Abstract:
A Voice over Internet Protocol (VoIP) system includes two or more VoIP terminals, a monitoring server ( 30 ), and a soft switch device ( 10 ). The soft switch is capable of determining whether or not phone number associated with at least one of the two or more VoIP terminals is predetermined to be monitored, amending information associated with communication between the two or more VoIP terminals, and establishing the communication between the two or more VoIP terminals through the monitoring server. The monitoring server is capable of reading voice data packets sent between the two or more VoIP terminals.

Description:
BACKGROUND 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to monitoring systems and monitoring methods, and more particularly to a VoIP monitoring system and a VoIP monitoring method. 
         [0003]    2. Description of Related Art 
         [0004]    Nowadays, Voice over Internet Protocol (VoIP) is becoming an increasingly popular method of communication in a phone system. Real-time Transmission Protocol (RTP) is generally used to send voice data packets in the VoIP phone system. 
         [0005]    Sometimes, it is necessary for a security department to monitor conversations on a VoIP phone system. However, there is no device or method to isolate the particular RTP data packets for monitoring the conversations on the VoIP phone system at present. As a result, it is difficult for the security department to find particular conversations they want to monitor. 
         [0006]    What is needed, therefore, is a VoIP monitoring system and a VoIP monitoring method, which allows efficient monitoring of a VoIP phone system. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a relational diagram between different modules within a VoIP monitoring system in the present invention; and 
           [0008]      FIG. 2  is a flow chart of a VoIP monitoring method in the present invention; 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    Referring to  FIG. 1 , a VoIP monitoring system  1  of an embodiment of the present invention is provided for monitoring the call of specific users determined by a security department. The monitoring system  1  includes a soft switch device  10 , a monitoring server  30  connected to the soft switch device  10  through the Internet, and a monitoring terminal  50  connected to the monitoring server  30 . The soft switch device  10  is connected to a security device  20  of the security department. The monitoring system  1  is respectively connected to a first VoIP terminal  40  and a second VoIP terminal  60  through the Internet. The first VoIP terminal  40  can communicate with the second VoIP terminal  60  through the Internet. 
         [0010]    The security device  20  stores many phone numbers targeted for monitoring, including the phone numbers of specific users determined by the security department. The first VoIP terminal  40  and the second VoIP terminal  60  both include at least one VoIP phone terminal. The soft switch device  10  is capable of receiving the call information transmitted from the first VoIP terminal  40  or the second VoIP terminal  60  through the Internet, subsequently determining whether the call information exists in the list of phone numbers targeted for monitoring. The call information includes the phone numbers and the transmission paths of the first VoIP terminal  40  and the second VoIP terminal  60 . When the soft switch device  10  receives the call information, it will compare the phone number of the first VoIP terminal  40  and/or the second VoIP terminal  60  with the phone numbers targeted for monitoring. If the phone number exists in the list of phone numbers targeted for monitoring, the soft switch device  10  will amend the call information to change the transmission paths, thereby transmitting the voice data packets from the first VoIP terminal  40  and the second VoIP terminal  60  through the monitoring server  30 . The monitoring server  30  includes a control device  31  having a voice coding and decoding function. The control device  31  includes a data interface  313  for transmitting the audible voice signals. The monitoring server  30  is connected to the soft switch device  10  through the Internet. The monitoring server  30  can transform voice data packets to PCM (Pulse Code Modulation) voice signals through the control device  31 , and transmit the PCM voice signals to the monitoring terminal  50  through the data interface  313 . The monitoring terminal  50  is provided for monitoring and recording the audible voice signals from the data interface  313  of the monitoring server  30 . The monitoring server  30  is also capable of transmitting the voice data packets to the first VoIP terminal  40  and the second VoIP terminal  60 , and as a result, it will not affect the communication between the first VoIP terminal  40  and the second VoIP terminal  60 . 
         [0011]    Before the first VoIP terminal  40  calls the second VoIP terminal  60 , the security device  20  will transmit the phone numbers targeted for monitoring to the soft switch device  10 . When the first VoIP terminal  40  calls the second VoIP terminal  60 , the first VoIP terminal  40  will transmit the call information having the phone numbers and the transmission paths of the first VoIP terminal  40  and the second VoIP terminal  60  to the soft switch device  10 . The soft switch device  10  determines whether the call information from the first VoIP terminal  10  exists in the list of numbers targeted for monitoring. If the phone number of the first VoIP terminal  40  and/or the second VoIP terminal  60  exist in the list of phone numbers targeted for monitoring, the soft switch device  10  will amend the call information to change the transmission paths of the first VoIP terminal  40  and the second VoIP terminal  60  and deliver the monitoring command to the monitoring server  30 . The communication between the first VoIP terminal  40  and the second VoIP terminal  60  will be established based on the amended call information. The voice data packets from the first VoIP terminal  40  and the second VoIP terminal  60  are transmitted through the monitoring server  30 . The monitoring server  30  transforms the voice data packets to the PCM voice signals through the control device  31 , and transmits the audible voice signals to the monitoring terminal  50  through the data interface  313 . The monitoring terminal  50  will monitor and record the audible voice signals. If the phone number of the first VoIP terminal  40  and/or the second VoIP terminal  60  do not exist in the list of phone numbers targeted for monitoring, the soft switch device  10  will establish the communication between the first VoIP terminal  40  and the second VoIP terminal  60  directly without amending the call information. 
         [0012]    Referring to  FIG. 2 , a VoIP monitoring method includes the following steps:
       Step 1: Phone numbers targeted for monitoring are stored in the soft switch device  10 ;   Step 2: The first VoIP terminal  40  calls the second VoIP terminal  60  through the Internet;   Step 3: The call information from the first VoIP terminal  40  is transmitted to the soft switch device  10  through the Internet;   Step 4: The soft switch device  10  determines whether the call information from the first VoIP terminal  40  exists on the list of phone numbers targeted for monitoring;   Step 5: If a number is recognized, the soft switch device  10  will amend the call information and deliver the monitoring command to the monitoring server  30 , the communication between the first VoIP terminal  40  and the second VoIP terminal  60  will be established through the monitoring server  30 ;   Step 6: The monitoring server  30  transforms the voice data packets from the first VoIP terminal  40  and the second VoIP terminal  60  to the PCM voice signals through the control device  31 , and transmits the audible voice signals to the monitoring terminal  50  through the data interface  313 ;   Step 7: The monitoring terminal  50  monitors and records the PCM voice signals;   Step 8: If the call information does not exist in the list of phone numbers targeted for monitoring, the soft switch device  10  will establish the communication between the first VoIP terminal  40  and the second VoIP terminal directly.       
 
         [0021]    It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.