           [0004]    Voice and data communications systems such as the public switched telephone network (PSTN) are currently used to transfer image and text data transmitted by facsimile (“fax”) machines in addition to the normally carried voice traffic. These faxed images are usually transmitted through the PSTN and received for printout or storage of the image on a destination fax machine or computer for the use by the recipient.  
           [0005]    In U.S. application Ser. No. 08/829,857 filed Apr. 1, 1997 entitled Method and Apparatus for Transmission and Retrieval of Facsimile and Audio Messages Over a Circuit or Packet Switched Network, it is disclosed that to provide for the receipt and transmission of audio and fax information by a first user over a circuit switched network such as the public switched telephone network (PSTN) to a second user over a packet switched network such as the Internet, a communications server is connected both to the circuit switched network and a packet switched network.  
           [0006]    The communications server contains resources to receive and process incoming audio and facsimile calls from the circuit switched network into a format suitable for transmission over the packet switched network to the second user&#39;s address. In addition, a link is first determined between the second user&#39;s address on the circuit switched network and the second user&#39;s address on the packet switched network, and then an appropriate route to the second user&#39;s address on the packet network is determined. With the system being maintained in a distributed and redundant fashion, reliable receipt and transfer of all messages is ensured. A copy of the specification and drawings of U.S. application Ser. No. 08/829,857 is attached hereto as Appendix I.  
           [0007]    However, the architecture utilized as described in U.S. application Ser. No. 08/829,857 is not easily scalable to handle increasingly higher levels of message traffic or to easily connect to networks in addition to the PSTN and the Internet. FIG. 1 shows the essence of the architecture of U.S. application Ser. No. 08/829,857. An e-mail message is passed to an outbound resource 11 (communications server  150  in U.S. Application Ser. No. 08/829,857) which converts the e-mail message to a fax format or to audio for transmission to a fax machine or telephone connected to the PSTN. A database  13  stores customer information necessary for processing of messages (an unnumbered part of communications server  150  in U.S. application Ser. No. 08/829,857 which is also contained in database server  195  in U.S. application Ser. No. 08/829,857). After processing of an e-mail message by outbound resource  11 , a fax or voice mail message is sent over the PSTN or more generally, a generalized switched telephone network (GSTN) which includes cellular telephone networks as well as the PSTN. Optionally, a pager message may also be sent informing a user of the fax which has been sent or availability of a voice mail message as described in U.S. patent application Ser. No. 08/902,400 filed Jul. 29, 1997 entitled Processing and Forwarding Messages From a Computer Network to a Forwarding Service.  
         SUMMARY OF THE INVENTION  
         [0008]    A method and apparatus for accepting an incoming message over a packet network and transmitting it over a circuit switched network using a highly scalable architecture. The architecture utilizes a message queue and a router/filter within a private data network which is connected to an external data network such as the Internet, with separate outbound resource servers to provide the high degree of scalability, for handling a variety of message types.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a block diagram of a prior art architecture which performs the functions, but not the scalability of the architecture of the present invention.  
         [0010]    [0010]FIG. 2 is a block diagram illustrating the architecture of the present invention.  
         [0011]    [0011]FIG. 3 is a block diagram showing the data/control flow through message queue  21 , router/filter  23  and database  27 .  
         [0012]    [0012]FIG. 4 ( 4   a  and  4   b ) is a flow diagram of the processing performed by router/filter  23 .  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]    The present invention provides a method and apparatus for allowing the receipt and transmission of audio, video and fax information between a circuit switched network and a packet switched network. For purposes of explanation, specific embodiments are set forth to provide a thorough understanding of the present invention. However, it will be understood by one skilled in the art, that the invention may be practiced without these details. Further, although the present invention is described through the use of circuit switched and packet switched networks, most, if not all, aspects of the invention apply to all networks in general. Moreover, well-known elements, devices, process steps and the like are not set forth in detail in order to avoid obscuring the present invention.  
         [0014]    Referring now to FIG. 2, e-mail messages for a customer are sent to/through an external data network  15  (e.g., the Internet) and routed to an appropriate SMTP/HTTP (or SHTTP) server  17  as determined by a domain name server (DNS)  18  according to well known techniques. The e-mail message may be a text message or it may include a file, the content of which may be audio, video or bitmapped (e.g., a fax) or other data. Again, the techniques for creating and sending e-mail messages with these characteristics are well known.  
         [0015]    A processing server  19 , which includes a message queue  21  and a router/filter  23  first verifies that the message is from or is to a customer using information in database  27 . After successful verification, the message is broken into fragments (in the case of files with multiple attachments) and written to message queue  21 . Router/filter  23  obtains messages from the message queue and handles least call routing/billing/ prioritization/filtering of messages. Filtering is primarily for notification messages for pager delivery. After billing verification and determination of a least cost route, the message is assigned to one or more outbound resources  31  for delivery to the intended recipient by a method or methods selected by the customer as previously recorded in database  27 .  
         [0016]    In the case of faxes, the outbound resource is a server which dials the destination fax number and sends the fax.  
         [0017]    In the case of voice messages, the outbound resource is a server which dials the destination telephone number and plays the voice message.  
         [0018]    In the case of notification messages, the outbound resource is a server which dials out to the paging terminal or delivers the notification message through any appropriate paging gateway.  
         [0019]    After the message (in whatever form) has been delivered, a receipt with details and an error log (if any) is sent back via a secure protocol to the message queue  21 .  
         [0020]    The receipt/error log messages are then processed by the router/filter which interfaces with a billing system (not shown) for customer account update.  
         [0021]    [0021]FIG. 3 is a block diagram showing the data/control flow through message queue  21 , router/filter  23  and database  27  using information contained in the following tables as explained with reference to FIGS. 4 a  and  4   b .  
                         TABLE 1                       Message Queue Table                                MESSAGE_ID   This is a unique number assigned to each message that           arrives in the system.       RESOURCE_ID   Unique number assigned to each Outbound Resource       RESOURCE_TYPE   Each Resource is identified by the type of messages it can           deliver (e.g., FAX, VOICE, NOTIFY, etc.)       RESOURCE_ADDRESS   Location of the Resource (such as IP address)       MESSAGE_TO_EMAIL_ADDRESS   To: address of the message       MESSAGE_FROM_EMAIL_ADDRESS   From: address of the message       MESSAGE_LOCATION   Location of actual message on the Message Queue 21       MESSAGE_SIZE   Size of the message in bytes       MESSAGE_PRIORITY   Priority of the message (e.g., low, medium, high)       MESSAGE_CREATION_DATE   Timestamp identifying the date/time that the message was           received by the system       MESSAGE_EXPIRY_DURATION   Amount of time after which the message becomes stale       MESSAGE_SCHEDULED_DATE   Scheduled delivery timestamp for the message       MESSAGE_STATUS   Current status of the message (Active, Pending, Sent, etc.)       MESSAGE_ESTIMATED_COST   Estimated cost for the delivery of the message       CUSTOMER_KEY   Unique number identifying the customer in the database       MESSAGE_PART_OF_BROADCAST   Flag identifying if the message is part of a larger broadcast           list waiting to be delivered       BROADCAST_ID   Unique number identifying a broadcast list       COVERPAGE_ID   Unique number identifying a coverpage (if any) for a fax       MESSAGE_SUBJECT   Subject line of the message to be delivered       MESSAGE_DURATION   Duration of the message (delivery time of fax, or delivery           time for a voice message, etc.)       MESSAGE_RATE   Rate for message delivery (dollars per second, etc.)       MESSAGE_SEND_DATE   Actual timestamp identifying when the message was           delivered       MESSAGE_REMOTE_CSID   Identifier of the fax machine to which a FAX message was           delivered       MESSAGE_TYPE   Type of message (e.g., FAX, VOICE, NOTIFICATION,           etc.)       RESOURCE_COMMUNICATION_TYPE   Protocol used to communicate with the resource (HTTP,           SHTTP, etc.)       MESSAGE_LANGUAGE_CODE   Language used for delivery of a receipt or response, based           on settings in the customer table       MESSAGE_PAGES   Number of pages of a message (used primarily for a fax)                  
 
         [0022]    [0022]                         TABLE 2                       File Type Table                                FILETYPE_MESSAGE_TYPE   Identifier of a message type (FAX, VOICE, etc.)       FILETYPE_RESOURCE_TYPE   Identifier to determine a resource that can handle a           particular file type       FILETYPE_EXTENSION   The filename extension that identifies a file type (e.g.,           WAV, TIF, JFX, AU, GSM, etc.)                    
         [0023]    [0023]                         TABLE 3                       Customer Table                                CUSTOMER_KEY   Unique number identifying a customer in the           database       FIRSTNAME   First name of customer       LASTNAME   Last name of customer       COMPANY   Company name of customer       ADDRESSLINE1   Company address       ADDRESSLINE2   Company address       CITY   Company city       MAILREGION   Company state or equivalent       MAILCODE   Zipcode or equivalent       COUNTRY   Company country       WORKNUMBER   Customer work phone number       HOMENUMBER   Customer home phone number       EMAILADDRESS   Email address of customer       COLLECTIONMETHOD   Collection method such as Credit card,           Debit, etc.       BILLTYPE   e.g., Customer, Demo, free, corporate, etc.       STATUS   Status of customer, Active, Inactive, etc.       LANGUAGECODE   Language of customer, English, German, etc.       CURRENCYCODE   Currency for billing the customer,           US Dollars, Pound Sterling, etc.                    
         [0024]    [0024]                             TABLE 4                       Currency Table                                    FORMAT   Currency label           CURRENCY_SYMBOL   Symbol for currency                        
         [0025]    [0025]                         TABLE 5                       Notification Table                                CUSTOMERKEY   Unique number identifying a customer in the           database       PAGERTYPECODE   Code to determine the kind of pager service       BBSNUMBER   Modem number for pager notification delivery,           based on the pager type       PAGERNUMBER   Identifier number of the pager unit       PIN   PIN code for the pager unit       DISPLAYTYPE   Display type of the pager (numeric, alphanumeric,           etc.)                    
         [0026]    [0026]                         TABLE 6                       Response email Table                                RESPONSE_ID   Unique ID for a response/receipt           message to be sent to a customer       RESPONSE_SUBJECT   Subject line of the response message       RESPONSE_FROM_EMAIL   From: line of the response message       RESPONSE_BODY   Actual text of the response message                    
         [0027]    [0027]                         TABLE 7                       Resource Table                                RESOURCE_ID   Unique identifier for the resource       RESOURCE_TYPE   Type of resource (FAX, VOICE, etc.)       RESOURCE_STATUS   Status of resource Active, Inactive, etc..       RESOURCE_QUEUE_STATUS   Status of the Queue, number of messages           in queue       RESOURCE_TIME_ZONE   Time zone for the resource       RESOURCE_QUEUE_MAX   Maximum size of the resource queue       RESOURCE_ADDRESS   Address of the resource (IP address, etc.)       RESOURCE_NAME   Name of the resource       RESOURCE_EXPIRY_DURATION   Expiry duration for any message sent to           the specified resource       RESOURCE_QUEUE_IN_STATUS   Number of messages waiting to be delivered           by the resource       RESOURCE_COMMUNICATION_TYPE   Method used to communicate with resource           (HTTP, SHTTP, etc.)                    
         [0028]    [0028]                         TABLE 8                       Resource Rates Table                                RESOURCE_ID   Unique identifier for the resource       RESOURCE_PREFIX   Any digits to be dialed before an actual number       RESOURCE_CITY_NAME   Name of destination city for the message to be delivered       RESOURCE_PROVIDER_RATE   Rate for a particular city (dollars per second, etc.)       RESOURCE_MAX_DIGITS   Max number of digits allowed to be dialed       RESOURCE_AREA_CODE   Area code for the particular city                    
         [0029]    [0029]FIGS. 4 a  and  4   b  are a flow diagram of the processing performed by router/filter  23  using Tables 1-8. When a message is received it is placed into message queue  21  which is simply a storage area, the specifics of which, including the mechanism for placing the message into the queue are well known. Certain details concerning the message are also stored in a message queue table (Table 1). In step  41 , router/filter, which is a computer program running on processing server  19 , polls the message queue table for pending requests as determined by the existence of an active message in the message status field. If no message is found, after a system defined delay, the message queue table is again polled (step  43 ). Once a message has been found in the table, processing continues with step  45  by determining the message type using the message_type field in Table 1 and the file type information in Table 2. The customer is then validated using information in Table 3 in step  47 . In step  49 , currency information for the customer is obtained from Table 4. The message is then filtered for possible pager notification using the information in Table 5 in step  51 . In step  53 , Table 7 is used to check for available resources to deliver the message. In step  55 , the rates of available resources are checked to determine the least cost resource using Table 8. Then in step  59 , the message is delivered using the determined least cost resource. After the message has been delivered, or after an error in the delivery has occurred, in step  59 , a response/receipt is composed using Table 6 In step  61 , the response or receipt is delivered to the sender. The system then begins the process over again at step  41 .  
         [0030]    As noted above outbound resource  31  is equivalent to communications server  150  as described in U.S. application Ser. No. 08/829,857. The modifications made to outbound resource to enable it to operate in a system having an architecture as described herein are as follows.  
         [0031]    These changes will be described with reference to the message structure of received messages.  
         [0032]    Message Structure  
         [0033]    Each field has a value following an ‘=’ sign and is terminated by a newline character. The exception to this is the “Message” field where a newline immediately follows the ‘=’ sign and the actual message follows on the next line.  
         [0034]    The fields of a message are as follows:  
         [0035]    Password= 
         [0036]    MessageID= 
         [0037]    MessageStatus= 
         [0038]    MessageSentTimeStamp= 
         [0039]    MessageDuration= 
         [0040]    MessageLength= 
         [0041]    MessageRemoteCSID= 
         [0042]    MessageSourceCSID= 
         [0043]    MessageAttachStatus= 
         [0044]    MessageDestination= 
         [0045]    ResourceID= 
         [0046]    ResourceStatus= 
         [0047]    ResourceLastCommTimeStamp= 
         [0048]    ResourceExpiryDuration= 
         [0049]    ResourceQueueInStatus= 
         [0050]    ResourceQueueOutStatus= 
         [0051]    ResourceChannel= 
         [0052]    ResourceChannelStatus= 
         [0053]    MessageBoundary= 
         [0054]    Message= 
         [0055]    In the following explanation of the above fields, the text in brackets at the end indicates the entity providing the value for the field in the forward/reverse direction (i.e., from router/filter  23  (RF) to outbound resource  31  (RESOURCE), and from RESOURCE to RF, respectively). “NA” indicates that no value is applicable, and the text “NA” is used to populate the field. “Same” indicates that the same value is used in the reverse direction, i.e, the RESOURCE does not modify the value; it only echoes the value it receives in that field.  
         [0056]    Password—There is a fixed password pair for each RESOURCE and RF combination. RESOURCE stores the RF password in a flat text password file in a directory (jfaxom), and RF stores the RESOURCE password in the database. (RF/RESOURCE).  
         [0057]    MessageID—Unique ID, per message, generated by RESOURCE. (RESOURCE/Same).  
         [0058]    MessageStatus—Code indicating current status of the message. See Status codes below. (RF/RESOURCE)  
         [0059]    MessageSentTimeStamp—Time stamp indicating date/time the message was delivered to the final destination by RESOURCE. (NA/RESOURCE)  
         [0060]    MessageDuration—Time (in seconds) to transmit message from RESOURCE. (NA/RESOURCE)  
         [0061]    Messagelength—Number of pages transmitted by RESOURCE. (NA/RESOURCE)  
         [0062]    MessageRemoteCSID—called subscriber identification (CSID) of fax machine to which message was transmitted. (NA/RESOURCE)  
         [0063]    MessageSourceCSID—Source CSID. This may be customized per customer. (RF/Same)  
         [0064]    MessageAttachStatus—Value of “A” indicates a message is attached for delivery. (RF/RESOURCE)  
         [0065]    MessageDestination—Destination phone number. (RF/Same)  
         [0066]    ResourceID—Unique ID, per resource, stored in the database. (RF/Same)  
         [0067]    ResourceStatus—Code indicating the current status of the resource, i.e., whether it is active or not. RF uses this to determine whether further messages should be sent to RESOURCE for delivery. See Status codes below. (NA/RESOURCE)  
         [0068]    ResourceLastCommTimeStamp—Date/time of last communication between RF and RESOURCE. (RF/RESOURCE)  
         [0069]    ResourceExpiryDuration—Life of message (in minutes) on RESOURCE. If a message has not been delivered to the final destination by RESOURCE within this amount of time, the message is considered “expired” and is discarded.  
         [0070]    ResourceQueueInStatus—Number of messages waiting to be processed in an Inbox directory on RESOURCE. (NA/RESOURCE)  
         [0071]    ResourceQueueOutStatus—Number of messages waiting to be processed in an Outbox directory on RESOURCE. (NA/RESOURCE)  
         [0072]    ResourceChannelMax—Number of channels available for use on RESOURCE. (NA/RESOURCE)  
         [0073]    ResourceChannelStatus—Channel activity status, e.g., 000000011100001, where 0&#39;s indicate an idle channel and l&#39;s indicate a busy channel. (NA/RESOURCE)  
         [0074]    MessageBoundary—Text for MIME boundary. (RF/NA)  
         [0075]    Message—Actual MIME message sent by RF. If MessageAttachStatus=NA, no message follows this tag.  
         [0076]    All fields are NA if not used. Date fields are expressed in MMDDYYhhmmss format. Resource Status Codes are:  
         [0077]    A—Active  
         [0078]    I—Inactive  
         [0079]    Message Status Codes are:  
         [0080]    P—Pending  
         [0081]    H—On Hold  
         [0082]    D—Deferred  
         [0083]    R—Ready for sending to RESOURCE  
         [0084]    X—Exchanged, i.e., sent to RESOURCE but not acknowledged by it.  
         [0085]    A—Sent to RESOURCE and acknowledged by it.  
         [0086]    S—Sent (i.e., receipt for final delivery received from RESOURCE)  
         [0087]    Normal sequence for Message delivery by RESOURCE is:  
         [0088]    RF receives a request in its queue (message queue  21 ).  
         [0089]    RF sends the message to RESOURCE.  
         [0090]    RESOURCE gets message, authenticates password, and creates a new message in the Inbox directory.  
         [0091]    RESOURCE acknowledges receipt of message.  
         [0092]    RESOURCE processes the message in Inbox (MessageStatus=A, MessageAttachStatus=A).  
         [0093]    RESOURCE moves message to a Process directory for further processing.  
         [0094]    RESOURCE finishes processing message and delivers it to final destination.  
         [0095]    RESOURCE removes the message from the Process directory.  
         [0096]    RESOURCE creates a message in Outbox directory. (MessageStatus=S).  
         [0097]    If a “reply message” is to be delivered to the original sender, MessageAttachStatus=A, else MessageAttachStatus=NA. MessageID remains the same in either case.  
         [0098]    RESOURCE delivers receipt (with “reply message,” if applicable) to RF.  
         [0099]    RF receives the message and puts it in the Queue for database processing.  
         [0100]    Processing server  19  with the above described functionality may be implemented using readily available systems such as a Windows NT server or a UNIX server. Database  27  may be implemented as a database server using readily available systems such as a Windows NT server or a UNIX server running, for example a SQL database.  
         [0101]    While the present invention has been particularly described with reference to the various figures, it should be understood that the figures are for illustration only and should not be taken as limiting the scope of the invention. Many changes and modifications may be made to the invention, by one having ordinary skill in the art, without departing from the spirit and scope of the invention.