Abstract:
SMDI messages are used by the SMDI message server to generate either E-mail notifications of received messages which are forwarded to a user of the VMS or to supply VMS message status information to a voice message retrieval and forwarding system using IP messaging instead of SMDI FSK or PSK signaling. SMDI messages between a stored program controlled switching system, e.g., C.O. switch, and a voice message system are monitored by the SMDI message server of the present invention, e.g., by inserting a Tee into the SMDI link between the C.O. switch and VMS. The SMDI message server uses the directory number information and/or a message line identifier included in a received SMDI message to identify a subscriber or voice message retrieval and forwarding system which should be notified of the received SMDI message information.

Description:
RELATED APPLICATIONS 
   The present application claims the benefit of U.S. Provisional Application Ser. No. 60/269,338, filed on Feb. 16, 2001. 

   FIELD OF THE INVENTION 
   The present invention is directed to communications systems and, more particularly, to methods and apparatus for obtaining and distributing voice message status information and to controlling voice message systems. 
   BACKGROUND OF THE INVENTION 
   Voice message systems (VMSs), e.g., answering machines and voice mail systems, are commonplace in the modern communications oriented world. 
   Most VMSs allow a user to obtain message status information by calling the voice messaging system and then entering a mailbox (or account) identifier, a password and/or control signals, e.g., DTMF tones. The retrieval of message status information in this matter represents a polling operation wherein the VMS is periodically contacted and checked for waiting message information. 
   While polling a VMS for message waiting information is acceptable in many applications, e.g., in the case of home answering machines, a better approach is to provide a user of a VMS a positive indicator of a waiting message without the user having to check for the message. A frequently encountered example of such an indicator is a message waiting light on a telephone which is activated when a message is left for a VMS user and deactivated when the message is accessed or deleted. 
   Centrex is a telephone service whereby a telephone company associates several independent telephone lines together to provide PBX type functionality, e.g., telephone extension dialing, call forwarding, etc. Centrex features are provided through control of telephone lines and calls using software and a switch located at a telephone central office. For each Centrex subscriber, a separate call processing record is maintained and telephone services are provided according to the information in the call processing record. 
   Voice mail is sometimes provided as a Centrex service. To provide voice mail to Centrex subscribers, a voice mail system is often located in a telephone office and coupled to the central office switch used to service Centrex subscribers. 
   A signaling protocol, referred to as the Simplified Message Desk Interface (SMDI), described in Telecordia Technologies document titled “Simplified Message Desk Interface (SMDI)”, Generic Requirements GR-283-CORE, Issue 1, November 1999 was developed to support basic signaling of information between a message storage and retrieval system (MSRS), e.g., a voice message system (VMS), and a stored program controlled switching (SPCS) system such as a central office (C.O.) switch of the type used to provide Centrex service. The SMDI interface uses Frequency Shift Keying (FSK), Phase Shift Keying (PSK) and/or other analog signaling techniques for transmission of information according to an asynchronous serial data transmission protocol. In accordance with the SMDI protocol each word of a SMDI message consists of a start bit (space), a 7-bit standard ASCII character, an even parity bit and a stop bit (mark). 
     FIG. 1  illustrates a known prior art communications system  10 . The communications system  10  includes a public switched telephone network  40 , a business premise  23 , and a plurality of residential premises  32 ,  32 ′, and the Internet  18 . The business premise  23  includes multiple offices  24 ,  24 ′. Each office includes a computer  26 ,  26 ′. Computers  26 ,  26 ′ are coupled together and to the Internet  18  by a local area network (LAN)  25 . The offices  24 ,  24 ′ also include telephones  28 ,  28 ′ coupled to a first C.O. switch  48  of the PSTN  40 . Telephones  34 ,  34 ′, in residential premises  32 ,  32 ′, are coupled to a second C.O. switch  60  of the PSTN  40 . 
   The first and second C.O. switches  48 ,  60  are located in first and second central offices  42 ,  44  which are coupled together by a high bandwidth communications channel  56 , e.g. a fiber optic link. The PSTN  40  includes a service control point (SCP)  46  which stores customer information, e.g., Centrex call processing records (CPRs), used to provide telephone services to subscribers. The SCP  46  is coupled to the first and second C.O. switches  48 ,  60  via data lines  43 ,  45 . 
   In order to provide voice messaging services to Centrex service subscribers coupled to the first C.O. switch  48 , a voice messaging system (VMS)  50  is coupled to the C.O. switch  48  via a voice channel  54  and a SMDI link  52 . Calls to VMS service subscribers which go unanswered for a preselected period of time are supplied to the VMS  50  where the caller is provided the opportunity to leave a message for the called party. The SMDI link  52  is used to convey call data, in the form of SMDI history messages, from the C.O. switch  48  to the VMS  50 . The SMDI link  52  is also used to convey message waiting indicator (MWI) control messages from the VMS  50  to the C.O. switch  48 . 
   In particular, when an unanswered call is delivered to the VMS  50 , the C.O switch  48  transmits a SMDI call history message to the VMS over the SMDI link  52 .  FIG. 2  illustrates the format for a standard SMDI history message  200 . 
   The call history message  200  begins with the alphabetic characters MD  202 . A 7-digit message line identifier (MLI)  204  follows. The MLI  204  identifies the line to which an incoming call is terminated. It can be, e.g., a 7-digit directory number (DN) assigned to the PSTN or a 7-digit number made up of multi-line hunt group (MLHG) identifier and MLHG position identifier. MLI  204  is followed by a 1 character call type identifier  206  which indicates the reason the call was directed to the VMS. A 10-digit forwarding DN  208  is included in the message  200  when the call has been forwarded. Thus, the forwarding DN  208  is omitted in the case of direct calls. A space  209  separates the forwarding DN  208  from a calling DN number  210 . The calling DN  208  is followed by a space and a 1 character calling presentation status field  214 . The field  214  is followed by another space  216 . A calling name/presentation status field  218  is used to provide the name of the calling party which is obtained when available using known techniques. Some of the information fields may be omitted from the call history message  200  depending on the nature of the call being connected to the VMS  50  and the availability of information to populate the fields. 
     FIG. 3  illustrates the format of a SMDI MWI control message  300 . The message  300  includes an activation request identifier field  302 , a space  304  and a subscriber directory number field  306 . The activation request identifier field  302  includes the characters OP or RMV to indicate whether the message waiting indicator should be activated (“operated”) or de-activated (“removed”). The subscriber DN field includes a 10-digit directory number which is used to indicate the subscriber whose message waiting indicator is to be controlled. SMDI MWI control messages  300  are terminated by a “!” and a Control D character (not shown). 
   Use of voice messing IPs such as the VMS  50  is not limited to Centrex applications. The VMS  50  can be used to provide voice messaging services to residential telephone service customers such as users of telephones  34 ,  34 ′. Unfortunately, most residential voice messaging service subscribers lack telephones with message waiting lights which are capable of being activated by a C.O. switch. 
   One of the advantages of Centrex is that it can be used with standard telephones thereby allowing businesses to avoid the investment in more costly phones which support features such as message waiting lights. Accordingly, many business subscribers to voice messaging services provided by telephone companies find themselves confronted with having to call the VMS  50  to check for messages even though the VMS  50  supports a SMDI link  52  to the C.O. switch  48 . 
   In view of the above, it becomes apparent that there is a need for improved methods and apparatus notifying voice messaging service subscribers of waiting messages. It is desirable that at least some notification methods be supported which do not require a subscriber to poll a VMS to be notified of waiting messages. It is also desirable that at least some notification methods be supported which can be used with existing voice messaging systems, e.g., systems which support the use of SMDI. It is further desirable that new message notification methods and apparatus not interfere with existing C.O. notification via the control of message waiting lights on telephones which support such functionality. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to methods and apparatus for obtaining and distributing voice message status information and to controlling voice message systems. 
   In accordance with the present invention, SMDI messages between a stored program controlled switching system (SPCS), e.g., central office switch, and a message storage and retrieval (MSR) system, e.g., voice message system (VMS), are monitored by a SMDI message server of the present invention. 
   The SMDI message server detects SMDI messages without interfering with the communication of the messages between the C.O. switch and VMS. The messages are processed and used to generate either E-mail notifications of received messages which are forwarded to a user of the VMS or to supply message status information to a voice message retrieval and forwarding system using IP messaging including IP packets instead of SMDI FSK or PSK signaling. The IP messages generated and transmitted to a VMRAF system may include information from both SMDI MWI control messages and SMDI history messages. In this manner, the VMRAF system can be supplied with information on the identity of the party who left a message which might not be available directly from the VMS at the time the message is retrieved by the VMRAF system. 
   In accordance with the present invention information for SMDI message server users, and/or VMRAF service subscribers, is stored in a service control point (SCP) and downloaded to the VMRAF system and SMDI message server. The subscriber information downloaded from the SCP to the SMDI message server may include the E-mail address of the subscriber, the subscriber&#39;s DN, information on whether or not the subscriber is a VMRAF service subscriber and, for VMRAF service subscribers, the IP address of the VMRAF system. 
   Information downloaded from the SCP to a VMRAF system may include the DNs of VMRAF service subscribers and the E-mail address to which voice messages in the form of audio files may be forwarded using IP packets. 
   Since the SMDI message server and VMRAF system of the present invention can be used without interfering with the normal operation and SMDI messaging of known voice messaging systems, the SMDI message server and VMRAF system of the present invention can often be added to existing communications systems without the need to make expensive and costly modifications to existing hardware. 
   Various additional features and advantages of the present invention will be apparent from the detailed description which follows. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a known communications system which includes a SMDI link for providing a C.O. switch with message waiting status information. 
       FIG. 2  illustrates the format of a SMDI history message. 
       FIG. 3  illustrates the format of SMDI MWI control messages. 
       FIG. 4  illustrates a communications system implemented in accordance with the present invention, which supports advanced voice message notification and retrieval features. 
       FIG. 5  illustrates a set of exemplary Centrex call processing records which may be used in the system of  FIG. 4 . 
       FIG. 6  illustrates a SMDI message server implemented in accordance with the present invention. 
       FIG. 7  illustrates a set of subscriber information which may be used by the SMDI message server of  FIG. 6 . 
       FIG. 8  illustrates a SMDI message server routine used for providing SMDI information using IP messages. 
       FIG. 9  illustrates a voice message notification E-mail generated in accordance with the present invention. 
       FIGS. 10 and 11  illustrate IP messages including SMDI information generated in accordance with the present invention. 
   

   DETAILED DESCRIPTION 
   As discussed above, the present invention is directed to methods and apparatus for obtaining and distributing voice message status information and to controlling voice message systems. 
     FIG. 4  illustrates a communications system  400  implemented in accordance with the present invention. Various elements of the system  400  may be implemented using elements which are the same as, or similar to, the elements of the known system  10 . Such elements are identified in  FIG. 4  using the same names and reference numbers as used in  FIG. 1 . For the purposes of brevity, such elements will not be described again in detail. 
   As illustrated in  FIG. 4 , the communication system  400  includes the Internet  18 , business premises  23 , residential premises  32 ,  32 ′, the public switched telephone network (PSTN)  440 , and a voice message retrieval and forwarding (VMRAF) system  420  which are coupled together as illustrated. 
   The PSTN  440  includes a service control point (SCP)  446  which is coupled to first and second signal transfer points  442 ,  444 . The SCP  446  includes a set  447  of Centrex subscriber call processing records. The call processing records, in accordance with the present invention, include voice message notification information, as well as other information.  FIG. 5  illustrates an example of the set  447  of call processing records. 
   As illustrated in  FIG. 5 , the set  447  includes a call processing record  501 ,  501 ′ for each one of the N Centrex subscribers serviced by SCP  446 . Each call processing record includes a Centrex customer identifier  502 ,  502 ′, the subscriber&#39;s directory number  504 ,  504 ′ and a set of service information  506 ,  506 ′. In accordance with the present invention, the service information includes information  510 ,  510 ′ indicating whether or not the subscriber is a VMS service subscriber. 
   In addition, for VMS service subscribers, a VMS identifier  512 ,  512 ′ is included which indicates the VMS assigned to provide voice messaging services to the subscriber. Also included in the service information  514 ,  514 ′ is information which indicates whether the Centrex subscriber is also a voice message retrieval and forwarding (VMRAF) service subscriber. For VMRAF service subscribers, VMRAF system information  516 , e.g., the IP address of the VMRAF system which provides services to the subscriber, is included in the service information  506 . Also included in each CPR is an E-mail address  518  where the VMRAF system can E-mail voice messages and/or E-mail notifications of waiting voice messages can be sent by the SMDI message server. 
   Referring once again to  FIG. 4 , STP  44  includes a central office switch  60  as in the known system  10 . However, STP  442  is implemented in accordance with the present invention, and includes a C.O. switch  448 , a voice messaging system (VMS)  50  and a SMDI message server  460  and an RS-232 tee  455 . 
   Tee  455  is used to tap the SMDI link comprising segments  452 ,  456  between VMS  50  and C.O. switch  448  without interfering with communications over the SMDI link. Thus, by way of tee  455  and segment  454 , the SMDI message server  460  is supplied with the SMDI messages communicated between VMS  50  and C.O. switch  448 . The SMDI message server  460  uses the received SMDI messages to provide E-mail notifications of voice messages to voice messaging service subscribers who do not subscribe to the VMRAF service. It also uses the received SMDI messages to provide message information to the VMRAF system  420  as will be discussed below. 
   In the  FIG. 4  embodiment, the SMDI message server  460  is shown as being coupled directly to the LAN  25  thereby allowing the SMDI message server  460  to send E-mails to computers  26 ,  26 ′. In addition, the SMDI message server is coupled to the Internet thereby permitting E-mails to be sent via the Internet  18  to, e.g., computers  33 ,  33 ′. The Internet  18  provides a connection that is well suited for sending E-mails to customers who are not directly coupled to an intranet such as a corporate LAN. 
   With regard to VMRAF service subscribers the SMDI message server  460  forwards SMDI message information to the VMRAF system  420  so that the system  420  can receive SMDI message information by way of the Internet or an intranet in the form of IP messages. 
   SCP  446  is coupled to the SMDI message server  460 , the VMRAF system  420 , VMS  50  and C.O. switches  448  and  44  via data network connections  460 ,  462 ,  464 ,  466  and  468 , respectively. Thus, the SCP  446  can provide each of these devices with relevant subscriber information and configure them to provide services to individual Centrex customers as specified by each subscriber&#39;s CPR information. 
   In one embodiment, the SCP  446  provides the VMRAF system  420  with E-mail address information and VMS information for Centrex subscribers who are to be provided with VMRAF service. In addition to providing E-mail information to the VMRAF system, for each VMRAF service subscriber, the SCP  446  provides the SMDI message server  460  with the VMRAF service subscriber&#39;s directory number and the IP address of the VMRAF system  420  to which SMDI message information is to be forwarded by the server  460 . 
   With regard to VMS subscribers who do not subscribe to VMRAF service, the SCP  446  provides the SMDI message server  460  with directory number and E-mail address information so that the SMDI message server  460  can send them E-mail notifications of voice messages. 
   The VMRAF system  420  may be the same as, or similar to, the VMRAF system described in U.S. patent application Ser. No. 09/785,223, titled “METHODS AND APPARATUS FOR IMPLEMENTING VOICE MESSAGING USING E-MAIL”, filed on Feb. 16, 2001 and hereby expressly incorporated by reference. The VMRAF system  420  has the ability to retrieve voice messages from one or more voice messaging systems and forward the voice messages to a subscriber using IP packets, e.g., as E-mail file attachments. In some embodiments, the VMRAF system  420  maintains a local store of retrieved and forwarded voice messages in the event that a subscriber wishes to access the messages by phone by calling the VMRAF system  420 . 
   In accordance with the present invention, the VMRAF system  420  is provided with SMDI message information in the form of IP messages transmitted from SMDI message server  460 . Providing the VMRAF system  420  with SMDI message information avoids the need for the VMRAF system to poll the VMS  50  to determine when messages are waiting for a subscriber. The message server  460  supplies the VMRAF system with calling party information, such as the calling party&#39;s name and/or telephone number (directory number). Such information may not be directly available from the VMS  50  at the time a voice message is retrieved by the VMRAF system  420 . 
   The VMRAF system  420  responds to the receipt of a SMDI OP MWI message information from the SMDI message server  460  by accessing the VMS  50 , retrieving the message corresponding to the DN indicated in the OP MWI message information and forwarding the retrieved message to the subscriber, e.g., using the subscriber&#39;s E-mail address. In the case where SMDI history message information is received in addition to the SMDI OP MSI message information, the VMRAF system  420  will include, assuming the presentation status indicator permits presentation of the information, received calling party name and telephone number information in the E-mail message forwarding a retrieved voice message. 
   The VMRAF system  420  responds to the receipt of SMDI RMV MWI message information by deleting any locally stored messages, retrieved from the VMS  50 , that correspond to the subscriber identified by the DN number included in a SMDI RMV MWI message. 
   The SMDI message server  460  of the present invention will now be described in detail with reference to  FIG. 6 . The SMDI message server  460  includes a network interface card (NIC) and/or modem  602 , input/output (I/O) interface  606 , CPU  604 , and memory  608  which are coupled together by bus  603 . A display device  610  and input device, e.g., keyboard  612 , is coupled to the other components of the SMDI message server via I/O interface  606 . 
   The NIC/modem  602  couples the SMDI message server  460  to the Internet  18  and/or one or more intranets. The connection between the SMDI message server  460  and SCP  46  is an example of one intranet to which the NIC/modem  602  is coupled. The NIC/modem  602  allows the SMDI message server  460  to send and receive information over IP based networks such as the Internet  18 . Via NIC/modem  602  and the use of IP packets to convey information, the SMDI message server  460  forwards E-mail notification of voice messages to service subscribers and sends SMDI message information to the VMRAF system  420 . 
   In addition to allowing a system administrator to input and view SMDI message server information by way of devices  610 ,  612 , the I/O interface  606  allows the SMDI message server to receive and, optionally, send, SMDI messages over the SMDI link connecting the C.O. switch  448  to VMS  50 . To support SMDI link functionality, the I/O interface includes an FSK and/or PSK signal decoder and, in the case where SMDI signals are to be generated, an SFK and/or PSK signal encoder as well. 
   Memory  608  includes a SMDI message to IP/E-mail conversion routine  622  and E-mail routine  620 , VMS subscriber information  624  and a SMDI message store  626 . The CPU  604  controls operation of the SMDI message server  460  under the direction of one or more of the routines  622 ,  620  stored in the memory  608 . 
   As discussed above, some or all of the information in the set of VMS subscriber information  624 , may be supplied by the SCP  446 .  FIG. 7  illustrates an exemplary set of VMS subscriber information  626 . The set of subscriber information includes an information record  701 ,  701 ′ for each of the N subscribers serviced by the server  460 . For purposes of explanation the information record  701  for the first subscriber will be discussed. Similar information is maintained for each of the N subscribers. 
   The information  701  stored for the first subscriber includes a message line identifier  702  and a subscriber DN  704 . This information allows the server to associate SMDI messages with a particular subscriber by comparing the MLI or a DN included in a received SMDI message to the information in the subscriber database  626 . Subscriber information  701  also includes a field  706  which indicates whether or not the subscriber is a VMRAF service subscriber. If the subscriber is a VMRAF service subscriber, another field  708  includes information, e.g., the IP address, of the VMRAF system  420  assigned to service the subscriber. The subscriber information  701  also includes subscriber IP routing information  710 , e.g., the E-mail address or IP address to be used for sending E-mail messages, such as notification of voice messages, to the subscriber. 
   The SMDI message to IP/E-mail conversion routine  622  uses the subscriber information to determine where to send SMDI message information and in what format the information is to be transmitted, e.g., as a message to a VMRAF system  420  or as an E-mail notification to a subscriber. 
     FIG. 8  illustrates an exemplary SMDI message to IP/E-mail message conversion routine  622 . The routine  622  begins in step  802  when it is executed by the SMDI message server&#39;s CPU  604 . Operation proceeds from step  802  to step  804 , wherein the set of subscriber information  626  is accessed, e.g., to identify the subscribers who are to be serviced. Then in step  806 , the server  460  monitors the SMDI communications link between the VMS  50  and C.O. switch  448  for SMDI messages. 
   In step  808  a determination is made as to whether or not a SMDI message was detected. If a SMDI message is detected in step  808 , operation proceeds to step  810 . However, if no SMDI message is detected in step  808 , operation proceeds once again to monitoring step  806 . In step  810 , a determination is made as to whether the detected SMDI message is a SMDI history message (HM) or a SMDI message waiting indicator (MWI) message. 
   If the received message is a SMDI history message, operation proceeds to step  816  wherein the history message is stored in SMDI message store  626  for future use. Operation proceeds from step  816  to monitoring step  806 . 
   If the received message is determined in step  810  to be a MWI control message, operation proceeds to step  812  wherein the subscriber information  624  is accessed using the DN included in the MSI control message. In step  812 , a determination is made as to whether the subscriber to whom the DN corresponds uses a VMRAF system, which should receive the SMDI message, or if the subscriber is to receive an E-mail notification of waiting messages. 
   If the subscriber is to receive E-mail notifications of waiting messages, operation proceeds to step  814  wherein a determination is made as to whether the received SMDI message is an operate (OP) or remove (RMV) message. If the message is a SMDI RMV message, no E-mail notification needs to be sent to the subscriber and operation proceeds to step  815 . In step  815 , the HM corresponding to the RMV message, as determined by the DN included in the RMV message, is deleted from the SMDI message store  626  prior to operation returning once again to monitoring step  806 . 
   If an OP message was received, operation proceeds from step  814  to step  816  wherein the stored SMDI history message corresponding to the received OP message, as indicated by the DN in the OP message, is retrieved from the HM store  626 . After retrieval, the retrieved HM is deleted from the store in step  818 . Then, in  820 , the retrieved HM is used to generate an E-mail notification to the subscriber indicated by the OP DN that a voice message was received. The E-mail notification message may include information obtained from the retrieved history message, e.g., the name and telephone number of the calling party as well as subscriber information such as the E-mail address of the subscriber which is obtained from the subscriber information  626 . 
   Referring now to  FIG. 9 , an example of an E-mail notification message  900  is shown. The message  900  includes in the TO: field  902  the E-mail address of the VMS subscriber. In the message field  904 , the message  900  includes the name of the party who left the message, Joe Block, which is obtained from the HM&#39;s calling name field  218  and the calling party&#39;s telephone number which is obtained from the HM&#39;s call DN field  210 . Date and time information included in the message  900  may be generated from an internal clock/calendar maintained by the SMDI voice message server. 
   After generating the E-mail message, in step  821 , the E-mail notification message is transmitted to the service subscriber using E-mail routine  620  and the Internet or an intranet. Once the E-mail notification is transmitted, operation returns to monitoring step  806 . 
   If in step  812  it was determined that the subscriber identified by the DN in the received MWI control message is a VMRAF service subscriber, operation proceeds from step  812  to step  822 . In step  822  a determination is made as to whether an OP or RMV MWI control message was received. 
   If an RMV MWI message is received, in step  826  an IP message which includes the information from the received RMV message is generated. The IP message includes the IP address of the VMRAF system used by the subscriber identified by the RMV message&#39;s DN. In addition, the message includes one or more IP packets used to convey the RMV MWI message information.  FIG. 10  illustrates an exemplary message  1000  which includes VMRAF IP routing information  1002  and RMV MWI information as the payload  1004 . 
   Once the IP message  1000  is generated in step  826 , operation proceeds to step  828 . 
   If in step  822  it is determined that an SMDI OP MWI message was received, operation proceeds to step  830  wherein the HM corresponding to the OP message is retrieved from the HM store  626 . Then, in step  832 , the retrieved HM is deleted from the HM store  626 . From step  832  operation proceeds to step  834  wherein an IP message directed to the VMRAF system  420 , used by the subscriber identified by the OP message DN, is generated. 
     FIG. 11  illustrates an exemplary IP message  1100  generated in step  834 . The message  1100  includes VMRAF information  1102 , e.g., the IP address of the VMRAF system  420 , and a payload  1104  including history message information  1106  and OP MWI message information  1108 . The payload information may be transmitted as one or more IP packets and may include all or only some of the HM and OP MWI information. 
   From step  834  operation proceeds to step  828  wherein the generated IP message is transmitted to the VMRAF system, e.g., over the Internet  18  or an intranet. Operation proceeds from step  828  to monitoring step  806 . 
   While the  FIG. 8  system uses both history message and MWI control messages, a simplified system can be implemented which does not use the SMDI history message. In such a case, the VMRAF system  420  would be forwarded SMDI OP and RMV MWI message information but not SMDI HM information. Also, in such an embodiment, a VMS subscriber who did not use VMRAF system services would be notified by E-mail of a waiting message, but without the identity of the party who left the message being included in the E-mail notification. 
   In response to OP MWI message information, the VMRAF system  420  will retrieve and forward waiting voice messages as discussed above. In response to the RMV MWI message information the VMRAF system  420  will delete any locally stored copy of a forwarded message corresponding to the subscriber indicated by the DN in the RMV MSI message. 
   Numerous variations on the above described methods and apparatus are possible without departing from the scope of the invention. For example, the functionality of the VMRAF system can be combined with that of the SMDI message server to create a system which is directly responsive to SMDI messages communicated between a C.O. switch and VMS coupled thereto.