Patent Document

CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This is a continuation of U.S. application Ser. No. 11/680,033, filed Feb. 28, 2007. This application relates to and claims priority from Japanese Patent Application No. 2006-086860, filed on Mar. 28, 2006. The entirety of the contents and subject matter of all of the above is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to Internet Protocol (IP) phone systems, IP phone terminal registration methodology, and devices adaptable for use therein, including but not limited to telephone terminals and main apparatus of an IP phone system. 
         [0003]    Recent advances in IP networks such as the Internet and intranets result in development of a variety of new communication schemes via networks. In particular, the advent of IP telephones using voice over IP (VoIP) technologies leads to drastic changes in currently established telephone systems. A typical example of such IP phone systems is an extension telephone system for use in working environments of business entities. 
         [0004]    Generally, the extension IP phone system is arranged to include an IP phone system main apparatus which manages telephone terminals involved or “subscribed” therein and performs call-up control for voice communications between these phone terminals. Various types of phone terminals are available, major examples of which are a wired IP phone that is directly linkable to IP network, a telephony software application on a personal computer (PC) with a speaker(s) and a microphone connected thereto, and a radiophone handset connectable via a wireless local area network (LAN) access point. 
         [0005]    Upon establishment of such extension IP phone system, it is a must to allocate a unique IP address and extension telephone number to every telephony of the phone terminals involved. Simultaneously, it is also needed to register the setup information of these terminals to the main system controller. With all of these setup contents consolidated together while providing consistent compliance therebetween, the extension IP phone system is expected to offer proper operabilities and functionabilities required. 
         [0006]    For the allocation of extension phone numbers, it is required to design, prior to system installation, a detailed numbering plan by taking into consideration multiple base points and the exact number of working staffs. Making this numbering plan is inherently a troublesome and time-consuming work. An exemplary approach to solving this problem is to use a method for automatically allocating extension numbers in deference to setup locations of phone terminals as disclosed, for example, in JP-A-2002-315029. 
         [0007]    Regarding the telephone terminal IP address setup also, this must be carried out on a per-terminal basis in the event of system installation. A human work required therefor is also troublesome and consumes time. One thinkable method for reducing complexities in IP address allocation is to employ a specific scheme, known as the dynamic host configuration protocol (DHCP). DHCP is the protocol for assigning network information, such as IP addresses, to IP equipment linked to the IP network. Installing a DHCP device on IP network avoids the need for manual IP address setup operations as far as the telephones concerned are DHCP-supporting phone terminals. This makes it possible reduce a total amount of manual operations needed for setup of such IP telephone terminals. 
         [0008]    The DHCP device has an ability to allocate a unique IP address to the individual DHCP-supporting IP equipment that is once linked to the IP network within a predetermined area or zone. Additionally for the DHCP, expanded functions are defined by request-for-comment (RFC) 2131 and RFC 2132 standards. Use of the expanded functions makes it possible to set up in option part various kinds of data indicated by tag numbers and to notify more detailed option data. An example is that an authorized period of service (lease time) is settable to an IP address as allocated by the DHCP device. Another example is that an ability is obtained to send IP addresses of a domain name server (DNS) and default gateway accessible from the terminal side while permitting achievement of automated setup thereof. 
         [0009]    Unfortunately, the above-stated prior art approach suffers from the lack of any ability to acquire the IP address of the main apparatus in the event that an IP telephone terminal is newly registered to the IP phone system, although it is possible by DHCP to perform IP address setup and extension number allocation in an automated way. Consequently, it is still required for system maintenance service persons to perform manual telephone terminal setup operations for the individual IP phones. Upon installation of the IP phone system, a need is felt to register a great number of IP phone terminals around the same time. Usually a service person or persons perform manual operations for setup of IP phone terminals on a one-at-a-time basis; however, this approach is less in working efficiency. It has also been required to provide a setup method that is free from operation mistakes. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention was made in view of the above-noted background, and its object is to provide a technique for automating the procedure for registration of a telephone terminal(s) to an IP phone system while improving the efficiency of terminal setup works and eliminating operation mistakes. 
         [0011]    To attain the foregoing object, in accordance with one aspect of this invention, a dynamic host configuration protocol (DHCP) device is provided which operates in a way which follows. In the event that a telephone terminal is connected to IP network, the DHCP device issues a terminal registration request to a main apparatus. The main apparatus allocates thereto a telephone number and then performs terminal registration processing in an automated way. The DHCP device returns a notice of network information to the telephone terminal, which notice contains an IP address of the main apparatus and the telephone number thus allocated. The telephone terminal is responsive to receipt of the main apparatus IP address and the phone number for setting them as its own terminal information. With such an arrangement, telephone terminal registration becomes automatically executable. 
         [0012]    More specifically, for example, an IP network system is provided, which includes at least one IP phone terminal, an IP phone system main apparatus for management of the IP phone terminal, and a network information notifying device for performing notice of network information to IP equipment on an IP network. In this system, the IP phone terminal operates to transmit a connection request message to the network information notifying device. This message contains therein a media access control (MAC) address of the IP phone terminal per se and an IP address that is received from the network information notifying device and also an item of terminal information which indicates that the terminal itself is an IP phone terminal. The network information notifying device has a storage unit, in which prestored is an IP address of the IP phone system main apparatus. Upon receipt of the connection request message from the IP phone terminal, it transmits, based on the prestored IP address, a terminal registration request message to the IP phone system main apparatus. This message contains the IP phone terminal&#39;s MAC address and IP address. The IP phone system main apparatus has a management table used for management of telephone numbers. The main apparatus sends to the network information notifying device any one of a newly registered phone number and a telephone number that has already been registered in a way corresponding to the MAC address and IP address contained in the terminal registration request message. The network information notifying device also receives a telephone number and then notifies the IP phone terminal of both the telephone number and the IP address of IP phone system main apparatus being stored in the storage unit. This permits a network information processing unit of the IP phone terminal to perform setup processing based on the received phone number and the IP address of the IP phone system main apparatus. 
         [0013]    With such the arrangement for enabling the network information processing unit of the IP phone terminal to perform the telephone terminal registration setup processing based on the received phone number and the IP address of IP phone system main apparatus, it becomes possible to automatically assign an appropriate extension telephone number to the IP phone terminal by mere connection of it to the IP network, thereby enabling it to be used as operable telephone equipment. In other words, “plug-and-play” of IP phone terminal is achievable. 
         [0014]    In addition, certain kinds of operations for telephone terminal registration which have been manually performed by a system maintenance service person conventionally are no longer required, thereby making it possible to greatly save his or her time and workload need to complete the phone terminal setup required. Thus it is possible to radically eliminate or minimize human errors, such as mistakes in the process of manual setup of extension telephone numbers and/or IP addresses. 
         [0015]    Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a diagram schematically showing a configuration of an extension IP telephone system. 
           [0017]      FIG. 2  is a block diagram showing a configuration of an extension IP phone system in accordance with one embodiment of the present invention. 
           [0018]      FIG. 3  is a sequence diagram showing message transmission and reception between devices and a terminal in the embodiment of this invention. 
           [0019]      FIG. 4  is a flow diagram of terminal registration processing in a main apparatus. 
           [0020]      FIG. 5  is a diagram showing a structure of a management table of the main apparatus. 
           [0021]      FIGS. 6A to 6D  are diagrams each showing an arrangement of DHCP message. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    A currently preferred embodiment of this invention will be described in detail with reference to the accompanying figures of the drawing below. 
         [0023]    First, a configuration of one typical extension IP telephone system is schematically shown in  FIG. 1 . As shown herein, this system includes an IP phone system main apparatus  11  which manages telephone terminals  12 - 14  and  18  and performs call-up control for voice communications between these telephone terminals. The main apparatus  11  will be referred to hereinafter as a main system controller or, simply, main controller. For the phone terminals, there are various types of ones, such as wired or “fixed” IP phones  12 - 13  which are directly connectable to IP network, a telephony application program  14  operable on a PC—namely, soft-phone—with a headset  16  having speaker and microphone modules connected thereto, a radiophone handset  18  that is linkable over-the-air via a wireless LAN point  17 . 
         [0024]    Upon establishment of such extension IP phone system, it is required to allocate an IP address and an extension telephone number to the individual one of the telephone terminals  12 - 14  and  18 . It is also needed to register the setup information of these terminals to the main system controller  11  also. Only after all of these setup contents are consolidated together with consistency being retained therebetween, the extension IP phone system is expected to offer proper operabilities and functionabilities required. 
         [0025]    Explanation will next be given of an IP phone system in accordance with one embodiment of this invention. 
         [0026]    See  FIG. 2 , which is a block diagram showing a configuration of main part of the extension IP phone system embodying the invention. 
         [0027]    As shown in  FIG. 2 , this system includes a dynamic host DHCP device  210 , a main apparatus (i.e., main system controller)  220 , and an IP phone terminal  230 , which are linkable to an IP network  19 . These devices and terminal are added their unique IP addresses respectively—for example, “10.0.0.1”, “10.0.0.2”, and “10.0.0.11”, respectively. 
         [0028]    The main controller  220  is generally made up of a telephone control unit  221  which performs telephone terminal registration (i.e., registering terminal setup information as management information) and call-up connection, an operating system (OS)  222  for hardware control, a network interface card (NIC)  223  which is a device for enabling a phone terminal or a PC to the IP network  19 , and a storage unit (memory or hard disk drive)  224  for storing therein a present phone terminal registration state and extension telephone numbers. The main controller  220  uses a management table  51  (see  FIG. 5 ) in the storage unit (memory or HDD)  224  to manage extension telephone number information ( 512 ) of IP phone terminals  230  under the IP phone system and IP address information ( 513 ) to thereby realize calling connection control and voice communication management between telephone terminals. 
         [0029]    An exemplary structure of the management table  51  is shown in  FIG. 5 . As shown herein, the management table  51  is arranged to have in the same record several items of information (e.g., IP and MAC addresses) corresponding to the extension phone number information  512 . For example, an IP address “10.0.0.11” and MAC address “00:00:00:00:00:11” are allocated in a way corresponding to an extension phone number “301”; an IP address “10.0.0.12” and MAC address “00:00:00:00:00:12” are assigned corresponding to an extension phone number “302.” These extension phone numbers “301” and “302” are already assigned to IP terminals so that each has a flag  511  indicative of allocation completion. In the example of  FIG. 5 , one of the terminals with its extension number of “301” is presently in connection whereas another terminal of extension number “302” is out of connection. As for those terminals with extension numbers “303” to “305,” IP and MAC addresses are not yet allocated thereto. 
         [0030]    Turning back to  FIG. 2 , the IP phone terminal  230  is configured from a storage unit (memory or HDD)  231 , a NIC  232 , a device control unit  233 , a DHCP device  234 , an audio/voice processing unit  235  and a handset  236 . The storage unit  231  stores the terminal&#39;s own telephone number and the IP address of destination main controller  220 . The IP phone terminal  230  is IP network-linkable IP equipment with DHCP supportability. The DHCP processor  234  is communicable with DHCP device  210  for receiving various kinds of parameters to be notified from DHCP device  210 , such as IP address or else, and for setting the parameters in the storage  231  of self terminal. The IP phone terminal  230  may also be either a wired or “fixed” telephone or a soft-phone on PC. 
         [0031]    The DHCP device  210  is configured from a DHCP control unit  211 , OS  212  for hardware control, NIC  213 , and storage unit (memory or HDD)  214 . 
         [0032]    The DHCP controller  211  functions to give a unique IP address to the individual one of various types of IP equipment with DHCP supportability, which is then stored for management in the storage  214 . It also has DHCP expansion functions and is thus capable of setting several parameters in an option field(s). 
         [0033]    In this embodiment, the DHCP device  210  which prestores in its storage unit  214  the IP address “10.0.0.1” of main controller  220  communicates with the main controller  220  to execute the processing for terminal registration of the IP phone terminal  230 , and notifies by using known DHCP expanded functions the IP phone terminal  230  of both the IP address “10.0.0.1” of main controller  220  and an extension telephone number “303”, and then completes the telephone terminal registration based on this notice. A detailed procedure of this registration processing will be described with reference to FIGS.  3  and  6 A- 6 D below. 
         [0034]      FIG. 3  is a flowchart showing a series of processes in the terminal registration processing in the case where messages are transmitted and received or “transceived” among the DHCP device  210  and IP phone terminal  230  plus main controller  220  shown in  FIG. 2 . 
         [0035]    In  FIG. 3 , a subjective entity that handles the required processing in the DHCP device  210  is the DHCP controller  211 . A subjective part in charge of the processing of the IP phone terminal  230  is its DHCP processor whereas principal part handling the processing in the main controller  220  is the telephone controller  221 . 
         [0036]    A series of message transmit-and-receive (Tx/Rx) processes between the IP phone terminal  230  and the DHCP device  210  is performed using a message configuration as defined by RFC 2131 and RFC 2132, such as shown in  FIGS. 6A to 6D . 
         [0037]      FIGS. 6A-6D  are diagrams each showing the structure of a message to be transmitted and received between the IP phone terminal  230  and DHCP device  210 . 
         [0038]    Any message being sent and received between the telephone terminal and DHCP device is transmitted in the form of Ethernet™ frame  611  as defined by RFC 2131 and RFC 2132. Ethernet frame consists essentially of a destination MAC address  6111 , source MAC address  6112 , and a field  612  of IP packet(s). IP packet is made up of a destination IP address  6121 , source IP address  6122  and user datagram protocol (USP) packet  613 . This UDP packet contains a source port  6131 , destination port  6132  and message part  6133   a.    
         [0039]    Below is explanation as to a processing procedure of  FIG. 3  as a procedure for newly registering an IP phone terminal to the system. Firstly, let the IP phone terminal  230  be newly connected to the IP network  19 . In this event, the IP phone terminal  230  detects such connection and then transmits by the function of DHCP processor  234  a DISCOVER message  6133   a  toward the DHCP device  210  via over-the-air broadcasting at step S 31  of  FIG. 3 . The detection of IP phone terminal connection is enabled by providing a link-up detector in NIC part. The DISCOVER message may be arranged as shown in  FIG. 6A . 
         [0040]    When finding out the DISCOVER message  6133   a , the DHCP device  210  sends forth an OFFER message  6133   b  shown in  FIG. 6B  toward the IP phone terminal  230  to thereby notify a candidate of terminal IP address—e.g., “10.0.0.13”—at step S 32 . The notification of this IP address candidate is done by use of the OFFER message  6133   b , which contains a message along with the terminal IP address “10.0.0.13” as shown in  FIG. 6B . 
         [0041]    Upon receipt of this OFFER message, the IP phone terminal  230  acquires the terminal IP address “10.0.0.13” as sent together with the OFFER message. 
         [0042]    Subsequently at step S 33 , the IP phone terminal  230  sends a REQUEST message  6133   c  shown in  FIG. 6C , which is a formal or “official” terminal IP address acquisition request. This REQUEST message  6133   c  requires the previously received IP address “10.0.0.13” as the formal IP address while notifying that the type of terminal is “Telephone Terminal” in this case. An exemplary structure of this REQUEST message is shown in  FIG. 6C . As shown in  FIG. 6C , REQUEST message  6133   c  involves the terminal IP address “10.0.0.13” and the terminal type (phone terminal). 
         [0043]    Upon receipt of this REQUEST message  6133   c,  the DHCP device  210  first operates to determine or “judge” the terminal type. In case the terminal type is the telephone terminal, it sends a terminal registration request message to the main controller  220  at step S 34  of  FIG. 3 . This terminal registration request message have parameters as set therein, including an IP address  513  to be allocated to the IP phone terminal  230  and MAC address of IP phone terminal  230  per se. The main controller  220  is responsive to receipt of the terminal registration request, for executing terminal registration processing at step S 35  in a way shown in  FIG. 4 . Regarding the terminal registration processing, this will be described later. 
         [0044]    Upon completion of the telephone terminal registration at the main controller  220 , it notifies the DHCP device  210  of the finally acquired extension telephone number “303” at step S 36 . 
         [0045]    The DHCP device  210  sets up, as option information, the extension telephone number “303” that was received as the terminal-use formal IP address notifying message at step S 36  and the IP address “10.0.0.13” of main controller  220  being presently stored in the storage unit  214  and then sends forth an ACK message  6133   d  toward the IP phone terminal  230  at step S 37 . This ACK message is constructed as shown in  FIG. 6D . ACK message  6133   d  contains as parameters the main controller IP address “10.0.0.13” and the extension phone number “303” plus the terminal IP address “10.0.0.13”. 
         [0046]    At the IP phone terminal  230 , these parameters received at step S 37  are set up in itself at step S 38  whereby this terminal goes into the state that it is functionable as a successfully installed telephone with its extension phone number unique thereto. 
         [0047]      FIG. 4  is a diagram for explanation of a process flow of the terminal registration processing of the main system controller  220 . 
         [0048]    As shown in  FIG. 4 , the system procedure starts with step S 41  which causes the telephone control unit  221  of main controller  220  to refer to the contents of MAC address field in the management table  51  of  FIG. 5  and then determine whether MAC address is present or absent, which is contained in the terminal registration request message as received at step S 34  of  FIG. 3 . If YES at step S 41 , i.e., when the MAC address has already been registered, the procedure goes to step S 42  which returns an extension phone number of its corresponding record. Alternatively, if NO at step S 41 , that is, when the MAC address that is contained in the terminal registration request message received at step S 34  is not yet registered in the MAC address field of the management table  51 , the routine goes to step S 43  which allocates thereto a new extension telephone number. 
         [0049]    Several approaches are available to allocating such new extension number. An exemplary approach is to conduct at step S 43  a search for sequentially finding certain records with an assigned flag of “Not Yet” in the management table  51  and, if such records are found, determines an extension phone number of the first found one to be a new extension number. Then, at step S 44 , the IP address and MAC address received at step S 34  are set to the IP and MAC addresses of this record while at the same time setting the assigned flag of the same record at “Done,” which means “completed.” 
         [0050]    Next, at step S 45 , let the connection state be set to “Connect.” Note here that in view of the fact that the MAC and IP addresses are notified to the main controller  220 , it is also possible to adequately set up the extension number in an automated way by use of prior art techniques—for example, the scheme as taught from JP-A-2002-315029 which is cited in the introductory part of this description. 
         [0051]    With the processing stated above, the telephone terminal registration of the main system controller  220  is completed successfully. 
         [0052]    Although in this embodiment the main controller  220  and the DHCP device  210  are arranged to be separated from each other as shown in  FIG. 2 , similar operability and functionability are achievable in case these are integrated together and received in the same housing. 
         [0053]    It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.

Technology Category: 5