Patent Publication Number: US-2003233417-A1

Title: System and method for signaling using instant messaging in multimedia telephony-over-lan conferences

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
     [0001] This application is related to concurrently-filed and commonly-owned patent application Ser. No.______, (Attorney Docket: 2002P02748US) titled “System and Method for Collaborating Using Instant Messaging in Multimedia Telephony-over-LAN Conferences.” 
    
    
     
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The present invention relates to telecommunications devices and, in particular, to an improved system and method for multimedia telephony-over-LAN conferences.  
       [0004] 2. Description of the Related Art  
       [0005] An effective and user-friendly way to conduct multimedia audio and/or video teleconferences has long been sought. The promulgation of the H.323 Recommendation and the Session Initiation Protocol (SIP), as well as other multimedia packet protocols, have raised hopes that multimedia audio and video conferencing may yet reach their full potentials. Typically, to teleconference using such systems, users must log in to a teleconferencing server, identify themselves as authorized parties, and be scheduled for the conference.  
       [0006] Instant Messaging (IM) allows users to log in to an Instant Messaging server and conduct a text-based “chat” session with groups associated with a user&#39;s “buddy” lists. Typically, a user logs in to the server, identifies themselves as being present, uploads a “buddy” list, and then is invited to chat with those on the buddy list.  
       [0007] Telephony systems and instant messaging systems both have advantages and circumstances of use in which one or the other might be more desirable. Typically, telephony systems and instant messaging systems are discrete systems requiring users to learn different sets of procedures for effective usage of each. Further, such systems do not typically allow for cross-system interaction. For example, while a user could establish an instant messaging session with a party while in the middle of a teleconference with that party, the instant messaging session would be wholly independent of the teleconference.  
       [0008] As such, there is a need for a telecommunications system having a greater integration of instant messaging and teleconferencing. There is a still further need for such a system to have a relatively high level of ease of use.  
       SUMMARY OF THE INVENTION  
       [0009] These and other problems in the prior art are overcome in large part by a system and method according to the present invention.  
       [0010] A telecommunications system according to an embodiment of the present invention includes a packet network; a plurality of network clients operably coupled to the packet network, the network clients including a plurality of telephony clients and an associated plurality of Instant Messaging clients. Signaling for the telephony clients is adapted to be provided by the Instant Messaging clients using Instant Messaging channels.  
       [0011] In certain embodiments, the Instant Messaging channels carry the telephony call set up and signaling. In other embodiments, the telephony call setup and signaling is separate, but applications such as whiteboarding use the Instant Messaging channels.  
       [0012] A telecommunications method according to an embodiment of the present invention comprises establishing an instant messaging session among a plurality of users; and using an instant messaging channel of the instant messaging session to establish a multimedia over IP session among the users. In certain embodiments, the multimedia over IP session comprises a whiteboarding session during a pre-established multimedia session. Sending the whiteboarding session comprises sending a whiteboarding document in a chat window of the instant messaging session and identifying the whiteboarding document as a whiteboarding document and including size and type information. On receiving, the receiving client reads the size and type information and provides the whiteboarding document to a whiteboarding application before it can be opened in a receive chat window. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0013] A better understanding of the invention is obtained when the following detailed description is considered in conjunction with the following drawings in which:  
     [0014]FIG. 1 is a block diagram of a telecommunications system according to an embodiment of the present invention;  
     [0015]FIG. 2 is a block diagram of an exemplary telecommunications client according to an embodiment of the present invention;  
     [0016]FIG. 3A and FIG. 3B are more detailed block diagrams of telecommunications clients according to embodiments of the present invention;  
     [0017]FIG. 4 is a block diagram of an exemplary telecommunications server according to an embodiment of the present invention;  
     [0018]FIG. 5 is a diagram illustrating an exemplary graphical user interface according to an embodiment of the present invention;  
     [0019]FIG. 6 is a flow diagram illustrating operation of an embodiment of the present invention;  
     [0020]FIG. 7 is a flow diagram illustrating operation of an embodiment of the present invention;  
     [0021]FIG. 8 is a diagram illustrating signaling according to an embodiment of the present invention;  
     [0022]FIG. 9 is a diagram illustrating an exemplary graphical user interface according to an embodiment of the present invention;  
     [0023]FIG. 10 is a diagram illustrating an exemplary data element according to an embodiment of the present invention;  
     [0024]FIG. 11 is a flow diagram illustrating operation of an embodiment of the present invention;  
     [0025]FIG. 12 is a diagram illustrating signaling according to an embodiment of the present invention  
     [0026]FIG. 13 is a block diagram of an MCU according to an embodiment of the present invention;  
     [0027]FIG. 14A and FIG. 14B are diagrams illustrating signaling according to embodiments of the present invention; and  
     [0028]FIG. 15 is a diagram illustrating signaling according to an embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0029] Turning now to the drawings and, with particular attention to FIG. 1, a diagram of a telecommunications system  100  according to an embodiment of the present invention is shown. The telecommunications system  100  includes a packet network such as a LAN  102  to which are coupled a plurality of network devices. In particular, shown are a server  104 , which includes an Instant Messaging server  106 , a calendar server  108 , and a telephony server  110 . In the embodiment illustrated, the server  104  couples to the Public Switched Telephone Network (PSTN) or Internet. The server  104  may also include gateway and gatekeeper, as well as multipoint control unit functionality. It is noted that, while a single server  104  is shown, the server functionality may also be implemented using a plurality of individual servers coupled to the LAN  102 . Thus, the figures are exemplary only.  
     [0030] The telecommunications system also includes a plurality of network clients, which may be implemented in a variety of configurations. For example, shown are a wireless telephone  112 , including a cordless base station  116  and a handset  114 ; a cellular telephone  118 , which couples in through a cellular network (not shown) and the PSTN; a LAN telephone  124 ; a computer  120  implementing a telephony application program; and a network client  122  implementing a CTI (computer-telephony integration) type system, including a computer  121  and a coupled telephone  123 .  
     [0031] The network clients  120 ,  122 ,  124 ,  118 ,  112  implement telephony sub-clients  126   a - 126   e , respectively, and Instant Messaging sub-clients  128   a - 128   e , respectively, as will be explained in greater detail below. More particularly, as shown in FIG. 2, each illustrated network client includes a telephony sub-client  126 , an Instant Messaging sub-client  128 , and a calendaring application  130 . A client  120  may also implement a graphical user interface  131 . In operation, the telephony sub-client or application  126  provides telephone functionality according to the appropriate standard for each device, e.g., an IP telephony standard for transmittal on the LAN  102 . For example, in some embodiments, the telephony sub-clients  126  implement the H.323 Recommendation or the Session Initiation Protocol (SIP), although other packet multimedia protocols may be employed. The Instant Messaging sub-clients  128  implement an appropriate Instant Messaging standard. As noted above, suitable Instant Messaging standards include the Netscape AOL Instant Messenger, AT&amp;T Instant Messenger, Yahoo! Pager, or Microsoft Instant Messenger. The calendar application  130  functions with the calendaring server  108 , such as Microsoft Exchange server, to schedule teleconferences and chat sessions, as will be explained in greater detail below. Suitable calendar software includes Microsoft Outlook.  
     [0032] Also coupled to the LAN  101  may be a telephony feature access server or device  103  which couples the LAN  101  to a PBX  105 , such as a Hicom PBX. A variety of PBX telephony devices  140   a,    140   b  may also couple to the PBX  105 . Devices on the network  102  may be configured to obtain their telephony services through the PBX  105  via the TFA  103 . An exemplary telephony feature access server is the Hicom Feature Access server, available from Siemens Corp., and employing the Cornet protocol. In certain embodiments, the TFA  103  may be equipped with Instant Messaging, calendaring, and VoIP capabilities in accordance with the present invention, either as a server or a network device. In what follows, for sake of simplicity, the description will focus primarily on the server  104 , it being understood that the teachings of the present invention are equally applicable to the TFA  103 .  
     [0033] FIGS.  3 A and FIG. 3B are block diagrams of exemplary network clients according to embodiments of the present invention. In particular, the client  120  of FIG. 3A is exemplary of a personal computer coupled to the network via a network interface card (or wireless network interface card). As shown, the network client  120  includes a bus  3000 , such as a PCI bus. Coupled to the bus  3000  are one or more processors  3002 ; memory  3004 , such as RAM or SRAM; a disk drive  3006 ; one or more Universal Serial Bus interfaces  3008 ; a video interface  3012 ; and a LAN interface  3010 .  
     [0034] The processor  3002  may be implemented as any of a variety of processors or controllers, including one or more x86 or Pentium-type processors and/or one or more digital signal processors. The processor  3002  implements an IM client  3126 , a telephony client  3128 , and a calendar client  3130 , according to the present invention. The software for implementing the clients may be stored on the disk drive  3006  and memory  3004  in a known manner. The video interface  3012  may couple to a monitor  3013  and display a graphical user interface  3014  executable by the processor  3002  for use with the software clients. The USB interface(s)  308  interface to I/O devices, such as microphone  3016 , speaker(s)  3018  and a keyboard  3017  and/or cursor input device  3019 . The processor may also implement a graphical user interface  3131 , as will be described in greater detail below.  
     [0035] Finally, as noted above, a network interface  3010  interfaces the network client to a network, such as a local area network (LAN). The network interface  3010  may be implemented as a wireless or wired interface. It is noted that the network client  122  (FIG. 1) is generally similar, though the telephone functionality is provided by the coupled telephone  123  rather than the software client.  
     [0036]FIG. 3B illustrates another embodiment of the network client and, particularly, a wireless client  112 . The wireless client  112  may be embodied, for example, as any wireless telephone system, including a DECT system or other system functioning, for example, in the 2.4 GHz range. The network client  112  includes a base station  116  and one or more handsets or portable units  114 . For convenience, only one such handset  114  is shown.  
     [0037] The base station  116  includes a master processor  4000   a , a transceiver  4002   a , and a network interface  4004   a . In certain embodiments, both the base station  114  and the handset  116  may be used to make telephone calls. Thus, the master processor may implement an IM client  4126   a , a telephony client  4128   a , and a calendar client  4130   a  according to embodiments of the present invention. Typically, the clients are implemented as programs stored in memory (not shown). In such an embodiment, the base station  114  will also include a display (not shown), such as an LCD display, and a keypad (not shown). In other embodiments, the base station  114  is not used directly for user interaction and thus does not include a display or full IM client, telephony client and calendar client functionality.  
     [0038] The transceiver  4002   a  functions to implement coding and decoding and generally to communicate with the handsets  114 . The network interface  4004   a  interfaces the network client  112  to the network. Thus, the network interface may be a local area network interface.  
     [0039] The handset  114  includes a master processor  4000   b , a transceiver  4002   b , a keypad  4006 , and a display  4008 . It is noted that in certain embodiments, the keypad is implemented as a “virtual” touch screen on the display  4008 . Thus the figure is exemplary only. The display is used to implement a graphical user interface for IM, telephony and calendar functionality, as will be explained in greater detail below.  
     [0040] The master processor  4000   b  includes a IM client  4126   b , a telephony client  4128   b , and a calendar client  4130   b , as will be explained in greater detail below. Typically, the clients are implemented as programs stored in memory (not shown).  
     [0041] As will be explained in greater detail below, in operation, the user can use the keypad and screen  4006 ,  4008  to set a date and parties for a conference. The network server  104  then acts to set up and coordinate the conference  
     [0042] It is noted that a cellular telephone or PDA  118  according to embodiments of the present invention is configured generally similarly. Typical cellular telephone standards include GSM and IS-136 TDMA.  
     [0043]FIG. 4 is a block diagram of an exemplary network server according to an embodiment of the present invention. As shown, the server includes an IM server  106 , a calendar server  108 , and a telephony server  110 . The server further includes on or more network interfaces  6000  for interfacing the servers to the local area network.  
     [0044] The calendar server  108  implements a central calendar application  4202  which is used to schedule teleconferences from network clients. The calendar server  108  thus further includes a memory  4203  for storing configuration information, such as lists of clients, and times of conferences, including the appropriate parties. In operation, the calendar application  4202  receives a request for a conference and stores the date and parties in the memory. The conference is then communicated to the IM server  106  and the telephony server  110 .  
     [0045] The IM server  106  likewise includes a memory  4204  for storing configuration information and for receiving “buddy” lists from IM clients. In operation, the IM client activates chat sessions among at least a subset of the parties to the teleconference, in some embodiments, receiving messages and retransmitting them to other chat parties.  
     [0046] The telephony server  110  also includes a memory  4206  for storing configuration information and calling and called party information. In operation, the telephony server receives the conference appointment time from the calendar server  108  and, at the appointed time, either arranges the system for the conference or transmits a request to the host user to begin the conference.  
     [0047] In addition, the server may include gateway  4102  and gatekeeper functionality  4104  (in an embodiment employing H.323), as well as multipoint control unit (MCU)  4106  functionality. Finally, while illustrated as a single server, each of the IM server, calendar server, and the telephony server, and the various other components, could be implemented as discrete units. Thus, the figure is exemplary only.  
     [0048] Operation of an embodiment of the present invention is explained with reference to FIG. 5 and FIG. 6. In the discussion that follows, network client  120  shall be referred to, it being understood that the teachings of the present invention are equally applicable to the other network clients and their functionality generally similar.  
     [0049] As shown in FIG. 5, the telephony client  126 , the instant messaging client  128 , and the calendar application  130  may be implemented including a graphical user interface. In operation, the user may activate one or more instant messaging windows  128 - 1 ,  128 - 2  and one or more calendar windows  130 . In a typical embodiment, the calendar application  130  and the instant messaging windows  128 - 1 ,  128 - 2  are opened from within the telephony application  126 - 1 . Thus, these applications may form an integrated part of the telephony application, or may be implemented using plug-ins. In other embodiments, these applications may be implemented using separate applications that are nonetheless adapted to communicate with one another. In still other embodiments, the calendar application or the instant messaging applications may be opened first, and the other applications from them. In the embodiment illustrated, the application further includes an address book or buddy list  402 .  
     [0050]FIG. 6 is a flow diagram illustrating operation of an embodiment of the present invention. As shown, in  602 , the IM application  128  is used to log on and provide a buddy list to the IM server  106 . In  604 , the calendar application  130  is used to schedule a teleconference using the calendar server  108 . For example, the user may set a date and identify the parties to the teleconference, and the parties may be informed of the time of the conference. At  606 , the server determines if the parties to the teleconference have IM capability. It is noted that in certain embodiments, the party information may be handed off to the IM server  106  or the telephony server  110  for them to make this determination. In  608 , the calendar server  108  informs the IM server and the telephony server of the conference. This can occur at or before the scheduled time of the conference; and may occur before step  606 . At  610 , the IM server determines a presence of IM clients, at the time of the conference. At  612 , the telephony server  110  begins the conference by calling all parties, i.e., by communicating with the telephone clients. At  614 , the chat channels are opened.  
     [0051] It is noted that, in certain embodiments, at the time of the conference, the party who called the conference may be contacted by the calendar server (e.g., via a pop up message box) and given the option of starting the conference or delaying it (i.e., if not all participants are present.).  
     [0052]FIG. 7 is a flowchart illustrating handling when a user or network client receives a conference call in embodiments of the present invention. In a step  702 , the called party receives the call, i.e., a call request and call setup signaling. In step  704 , the called party&#39;s telephony application activates and proceeds with appropriate handshake signaling to establish the call. In step  706 , the called party&#39;s IM application activates. For example, this may occur automatically, or the called party may manually click on an associated IM icon. In  708 , the called party&#39;s IM application receives the list of participants to the conference. Finally, in step  708 , the called party can select from the list to establish a chat session with various of the participants.  
     [0053] Turning now to FIG. 8, a diagram illustrating operation of an embodiment of the invention in greater detail is shown. Shown are a plurality of network clients  120 - 1 ,  120 - 2 ,  120 - 3 , an IM server  106 , a calendar server  108 , and a telephony server  110 . The network client  120 - 1  includes an IM application IM 1 , calendar application C 1 , and telephony application T 1 ; the network client  120 - 2  includes an IM application IM 2 , calendar application C 2 , and telephony application T 2 ; and the network client  120 - 3  includes an IM application IM 3 , calendar application C 3 , and telephony application T 3 .  
     [0054] In the example illustrated, it is assumed that the conference is set up at the behest of the user of network client  120 - 1 . Initially, at  501 , the user at network client  120 - 1  activates his calendar application C 1  to set a time and date for the teleconference. As noted above, any calendar application may be used. One such application is Microsoft Outlook. At  502 , the time and date are then uploaded to the calendar server  108 . A suitable calendar server is the Microsoft Exchange server.  
     [0055] In certain embodiments, the identity of the other parties to the conference is also uploaded to the server. Thus, in  504 , the calendar server  108  saves the time, date and the party information. At  506 , the IM server  106  and the telephony server  110  may verify the parties identified.  
     [0056] Next, in  508 , the calendar server  108  sends an acknowledgement to the calendar application C 1  that set the conference. At  510 , the calendar server  108  sends a message to the network client at the conference time, indicating that the conference is to begin. In response, at  512 , the telephony client T 1  sends a conference request message to the telephony server  110 . At  514 , the telephony server responds to set up the call to the originator and the other telephony clients T 2 , T 3 . The teleconference would typically be implemented in a multicast mode. The instant messaging client IM 1  then logs on to the instant messaging server  106 , at  514 . Then, at  516 , the other instant messaging applications of parties to the conference log in. The users are then able to maintain a chat session with other parties while the teleconference is ongoing.  
     [0057] It is noted that, in certain embodiments, the calendar application C 1  informs the other applications IM 1  and T 1  of the time and scheduling of the conference. The telephony application T 1  and the IM client IM 1  then begin the conference at the appointed time.  
     [0058] In certain embodiments of the present invention, signaling for a teleconference may be provided over the instant messaging channel. For example, in one embodiment, the instant messaging channel and system may be used to convey “whiteboarding” documents. “Whiteboarding documents” is a generic term for word processing, spreadsheet, presentation, or similar documents that may be used in a conference and “marked up” by various of the parties to the conference. In such an embodiment, the user can “drag” the whiteboard document to the Instant Messaging window, have the document converted into an Instant Messaging transmission format, sent along the Instant Messaging channel, and received and displayed at the other end. Typically, the document will be “intercepted” before the Instant Messaging window tries to open it, such that it can be displayed in the appropriate application&#39;s window.  
     [0059] For example, FIG. 9 illustrates a GUI  800  having a whiteboarding document  804   a  and a chat or instant messaging window  806 . The user drags the document into the chat window, as represented by the arrow  805 . In GUI  802 , representative of a receiving client, the chat window  808  is shown, with the newly received document  804   b  in its own window.  
     [0060] In operation, the whiteboarding document is packaged into an instant messaging format for transmission on the instant messaging channel. A protocol element identifies the packets as belonging to a whiteboarding application. One such protocol element is shown in FIG. 10. As shown, the element  900  includes a type field  902 , a sender field  904 , a destination field  906 , and a message or payload field  908 . The type field  902  identifies the package as belonging to a whiteboarding application and allows the receiving Instant Messaging application to port the received document to the appropriate application program.  
     [0061]FIG. 11 is a flow diagram illustrating operation of an embodiment of the present invention. At  1100 , a teleconference including Instant Messaging is set up, for example, in the manner described above. In step  1102 , a user creates a whiteboarding document, for example, through use of a word processing or spreadsheet application. At step  1104 , the user drags the document to the chat window of the Instant Messaging application. At step  1106 , the Instant Messaging application identifies the type of document and packages it into the Instant Messaging transmission format. At step  1108 , the document is sent to the destination via the Instant Messaging server. At step  1110 , the document is received and the packet type is read by the Instant Messaging application. Because the Instant Messaging application identifies the document as a whiteboarding document, it is exported to the appropriate application at  1112 . Finally, at  1114 , the document is displayed in the appropriate application window.  
     [0062] Turning now to FIG. 12, a signaling diagram illustrating operation of an embodiment of the present invention is shown. Shown are a client  120   a , a client  120   b , and a server  104 . The client  120   a  includes an Instant Messaging application IM 1 , a telephony application T 1 , and a whiteboarding application A 1 . Similarly, the client  120   b  includes an Instant Messaging application IM 2 , a telephony application T 2 , and a whiteboarding application A 2 . The server  104  includes an Instant Messaging server IMS and a telephony server Ts.  
     [0063] At  1202 , the application document is loaded from the application A 1  to the Instant Messaging program IM 1 . At  1204 , the Instant Messaging program IM 1  sends the document to the Instant Messaging server IMs. At  1206 , the Instant Messaging server sends the document to the destination Instant Messaging application IM 2 . The Instant Messaging application IM 2  then reads the header information and transfer the document to the application A 2 , at  1208 . The document can then be marked up by the client at  120   b  and sent back.  
     [0064] In certain embodiments of the present invention, the multipoint control unit (MCU)  4106  (FIG. 4) may itself be a party to the IM session. As noted above, the MCU  4106  may be implemented as a unit of the server or as a standalone unit. Such an exemplary MCU  4106  is shown in FIG. 13. The MCU  4106  includes a multipoint controller  1302 , a multipoint chat engine  1304 , and one or more memories  1306 . The multipoint controller  1302  functions to implement a multicast protocol, such as the IP multicast protocol or other multicast technique. The memory  1306  is used to store configuration information, and the like.  
     [0065] In operation, the MCU  4106  may be added as a party to the IM session automatically upon the start of the conference by the server. The MCU  4106  may then be able to respond to requests from users sent during the chat. For example, the MCU  4106  may automatically respond to requests, such as “Identify parties”, to which the MCU  4106  responds by sending an IM message back with the list of parties. Similarly, a party to the conference could send an IM message, “Please call 555-1111,” whereupon the MCU  4106  would respond by calling the number.  
     [0066] To do so, the memory  1306  may be used to store one or more configuration tables  1308  of commands and actions to be undertaken in response. When a chat message is received by the MCU  4106 , the contents of the message are perused by the IM engine  1304  to determine if an actionable command is contained therein. To read a command in a chat message, the IM chat engine  1304  can be implemented in a variety of ways. For example, the text message may include a command prefix or may simply include a predetermined text sequence. If a command is identified, then the action is carried out by the MCU controller  1302 .  
     [0067] A signaling diagram illustrating operation of an MCU according to an embodiment of the present invention is shown in FIG. 14A. In particular, shown is signaling for execution of the identification command described above. Shown are a client  120   a,  a client  120   b,  and a server  104 . The client  120   a  includes an Instant Messaging application IM 1  and a telephony application T 1 . Similarly, the client  120   b  includes an Instant Messaging application IM 2  and a telephony application T 2 . The server  104  includes an Instant Messaging server IMS and a telephony server Ts, as well as an MCU  4106 . It is noted that the MCU  4106  could form a part of a separate network entity.  
     [0068] At  1402 , the user types in the Identify command into the Instant Messaging window. At  1404 , the Instant Messaging application recognizes the entry as a functional command and transmits it to the Instant Messaging server Ims. At  1406 , the Instant Messaging server Ims likewise receives and decodes the command, sending it to the MCU  106 . At  1408 , the MCU identifies the parties to the conference, and sends the information to the Instant Messaging server at  1410 . Finally, at  1412 , the Instant Messaging server IMS sends the information to the requesting party.  
     [0069] A signaling diagram illustrating operation of an MCU according to an embodiment of the present invention is shown in FIG. 14B. In particular, shown is the signaling for using the MCU as party to the chat session to call another party. Shown are a client  120   a,  a client  120   b,  and a server  104 . The client  120   a  includes an Instant Messaging application IM 1  and a telephony application T 1 . Similarly, the client  120   b  includes an Instant Messaging application IM 2  and a telephony application T 2 . The server  104  includes an Instant Messaging server IMS and a telephony server Ts, as well as an MCU  106 .  
     [0070] At  1448 , the user types in the Call command in the instant messaging window. At  1450 , the Instant Messaging application IM 1  sends the command to the server Ims. At  1452 , the Instant Messaging server IMS sends the command to the MCU. At  1454 , the MCU reads the command and directs the Instant Messaging server to start a chat with the Instant Messaging application IM 2   1456  and a telephone connection at  1458 . The Instant Messaging destination application IM 2  and telephone application T 2  are connected to the servers at  1460 ,  1464 , respectively. The applications at client  120   a  are connected at  1462 ,  1466 .  
     [0071] While an Instant Messaging channel can be used for whitebaording applications, or via the MCU for call signaling purposes, the Instant Messaging channel can also be used for initial teleconference signaling. Shown in FIG. 15 is signaling for such an embodiment. Shown are a client  120   a,  a client  120   b,  and a server  104 . The client  120   a  includes an Instant Messaging application IM 1  and a telephony application T 1 . Similarly, the client  120   b  includes an Instant Messaging application IM 2  and a telephony application T 2 . The server  104  includes an Instant Messaging server IMS and a telephony server Ts.  
     [0072] At  1502 , the Instant Messaging application IM 1  logs in to the Instant Messaging server Ims, and sends its buddy list at  1504 . Similarly, the Instant Messaging application IM 2  logs in at  1506  and sends its buddy list at  1508 . The chat is opened between the parties at  1510 .  
     [0073] Next, if it desired to open a telephone call, the user at client  120   a  can type in or otherwise enter a command in the Instant Messenger application to call the party with whom the user is chatting. The command is sent to the Instant Messaging server IMS at  1512 . The Instant Messaging server reads the command and sends it to the telephony server TS, which then calls the parties, at  1514 . Finally, at  1516 , the media channel is opened.  
     [0074] The invention described in the above detailed description is not intended to be limited to the specific form set forth herein, but is intended to cover such alternatives, modifications and equivalents as can reasonably be included within the spirit and scope of the appended claims.