Patent Publication Number: US-2007115926-A1

Title: System and method for receiving a user message at a packet-network telephone

Description:
BACKGROUND  
      1. Field of Invention  
      The present invention relates to message communication and, more particularly, to using packet-network telephones for receiving user messages stored at a network device.  
      2. Description of Related Art  
      Voice message systems allow a calling party to store (i.e., record) a voice message during a call placed to a given voice message system. A calling party may call the given voice message system directly or, alternatively, the calling party may call a called party. In the later case, if the called party does not answer or if the called party&#39;s telephone is in use, the call to the called party can be transferred to the voice message system.  
      After a calling party&#39;s call connects to the voice message system, a voice message from the calling party can be transmitted to the voice message system for storage at the voice message system. The voice message system stores the voice message for an identified called party. If a calling party&#39;s call is placed directly to the voice message system, the voice message system may prompt the calling party to identify a called party for whom the voice message is to be stored.  
      The voice message system can provide the called party with notice that a voice message has been stored for the called party at the voice message system. Typically, the called party&#39;s telephone turns on a light source (e.g., a light emitting diode (LED)) that functions as a message waiting indicator. A light source used as a message waiting indicator, however, does not provide any information associated with the message(s) that have been stored for the called party at the voice message system.  
      A called party can call a voice message system for any number of reasons, such as to listen to new voice messages that have been stored for the called party, to delete voice messages that the called party has already heard, and/or to perform administrative functions associated with a voice message account that is established at the voice message system. The called party may call a voice message system in response to noticing a message waiting indicator on the called party&#39;s telephone.  
      During a call placed by the called party to the voice message system, before the called party can access voice messages stored for the called party, the voice message system typically requires the called party to perform one or more access/identification functions. As an example, the voice message system may require the called party to identify himself/herself, such as by entering a telephone extension number assigned to the called party. As another example, the voice message system may require the called party to enter a password associated with the called party so as to verify that the called party should be allowed to access voice messages stored for the called party.  
      Moreover, during a call placed by the called party to the voice message system, after performance of the one or more access/identification functions but before the called party can access voice message messages stored for the called party, the voice message system typically requires the called party to perform one or more selection functions. As an example, the voice message system may require the called party to select whether to listen to messages, whether to create and send a message, or whether to perform administrative functions associated with the called party&#39;s voice message account (e.g., changing the called party&#39;s password). As another example, if the called party selects to listen to messages, the voice message system may require the called party to select whether to listen to new messages (messages that the called party has not yet accessed) or whether to listen to messages that the called party has accessed and saved.  
      The inventors have discovered that the current systems and methods for accessing stored messages are more burdensome than necessary. In particular, the inventors have discovered that the need for a called party to place a call to a voice message system, and then perform access/identification functions and selection functions, just to be able to have a stored message presented to the called party, is more burdensome than necessary, especially if the called party does not have any information about the stored message prior to placing the call to the voice message system.  
     SUMMARY  
      The present invention advances over the existing art by providing an improved packet-network telephone for receiving a user message, and, a method for receiving a user message at a packet-network telephone.  
      An example embodiment of the present invention, in the form of a method comprises a method for receiving a user message at a packet-network telephone. According to the exemplary embodiment, the method includes: (i) receiving, at a packet-network telephone, a Session Initiation Protocol (SIP) message comprising an identifier that identifies a user message stored at a network device and a message transport protocol for retrieving the user message, and (ii) transmitting, from the packet-network telephone, according to the message transport protocol, a request message addressed to the network device. The request message comprises: at least a portion of the identifier so as to identify the user message, and a request for the user message to be transmitted to the packet-network telephone. The method also includes receiving the user message at the packet-network telephone. The user message is transmitted to the packet-network telephone according to the message transport protocol identified in the SIP message.  
      Another example embodiment of the present invention is a packet-network telephone for receiving a user message stored at a network device. The packet-network telephone comprises: (i) a processor, (ii) a network interface to transmit and receive messages, and (iii) data storage that stores computer-readable program instructions executable by the processor. The network interface receives a SIP message comprising an identifier. The identifier identifies a user message stored at a network device and a message transport protocol to retrieve the user message. The processor executes the program instructions to create a request message. The request message is addressed to the network device and is arranged according to the message transport protocol. The request message includes at least a portion of the user message identifier, so as to identify the user message, and a request for the user message to be transmitted to the packet-network telephone. The processor further executes the program instructions to instruct the network interface to transmit the request message. The network interface receives the user message, which is transmitted to the network interface according to the identified message transport protocol.  
      These as well as other aspects and advantages will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference where appropriate to the accompanying drawings. Further, it should be understood that the embodiments described in this summary and elsewhere are intended to be examples only and do not necessarily limit the scope of the invention.  
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
      Exemplary embodiments of the invention are described herein with reference to the drawings, in which:  
       FIG. 1  is a simplified block diagram illustrating network architecture for use in carrying out the present invention in accordance with an exemplary embodiment;  
       FIG. 2  is a simplified block diagram depicting an exemplary packet-network telephone, and in particular, users interface of the exemplary packet-network telephone;  
       FIGS. 3 and 4  depict exemplary information that can be presented on a display of the exemplary packet-network telephone;  
       FIG. 5  depicts an exemplary message presentable on a display of the exemplary packet-network telephone;  
       FIG. 6  is a simplified block diagram depicting additional details of the exemplary packet-network telephone; and  
       FIG. 7  is a flow chart depicting functions that can be carried out in accordance with an exemplary embodiment.  
    
    
     DETAILED DESCRIPTION  
      1. Exemplary Architecture  
       FIG. 1  depicts exemplary network architecture for use in carrying out the present invention. It should be understood, however, that this and other arrangements described herein are for purposes of example only. As such, those skilled in the art will appreciate that other arrangements and other elements (e.g. machines, interfaces, functions, orders, and groupings of functions, etc.) can be used instead, and some elements may be omitted altogether. Further, many of the elements described herein are functional entities that may be implemented as discrete or distributed components or in conjunction with other components, in any suitable combination and location.  
      As shown in  FIG. 1 , a packet-switched network  100  is coupled to a network device  102  and to a packet-network telephone  104 . The packet-switched network  100  transports data between a sending device (e.g., the network device  102 ) and a receiving device (e.g., the packet-network telephone  104 ). The data transmitted in the packet-switched network  100  is arranged in units of data called packets. One or more packets may define a message that is transmitted through the packet-switched network  100 .  
      Each individual packet transmitted through the packet-switched network  100  does not necessarily travel along the same route within the packet-switched network  100 . In this regard, the packet-switched network  100  does not contain a continuous or dedicated link between a sending device and a receiving device. Thus, the packet-switched network  100  differs from a circuit-switched network in that a circuit-switched network comprises a continuous and dedicated link, between a sending device and a receiving device, during a communication session.  
      As an example, the packet-switched network  100  may comprise a private Local Area Network (LAN), such as a LAN used by a business enterprise or a university. As another example, the packet-switched network  100  may comprise a Private Branch eXchange (PBX) telephone network. As yet another example, the packet-switched network  100  may comprise the Internet. Other examples of the packet-switched network  100 , as well as other examples of devices that can be coupled to the packet-switched network  100 , are also possible.  
      The network device  102  may comprise one or more serving devices (e.g., a server) to process various types of messages transmitted through the packet-switched network  100 . Processing the various types of messages may comprise: (i) receiving messages transmitted to the network device  102  via the packet-switched network  100 , and/or (ii) storing the received messages within data storage of the network device  102 , and/or (iii) retrieving messages stored in data storage of the network device  102  and transmitting the retrieved messages to the packet-switched network  100  for transmission, in turn, to the packet-network telephone  104 , and/or (iv) converting messages of a first type (e.g., e-mail messages) to messages of a second type (e.g., voice mail messages). Other examples of processing the various types of messages are also possible.  
      As an example, the network device  102  may comprise a unified message server that can process various types of user messages. User messages are messages that comprise message content for presentation to a user. Examples of the various types of user messages include (i) audible messages such as voice mail messages, or (ii) visual messages such as e-mail messages, facsimile messages, and short messaging service (SMS) messages, or (iii) audible/visual messages such as video-mail messages. Examples of the audible/visual messages may comprise messages stored as files having a “.wmv” (Windows Media Format) file extension or an “.mpeg” (Media Photographer Expert Group) file extension. Other examples of the messages that can be stored at the network device  102  are also possible.  
      The packet-network telephone  104  has the look, shape, and feel of a traditional telephone. Thus, the packet-switched telephone  104  differs from a soft-phone that is employed on a personal computer and that employs peripheral devices coupled to the personal computer. Examples of the packet-network telephone  104  include a 3COM® 3102 Business Phone, product number 3C1042A, and a 3COM® 3103 Manager Phone, product number 3C1043A, both manufactured by 3COM® Corporation, Marlborough, Mass., 01752-3064.  
       FIG. 2  illustrates details of the packet-network telephone  104 . In particular, a user interface of the packet-network telephone  104  comprises a handset  200 , a display  202 , display-dependent buttons  204 , fixed-function buttons  206 , dialing buttons  208 , a speaker  210 , and a microphone  212 .  
      The display-dependent buttons  204  comprise: (i) a first button  204 A that is labeled “A,” (ii) a second button  204 B that is labeled “B,” and (iii) a third button  204 C that is labeled “C.” The display-dependent buttons  204  may comprise a number of buttons greater than or less than three buttons. Each of the display-dependent buttons  204 A-C, when pressed, triggers the performance of a function associated with the pressed display-dependent button  204 A-C. The function associated with each of the display-dependent buttons  204 A-C can change to another function when the packet-network telephone  104  changes from a first operating mode to a second operating mode. The packet-network telephone  104  may change from the first operating mode to the second operating mode in response to the pressing of a display-dependent button  204 A-C, a fixed-function button, or for any other of a variety of reasons.  
      The fixed-function buttons  206  comprise a fourth button  206 A that is labeled  , and a fifth button  206 B that is labeled  . Pressing the fourth button  206 A triggers the performance of a “scroll up” function within the display  202 . Pressing the fifth button  206 B triggers the performance of a “scroll down” function within the display  202 . The fixed-function buttons  206  may comprise a number of buttons greater than or less than two buttons. The function associated with each of the fixed-function buttons  206  does not change when the operating mode of the packet-network telephone  104  changes from a first operating mode to a second operating mode.  
      The handset  200  comprises a microphone. A microphone, such as the microphone within the handset  200 , detects sound waves. This microphone can convert the detected sound waves into electrical signals. These electrical signals may, in turn, be converted to data packets that can be transmitted to a far-end device (e.g., another packet-network telephone) via the packet-switched network  100 .  
      The handset  200  comprises a speaker for converting electrical signals into sound waves that a user of the packet-network telephone  104  can hear. The electrical signals may be based on packets transmitted from a far-end device via the packet-switched network  100 . The packet-network telephone  104  also comprises the speaker  210  and the microphone  212  so that the packet-network telephone  104  can be operated in a hands-free mode (i.e., without using the handset  200 ). The hands-free mode allows a plurality of users (as well as a single user) to use the packet-network telephone  104  for performing communications with one or more far-end devices.  
      The display  202  may comprise one or more displays for displaying information at the packet-network telephone  104 . The display  202  can comprise any of a variety of displays. For example, the display  202  can comprise a Liquid Crystal Display (LCD), and/or an Organic Light Emitting Diode (OLED) display. Other examples of the display  202  are also possible.  
      The display  202  can display a variety of information in various arrangements.  FIGS. 3, 4 , and  5 , illustrate examples of particular arrangements for displaying a variety of information. As shown in  FIG. 3 , the display  202  can display time/user information  300  that includes (i) a current date (e.g., Feb. 18, 2006), (ii) a current time (e.g., 9:13 pm), (iii) a telephone extension assigned to the packet-network telephone  104  (e.g., Ext.: 4321), and (iv) a user name (e.g., George Johnson). The user name can indicate a user that is permanently assigned to the packet-network telephone  104 . Alternatively, the user name can indicate a user that is temporarily assigned to the packet-network telephone  104 . A user may be temporarily assigned to the packet-network telephone  104  after the user logs onto the packet-network telephone  104  and/or after the user logs onto the network device  102 .  
      The display  202  can display a message count  302  that provides an indication of how many user messages are stored at the network device  102  for a particular user of the packet-network telephone  104 . As shown in the figure, the message count  302 , in conjunction with the time/user information  300 , indicates that the user George Johnson has three (3) new messages and five (5) saved messages stored at the network device  102 . New messages can comprise messages that have not yet been presented to the user to whom the messages are addressed. Saved messages can comprise messages that (i) have been presented to the user to whom the messages are addressed, and (ii) are stored on data storage of the network device  102 . Other examples of new messages and/or saved messages are also possible.  
      The message count  302  may also provide other information about the messages stored at the network device  102 . For example, the message count  302  may indicate the types of messages (e.g., e-mail messages and/or video-mail messages) and the quantity of each type of message stored at the network device  102 .  
      The display  202  can display one or more user instructions. As an example, user instruction  304  is a user instruction identified as “Enter Password to View Message Summary.” Each user instruction displayed on the display  202  can be associated with a particular one of the display-dependent buttons  204 A- 204 C. For example, the user instruction  304  is associated with the first button  204 A. In this regard, a user can press the first button  204 A and enter a password via the dialing buttons  208  so as to display a summary of messages that have been received for the user. Other examples of user instructions and other examples of the user instructions being associated with buttons of the packet-network telephone  104  are also possible.  
       FIG. 4  illustrates the time/user information  300 , the message count  302 , and a message summary  400  being displayed on the display  202 . The message summary  400  comprises a first message listing  402 , a second message listing  404 , and a third message listing  406 . Alternatively, the message summary  400  can comprise a number of message listings greater than or less than three message listings.  
      The first message listing  402  identifies information associated with a first user message. The first user message, stored at the network device  102 , is from a person named John Doe and/or from a telephone having telephone extension number  1819 . The telephone having extension number  1819  may comprise another packet-network telephone and may reside on a PBX network that includes the packet-network telephone  104 . The first message listing  402  further indicates that the first user message was stored on Feb. 18, 2006 at 8:57 pm and that the duration of the first user message is (0:40) forty (40) seconds.  
      The second message listing  404  identifies information associated with a second user message. The second user message, stored at the network device  102 , is from a person named Jane Doe and/or from a telephone identified by the telephone number 312-555-1234. The second user message listing  404  includes a Real-Time Streaming Protocol (RTSP) Uniform Resource Indicator (URI). An RTSP URI can uniquely identify a user message stored at the network device  102 . In the second message listing  404 , the RTSP URI is “URI: RTSP XXXXXXX”. The value XXXXXXX may include any combination of alpha-numeric characters and may comprise some number of alphanumeric characters that is greater than or less than seven alphanumeric characters. Other examples of an RTSP URI are also possible.  
      The third message listing  406  identifies information associated with a third user message. The third user message, stored at the network device  102 , is from a person named Jim Doe who has an e-mail address of Jim_Doe@company.com.” The third user message was stored at the network device  102  on Feb. 17, 2006 at 9:30 am. The third user message may comprise an e-mail message. The third message listing  406  may include other information (not shown) about the third user message such as information that indicates: (i) the third user message includes an attached document, such as an Adobe Acrobat® PDF document, (ii) the number of words in the third user message, and/or (iii) a time that the sender created the third user message.  
      Each of the first message listing  402 , the second message listing  404 , and the third message listing  406 , may display additional information associated with a particular user message stored at the network device  102 . Such additional information may indicate that the particular user message is marked for deletion and/or that the particular user message may be converted from a first form (e.g., visual) to a second form (e.g., audible). Other examples of additional information that can be displayed in the first message listing  402 , the second message listing  404 , and the third message listing  406 , are also possible.  
      The first message listing  402  is associated with the display-dependent button  204 A. The second message listing  404  is associated with the display-dependent button  204 B. The third message listing  406  is associated with the display-dependent button  204 C. In this regard, a user can press any of the display dependent buttons  204 A,  204 B, or  204 C (when the display  202  is displaying message listings as shown in  FIG. 4 ), so as to cause the packet-network telephone  104  to present the message that is associated with the pressed display-dependent button.  
      Next,  FIG. 5  depicts a portion of the first user message identified by the first message listing  402 . The display  202  may display the portion of the first user message after a user presses the display dependent button  204 A. In some cases, the display  202  may be able to display an entire user message at one time. The portion of a user message that the display  202  can display at any given time may depend on such factors as message length, font size, and size of the display  202 . Other factors may also be partially determinative whether an entire user message can be displayed on the display  202 .  
      For user messages that cannot be displayed on the display  202  in their entirety, a user can press the fourth button  206 A (scroll-up) or the fifth button  206 B (scroll-down) so as to cause the display  202  to present portions of the user message that are not being displayed at the time the fourth button  206 A or the fifth button  206 B is pressed. The symbol    500  may be displayed to indicate that additional text is available by pressing the fifth button  206 B “scroll down.” A symbol   (not shown) could be displayed to indicate that additional text is available by pressing the fourth button  206 A “scroll up.” 
      Returning back to  FIG. 2 , the dialing buttons  108  include twelve dialing buttons. Alternatively, the dialing buttons  108  may include a number of buttons greater than or less than twelve buttons. A respective signal is produced when each of the dialing buttons  108  is pressed. The dialing buttons  108  provide means for entering telephone numbers and for entering other information such as a password. Each of the dialing buttons  108  is associated with a numeral  0 - 9  inclusive, a “#” symbol, or a “*” symbol. One or more of the dialing buttons  108  can also be associated with one or more letters of an alphabet for use in entering words. Depending on the operating mode of the packet-network telephone  104 , the packet-network telephone  104  may interpret a respective signal produced upon the pressing a given dialing button to represent a numeral, a “#” symbol, a “*” symbol, a letter of an alphabet, or any other symbol or an instruction that may be associated with the given dialing button.  
      In  FIG. 6 , a packet-network telephone  600  is shown to comprise a processor  602 , data storage  604 , and a network interface  606 , all linked together via a system bus, network, or other connection mechanism  608 . The packet-network telephone  600  may be arranged as the packet-network telephone  104  described with respect to  FIGS. 1 and 2 .  
      The processor  602  may comprise one or more processors (e.g., a general purpose processor and/or a digital signal processor). The processor  602  provides means for executing computer-readable program instructions. By executing the program instructions, the processor  602  can work in cooperation with the user interface of the packet-network telephone  104 , the data storage  604 , and the network interface  606 , so as to carry out the functions described herein.  
      The data storage  604  may comprise a computer-readable storage medium such as a magnetic disc, an optical disc, organic memory, and/or any other volatile or non-volatile mass storage system readable by the processor  602 . Alternatively, the data storage  604  may comprise a combination of computer-readable storage media. For example, the data storage  604  may comprise a first computer-readable storage medium located within the processor  602  and a second computer-readable storage medium that is located remote from the processor  602 . Other examples of computer-readable storage medium and other examples of computer-readable storage media combinations are also possible.  
      The data storage  604  provides means for storing computer-readable data. The data storage  604  may store computer-readable data arranged as program instructions that are executable by the processor  602 . Execution of the program instructions cause the processor  602 , alone or in combination with other devices of the packet-network telephone  600 , to carryout functions described herein. As an example, the program instructions may comprise instructions that cause the processor  602  to display a particular user message in response to the processor  602  detecting a signal produced when one of the display-dependent buttons  204  is pressed. As another example, the program instructions may comprise instructions for detecting a SIP message has been received at the network interface  606 , and, instructions for directing the network interface  606  to transmit the received SIP message to the processor  602 . Other examples of computer-readable data storable at the data storage  604  and other examples of program instructions executable by the processor  602  are also possible.  
      The data storage  604  may store computer-readable data in the form of user messages. As an example, the data storage  604  may store a user message that has been retrieved from the network device  102 . The data storage  604  may store the retrieved user message until the processor  602  executes program instructions to delete the user message from data storage  604 .  
      The network interface  606  provides an interface to the packet-switched network  100 . The network interface  606  may comprise a wired interface that physically couples the packet-network telephone  600  to the packet-switched network  100 . For example, the network interface  606  may comprise a 10 Base-T/100 Base-T2/1000 Base-LX Ethernet interface that physically couples to the packet-switched network  100 . In this regard, for example, the Ethernet interface may be arranged to comply with the Institute of Electrical and Electronics Engineers (IEEE) 802.3® standard for Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method.  
      Alternatively, or in combination, the network interface  606  may comprise a wireless air interface that interfaces to the packet-switched network  100  via a remote Ethernet interface that is (i) physically coupled to the packet-switched network  100 , and (ii) arranged to comply with the IEEE 802.3 standard. As an example, the wireless air interface may be arranged to comply with an IEEE 802.11 standard. Other examples of the network interface  606  are also possible.  
      2. Example Operation  
       FIG. 7  is a flow chart provided to illustrate some of the functions that may be carried out with an example embodiment of a packet-network telephone for receiving user messages stored at the network device  102 . Although the functions listed in  FIG. 7  are shown in a sequence from top to bottom, the listed functions may be carried out according to a sequence that differs from the sequence shown in  FIG. 7 . Moreover, one or more of the listed functions shown in the figure may be omitted or modified so as to carry out an exemplary embodiment of the present invention.  
      As shown in  FIG. 7 , block  700  involves receiving a SIP message at a packet-network telephone. The SIP message may be sent to the packet-network telephone  104  via the packet-switched network  100 . The SIP message may be sent to the packet-switched network  100  from the network device  102 . The packet-network telephone  104  receives the SIP message at the packet-network interface  606 .  
      The SIP message, received at the packet-network telephone  104 , may be arranged as a SIP message as defined by a SIP standards document such as (i) the standards document entitled Request for Comments: 2543, SIP: Session Initiation Protocol, dated March 1999, and incorporated herein by reference, and/or (ii) the standards document entitled Request for Comments: 3265, Session Initiation Protocol (SIP)—Specific Event Notification, dated June 2002, and incorporated herein by reference. Examples of the SIP message include a SIP NOTIFY message or a SIP OPTIONS message. Other examples of the SIP message are also possible.  
      The SIP message, received at the packet-network telephone  104 , comprises a user message identifier. The identifier identifies a user message stored at a network device and a message transport protocol for retrieving the user message stored at the network device. The identifier may be arranged in a variety of ways. For example, the identifier may comprise a URI to identify both a user message and a message transport protocol. The identifier may include any of a variety of URI.  
      As an example, the identifier may include an RTSP URI to identify a message transport protocol (i.e., RTSP) and to identify a particular user message stored at a network device. For instance, the RTSP URI may be arranged as “rtsp://user_message@network_device.net/message_number — 1234.” In this regard, “ftp” identifies the message transport protocol, and “message_number — 1234” identifies a particular user message stored at the network device. As another example, an RTSP URI may be arranged as “RTSP_Tag XXXX-XXX,” as shown in  FIG. 4 . Other examples of an RTSP URI are also possible.  
      As another example, the identifier may include a Hyper-Text Transfer Protocol (HTTP) URI to identify a message transfer protocol (i.e., HTTP) and to identify a particular user message stored at a network device. For instance, the HTTP URI may be arranged as “http://user_message@network_device.net/message_number — 1234.” In this regard, “http” identifies the message transport protocol, and “message_number — 1234” identifies a particular user message stored at the network device. Other examples of an HTTP URI to identify a message transport protocol and a particular user message are also possible.  
      As yet another example, the identifier may include a File Transport Protocol (FTP) URI to identify a message transport protocol (i.e., FTP) and to identify a particular user message stored at a network device. For instance, the FTP URI may be arranged as “ftp://ftp_user_message@network_device.net/message_number — 1234.” In this regard, “ftp” identifies the message transport protocol, and “message_number — 1234” identifies a particular user message stored at the network device. Other examples of an FTP URI to identify a message transport protocol and a particular user message are also possible.  
      As still yet another example, the identifier may include a SIP URI to identify a message transfer protocol (i.e., SIP) and to identify a particular user message stored at a network device. The SIP URI may take the form of sip://user_message@network_device.net/message_number — 1234. In this regard, “sip” identifies the message transport protocol and “message_number — 1234” identifies a particular message stored at the network device. The SIP URI may also identify the network device storing the user message (e.g., network_device.net). Other examples of a SIP URI are also possible.  
      The SIP message, received at the packet-network telephone  104 , may include additional information within or in combination with the identifier. Examples of the additional information include (i) a name of a person that created the user message, (ii) a time that the user message was created, (iii) a time that the user message was stored at the network device, and (iv) a time duration of the user message.  
      In an alternative embodiment, the SIP message, received at the packet-network telephone, may include a plurality of identifiers to identify a plurality of user messages and a respective message transport protocol for retrieving each of the plurality of user messages.  
      Next, block  702  involves displaying at least a portion of the SIP message content (i.e., content of the SIP message) on a display of the packet-network telephone  104 . Examples of the at least a portion of the SIP message content being displayed on the display  202  are shown in  FIG. 3  and  FIG. 4 . Displaying the at least a portion of the SIP message content allows a user of the packet-network telephone  104  to see information about at least one user message stored at the network device  102 . In this way, the user can make a selection as to which, if any, of the at least one user message the user would like to have transmitted to the packet-network telephone  104 .  
      Next, block  704  involves receiving a user-selection to select the user message from among one or more user messages that may be retrieved from the network device. The user-selection is received via a user interface of the packet-network telephone  104 . In this regard, the user-selection identifies a particular user message for which the packet-network telephone  104  should send a request message. The packet-network telephone  104  transmits the request message to the packet-switched network  100  for transmission, in turn, to the network device  102 . The request message comprises a request for the network device  102  to transmit the particular user message, identified by the user-selection, to the packet-network telephone  104 .  
      Receiving the user-selection may occur using any of a variety of methods. For example, receiving the user-selection may comprise the processor  602  detecting signals produced when a button of the packet-network telephone user interface is pressed. In this regard, the processor  602  may detect a signal produced when a given one of the display-dependent buttons  204 A- 204 C is pressed. As described above with respect to  FIG. 4 , the first message listing  402  is associated with display-dependent button  204 A, such that pressing the display-dependent button  204 A produces a signal that indicates the user desires to have the message identified by the first message listing  402  presented at the packet-network telephone  104 .  
      As another example, receiving the user-selection may comprise receiving a user-selection that is spoken into the speaker of the handset  200  or into the speaker  210 . In this regard, the packet-network telephone  104  may comprise interactive voice response (IVR) processing capabilities for discerning the user-selection from the user&#39;s spoken words. Other examples of receiving the user-selection are also possible.  
      In response to receiving the user-selection, the processor  602  may execute program instructions to create a request message. The request message is addressed to the network device that stores the user message which is selected by the user-selection. The request message is arranged according to the message transport protocol identified in the user message identifier. For instance, if the identified message transport protocol is HTTP, then the request message is arranged as an HTTP message (e.g. an HTTP GET message).  
      In the example where the user message identifier includes an RTSP URI, the request message may comprise any one of a variety of RTSP messages. The RTSP message may be arranged according to an RTSP standards document such as Request for Comments: 2326, Real Time Streaming Protocol (RTSP), which is dated April 1998 and is hereby incorporated by reference. As an example, the request message arranged as (i) an RTSP DESCRIBE message, (ii) and RTSP ANNOUNCE message, (iii) an RTSP SETUP message, (iv) an RTSP PLAY message, (v) an RTSP OPTIONS message, (vi) an RTSP GET_PARAMETER message, or (vii) an RTSP SET_PARAMETER message. Other examples of the request message arranged as an RTSP message are also possible.  
      Moreover, the request message may include at least a portion of the user message identifier so as to identify the selected message. For instance, the request message may identify a selected message by including the term “message_number — 1234” from a URI. The request message may also include a request for the network device to transmit the user message to the packet-network telephone. The request to transmit the user message may be expressly included in the request message, such as a particular bit within the request message being encoded to represent a request to transmit a user message. Alternatively, the request to transmit the user message may be implied by transmission of the URI received in the SIP message. Other examples of arranging the request message are also possible.  
      Next, block  706  involves transmitting, from the packet-network telephone, a request message addressed to the network device. The processor  602  may execute program instructions that instruct the network interface to transmit the request message. The request message may be transmitted to the packet-switched network  100  for transmission, in turn, to the network device  104 .  
      Transmitting the request message from the network interface  606  to the packet-switched network  100  may occur using various methods. For example, transmitting the request message from the network interface  606  may include broadcasting the request message over a wireless air interface, such as an 802.11 air interface. As another example, transmitting the request message from the network interface  606  may include transmitting the request message to a wired connection of the packet-switched network. Other examples of transmitting the request message are also possible.  
      Next, block  708  involves receiving the user message at the packet-network telephone, such as the packet-network telephone  600 . The user message is transmitted to the packet-network telephone  600  according to the message transport protocol identified in the user message identifier. The user message may be transmitted to the packet-network telephone  600  from the network device  102  via the packet-switched network  100 .  
      The user message may be received at the network interface  606  of the packet-network telephone  600 . After the network interface  606  receives the user message (or while the network interface is receiving the user message), the network interface  606  may provide a signal to the processor  602  to indicate the user message has been received (or is being received). In response, the processor  602  may execute program instructions to carry out storing the user message at the data storage  604  and/or to present the user message at a user interface of the packet-network telephone  600 . In the case where the user message is stored in the data storage  604 , after the user message is stored, the processor  602  may execute program instructions to present the user message at the user interface of the packet-network telephone  600 .  
      The processor  602  may also execute program instructions to carry out the functions of a converter that converts at least a portion of the user message in a first form (e.g., computer-readable data such as an encoded audio content or encoded visual content) to at least a portion of the user message in a second form (e.g., an audio signal that can be played by a speaker or a video signal that can be displayed by a display). After converting the at least a portion of the user message, the processor  602  may send the converted signal(s) to the appropriate user interface device (e.g., speaker or display) so as to present at least a portion of the user message at the user interface device of the packet-network telephone.  
      In the example where the message transport protocol is RTSP, the user message may be transmitted (e.g., streamed), from the network device  102  to the packet-network telephone  600 , according to the RTSP protocol. The user message streamed to the packet-network telephone may be presented to a user of the packet-network telephone  600  as the user message is being received. Alternatively, the packet-network telephone  600  may present the user message to a user of the packet-network telephone  600  after the packet-network telephone  600  has received the entire user message. Presentation of the user message may be carried out by an RTSP-based media player of the packet-network telephone  600 .  
      Other examples of presenting the user message to a user of the packet-network telephone, as well as other examples of what the packet-network telephone can do with a user message after the packet-network telephone receives the user message, are also possible.  
      3. Conclusion  
      Exemplary embodiments of the present invention have been described above. Those skilled in the art will understand, however, that changes and modifications may be made to the embodiments described without departing from the true scope and spirit of the present invention, which is defined by the claims.