Abstract:
A method and a telecommunication system of routing data of an IP-based PBX extension to a host. The method of routing a data of an IP-based PBX extension to a host includes driving the IP-based PBX extension to request a virtual IP address from an IP sharing device, driving the IP-based PBX extension having the virtual IP address to output a packet having the data through the IP sharing device, utilizing a sender with a first IP address to deliver the packet received from the IP sharing device to the host with a second IP address through a computer network, and utilizing the host to extract the data from the packet.

Description:
BACKGROUND OF INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a method and a telecommunication system for routing data between a telecommunication extension and a telecommunication host, and more particularly, to a method and a telecommunication system for routing data between an IP-based PBX extension and a host through wired communication or wireless communication.  
         [0003]     2. Description of the Prior Art  
         [0004]     With the popularity of Internet connections, many IP-based applications are developed to provide users Internet connections anytime and anywhere. For example, Voice over Internet Protocol (VoIP) systems are developed to transmit voice efficiently over the Internet. In the prior art, each terminal in VoIP systems connects to the Internet through a physical IP address, which is provided by an Internet Service Provider (ISP). However, voice packets are transmitted through the physical IP addresses in peer-to-peer way, which lacks flexibility of network mechanism to transmit voice packets through the Internet.  
         [0005]     Concerning a local VoIP system built within a building, each VoIP terminal (e.g. a PBX extension) with a specific ID (e.g. a predetermined IP address) can be successfully identified by a host of the local VoIP system. In other words, the host is capable of arbitrating data transmission between two local PBX extensions. However, if one prior art PBX extension originally acknowledged by the host of the local VoIP system is moved to another telecommunication system, the PBX extension is unable to work properly for exchanging voice packets with the host the local VoIP system because the required connection between the host and the PBX extension is broken. Therefore, if the prior art PBX extension roams through other telecommunication systems instead of the local VoIP system, a user can not make use of the prior art PBX extension to communicate with a user utilizing a prior art PBX extension connected to the local VoIP system.  
       SUMMARY OF INVENTION  
       [0006]     It is therefore a primary objective of the claimed invention to provide a method and a telecommunication system of routing data of an IP-based PBX extension to a host to solve the above-mentioned problem.  
         [0007]     According to the claimed invention, a method of routing a data of an IP-based PBX extension to a host comprises driving the IP-based PBX extension to request a virtual IP address from an IP sharing device, driving the IP-based PBX extension having the virtual IP address to output a packet having the data through the IP sharing device, utilizing a sender with a first IP address to deliver the packet received from the IP sharing device to the host with a second IP address through a computer network, and utilizing the host to extract the data from the packet.  
         [0008]     In addition, the claimed invention provides a telecommunication system including an IP sharing device for providing a virtual IP address, an IP-based PBX extension electrically connected to the IP sharing device for requesting the virtual IP address from the IP sharing device, wherein the IP-based PBX extension having the virtual IP address is capable of outputting a packet having the data through the IP sharing device, a host, and a sender electrically connected to the IP sharing device, the sender with a first IP address capable of delivering the packet received from the IP sharing device to the host with a second IP address through a computer network, wherein the host extracts the data from the packet.  
         [0009]     It is an advantage of the claimed invention that the method and the telecommunication system can transmit voice packets to the Internet through virtual IP addresses requested from IP sharing devices. The virtual IP addresses provided by the IP sharing device are cheaper than the physical IP addresses provided by the ISP. The IP-based PBX extensions can be connected to the local host through wires according to the IEEE 802.3 protocol or be wirelessly connected to the local host through the APs according to the IEEE 802.11x protocol. In addition, the IP-based PBX extensions can also be connected to the remote host through Internet with virtual IP addresses provided by the IP sharing device. Thus, the method and the telecommunication system according to the present invention greatly improve flexibility of prior art VoIP systems through transmitting voice packets efficiently via the Internet with the help of the virtual IP addresses.  
         [0010]     These and other objectives of the claimed invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]      FIG. 1  is a block diagram of a telecommunication system according to the present invention.  
         [0012]      FIG. 2  is a flow chart illustrating operation of the telecommunication system shown in  FIG. 1 . 
     
    
     DETAILED DESCRIPTION  
       [0013]     Please refer to  FIG. 1 .  FIG. 1  is a block diagram of a telecommunication system  10  according to the present invention. The telecommunication system  10  includes a host  12  for arbitrating data (for example, voice packets) transmitted among a plurality of IP-based PBX extensions  20 ,  30 ,  50   a,    50   b,    50   c,    50   d,  wherein the IP-based PBX extensions  20 ,  30  are positioned within a local domain  13 , and the IP-based PBX extensions  50   a,    50   b,    50   c,    50   d  are positioned within a remote domain  14 . The IP-based PBX extensions within the local domain  13  are directly handled by the host  12 . The IP-based PBX extensions within the remote domain  14 , however, are indirectly handled by the host  12  with the help of the Internet  15 . As shown in  FIG. 1 , the host  12  is connected to the Internet  15  through an Internet connection device, which provides a static IP address to connect the Internet  15 . The Internet connection device is an xDSL modem  16 . However, other broad-band Internet connection devices such as the cable modem can be used to be the above-mentioned Internet connection device. For the local domain  13 , a plurality of the IP-based PBX extensions  20  are connected to the host  12  through cables, and a plurality of the IP-based PBX extensions  30  are wirelessly connected to the host  12  through an access point (AP)  18 .  
         [0014]     In addition, the telecommunication system  10  in the preferred embodiment further has a plurality of IP sharing devices  32   a,    32   b,    32   c,  a plurality of Internet connections such as xDSL modems  36   a,    36   b  and a cable modem  26 , a plurality of Hubs  34   a,    34   b,    34   c,  and a plurality of APs  38   a,    38   b.  The xDSL modems  36   a,    36   b  and the cable modem  26  respectively utilize a plurality of dynamic IP addresses to connect the Internet  15 . As shown in  FIG. 1 , these IP extensions  50   a  are wirelessly connected to the IP sharing device  32   a  through the AP  38   a  and the Hub  34   a.  Similarly, these IP-based PBX extensions  50   d  are wirelessly connected to the IP sharing device  32   c  through the AP  38   b  and the Hub  34   c.  For other IP-based PBX extensions  50   b,    50   c,  they are respectively connected to the IP sharing devices  32   b,    32   c  through the corresponding Hubs  34   b,    34   c  wired to the IP-based PBX extensions  50   b,    50   c.    
         [0015]     Before a source IP-based PBX extension is capable of transferring voice packets to a target IP-based PBX extension acknowledged by the host  12 , the source IP-based PBX extension is needed to be acknowledged by the host  12 . That is, the source IP-based PBX extension has to login the host  12  when the source IP-based PBX extension is activated. Please refer to  FIG. 2 .  FIG. 2  is the flow chart illustrating operation of the telecommunication system  10  shown in  FIG. 1 . The operation includes following steps:  
         [0016]     Step  100 : Power on an IP-based PBX extension;  
         [0017]     Step  101 : The IP-based PBX extension checks if a wired network port is connected according to an IEEE 802.3 protocol. If yes, go to step  102 ; otherwise, go to step  110 ;  
         [0018]     Step  102 : The IP-based PBX extension checks if the host  12  is directly accessible. If yes, go to step  104 ; otherwise, go to step  116 ;  
         [0019]     Step  104 : The IP-based PBX extension login the host  12 ;  
         [0020]     Step  106 : The IP-based PBX extension enters a working status, and starts performing its designed functionality;  
         [0021]     Step  108 : The IP-based PBX extension checks if the connection between the host  12  and the IP-based PBX extension is still available. If yes, go to step  106 ; otherwise, go to step  101 ;  
         [0022]     Step  110 : The IP-based PBX extension checks if a wireless network port is connected according to an IEEE 802.11x protocol. If yes, go to step  112 ; otherwise, return to step  101 ;  
         [0023]     Step  112 : The IP-based PBX extension checks if a local AP used by the host  12  is available. If yes, go to step  104 ; otherwise, go to step  114 ;  
         [0024]     Step  114 : The IP-based PBX extension checks if an AP not used by the host  12  is available. If yes, go to step  116 ; otherwise, go to step  101 ;  
         [0025]     Step  116 : The IP-based PBX extension checks if an IP sharing device such as a dynamic host configuration protocol (DHCP) server or a network address translation (NAT) server is available. If yes, go to step  118 ; otherwise, return to step  101 ;  
         [0026]     Step  118 : The IP-based PBX extension tries to ask the IP sharing device for a virtual IP. The IP-based PBX extension checks if the virtual IP address allocated by the IP sharing device is successfully received. If yes, go to step  120 ; otherwise, return to step  101 ; and  
         [0027]     Step  120 : The IP-based PBX extension tries to enter the Internet  15  through the virtual IP address. The IP-based PBX extension checks if a connection between the IP-based PBX extension and the host  12  is successfully established. If yes, go to step  104 ; otherwise, return to step  101 .  
         [0028]     The operation of the telecommunication system  10  is described as follows. For each of the IP-based PBX extensions  20 ,  30 ,  50   a,    50   b,    50   c,    50   d,  it has a wired network port for accessing a wired network and a wireless communication module for accessing a wireless network. Taking the IP-based PBX extension  50   c,    50   d  in the remote domain  14  for example, the IP-based PBX extension  50   c  can be electrically connected to the Hub  34   c  through a cable, and the IP-based PBX extension  50   d  can be electrically connected to the Hub  34   c  through a wireless connection between the AP  38   b  and the IP-based PBX extension  50   d  and a wired connection between the AP  38   b  and the Hub  34   c.  Suppose that the IP-based PBX extension  50   d  within the remote domain  14  is powered on (step  100 ). Then, the IP-based PBX extension  50   d  finds out that no cable is connected to the wired network port (step  102 ). Therefore, a process for building a connection between the IP-based PBX extension  50   d  and the host  12  according to the IEEE 802.3 protocol is unable to work. Then, the IP-based PBX extension  50   d  checks if the local AP  18  used by the host  12  is accessible through the IEEE 802.11x protocol (step  112 ). It is clear that the IP-based PBX extension  50   d  is positioned within the remote domain  14  and is far away from the AP  18 . The IP-based PBX extension  50   d,  therefore, is unable to locate the wanted AP  18 .  
         [0029]     In the preferred embodiment, the IP-based PBX extension  50   d  starts searching any available APs around the IP-based PBX extension  50   d  (step  114 ). As shown in  FIG. 1 , the AP  38   b  is close to the IP-based PBX extension  50   d,  and is available to the IP-based PBX extension  50   d.  Therefore, the wireless connection is successfully built between the IP-based PBX extension  50   d  and the AP  38   b.  Then, the IP-based PBX extension  50   d  finds an available IP shearing device  32   c,  and starts requesting for a virtual IP address (steps  116 ,  118 ). After the wanted virtual IP address is successfully assigned to the IP-based PBX extension  50   d,  the IP-based PBX extension  50   d  tries to enter the Internet  15  (step  120 ). If the IP-based PBX extension  50   d  has been correctly connected to the Internet  15  through the Hub  34   c,  the IP sharing device  32   c,  and the cable modem  26 , the IP-based PBX extension  50   d  is capable of accessing the host  12 . That is, the IP-based PBX extension  50   d  performs step  104  to login the host  12  (step  104 ). After the IP-based PBX extension  50   d  is fully acknowledged by the host  12 , the IP-based PBX extension  50   d  starts performing its designed function for delivering voice packets (step  106 ). In the end, the IP-based PBX extension  50   d  located within the remote domain  14  communicates with the host  12  and works normally with the help of the virtual IP address provided by the IP sharing device  32   c.    
         [0030]     Consider that the IP-based PBX extension  50   b  instead of the IP-based PBX extension  50   d  is powered on (step  100 ). Under this situation, the IP-based PBX extension  50   b  finds out that a cable is electrically connected to the wired network port through the IEEE 802.3 protocol (step  102 ). Therefore, the IP-based PBX extension  50   b  begins checking if the host  12  is directly available (step  102 ). As shown in  FIG. 1 , the IP-based PBX extension  50   b  is located within the remote domain  14  instead of the local domain  13 . In other words, the IP-based PBX extension  50   b  is unable to directly access the host  12  through the cable connected to the wired network port. Then, the IP-based PBX extension  50   b  finds an available IP shearing device  32   b,  and starts requesting for a virtual IP address (steps  116 ,  118 ). After the wanted virtual IP address is successfully assigned to the IP-based PBX extension  50   b,  the IP-based PBX extension  50   b  tries to enter the Internet  15  (step  120 ). If the IP-based PBX extension  50   d  has been correctly connected to the Internet  15  through the Hub  34   b,  the IP sharing device  32   b,  and the xDSL modem  36   b,  the IP-based PBX extension  50   b  is capable of accessing the host  12 . That is, the IP-based PBX extension  50   b  performs step  104  to login the host  12  (step  104 ). After the IP-based PBX extension  50   b  is fully acknowledged by the host  12 , the IP-based PBX extension  50   b  starts performing its designed function for delivering voice packets (step  106 ). In the end, the IP-based PBX extension  50   b  located within the remote domain  14  communicates with the host  12  and works normally with the help of the virtual IP address provided by the IP sharing device  32   b.    
         [0031]     In addition, when the IP-based PBX extensions  50   a,    50   b,    50   c,    50   d  transmit voice data to the host  12  corresponding to a static IP address through the Internet  15 , the IP-based PBX extensions  50   a,    50   b,    50   c,    50   d  will add corresponding virtual IP addresses to the voice data. Taking the IP-based PBX extension  50   a  for example, the voice data outputted from the IP-based PBX extension  50   a  includes identification information. The voice packets containing the voice data generated from the IP-based PBX extension  50   a  are then transmitted via the Internet  15 . Please note that when a voice packet is outputted from the xDSL modem  36   a,  each of the voice packets includes the virtual IP address of the IP-based PBX extension  50   a,  the dynamic IP address of the xDSL  36   a,  and the static IP address of the xDSL modem  16 . Therefore, the voice packets are received by the xDSL modem  16  through the static IP address recorded in each voice packet corresponding to the IP-based PBX extension  50   a.  Thus, the host  12  extracts the identification information from the voice packets to acknowledge that the voice data are actually transmitted from a supported IP-based PBX extension, that is, the IP-based PBX extension  50   a.  Similarly, the host  12  can also communicate with the IP-based PBX extension  50   a  through the above-mentioned virtual IP address of the IP-based PBX extension  50   a,  the above-mentioned dynamic IP address of the xDSL  36   a,  and the above-mentioned static IP address of the xDSL modem  16 .  
         [0032]     Please note that the IP-based PBX extensions  20  can be connected to the local host by cables according to the IEEE 802.3 protocol or be wirelessly connected to the local host through the AP  18  according to the IEEE 802.11x protocol. As shown in  FIG. 2 , an available local connection means is checked first (steps  101 ,  110 ,  112 ). If the available local connection means is found, an activated IP-based PBX extension can directly communicate with the host  12  without the help of the Internet  15 .  
         [0033]     In contrast to the prior art, the claimed method and the claimed telecommunication system of routing data outputted from IP-based PBX extensions to the host can transmit voice packets to the Internet through virtual IP addresses. The virtual IP addresses provided by the IP sharing device are cheaper than the physical IP addresses provided by the ISP. In addition, the claimed method and the claimed telecommunication system greatly improve flexibility of prior art VoIP systems through transmitting voice packets efficiently via the Internet with the help of virtual IP addresses.  
         [0034]     Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teachings of the invention. Accordingly, that above disclosure should be construed as limited only by the metes and bounds of the appended claims.