Patent Publication Number: US-2011051719-A1

Title: Providing a call service in a communication network

Description:
CLAIM OF PRIORITY 
     This application claims the benefit of Korean Patent Application No. 10-2009-0080354 filed on Aug. 28, 2009, which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     The present disclosure relates to call services in a communication network, and more particularly, to methods and apparatus for providing company call services in an integrated wireless and wired network. 
     As wireless communication technology develops, most people now have a wireless communication device and use wireless communication services, such as a mobile voice or video call. Along with such developments in wireless communication technology, wired communication technology is also developing as an Internet Protocol (IP) based Next Generation Network (NGN). As such, wireless and wired communication technologies are now being integrated based on IP technology. Accordingly, employees&#39; personal wireless communication devices are commonly used for business purposes even though companies provide wired telephones to their employees. 
     However, employees may not be willing to use their personal wireless devices for business purposes because of: 1) the cost of telephone bills for business-related usages that may have to be covered by the employees; 2) the possible invasion of privacy by exposing their personal wireless telephone numbers; or 3) the inconvenience of receiving irrelevant business calls after moving to other departments or jobs. 
     On the other hand, there are also several issues for using employees&#39; personal wireless communication devices for business purposes from the companies&#39; point of view. For example, if a company covers its employees&#39; wireless telephone bills, the company may also end up covering employees&#39; personal usage of wireless devices. Additionally, the company risks losing its current clients because the clients&#39; calls will remain to be directed to the employee&#39;s personal wireless device even after the employee leaves the company. Particularly, since the clients&#39; information is stored in the previous employee&#39;s personal wireless device, the successor would not be able to immediately and efficiently resume the previous employee&#39;s work. 
     SUMMARY 
     It has been realized that what is needed in order to solve this problem is to provide a method and system for providing company call service in an integrated wireless and wired network. 
     In accordance with the disclosure, the method may include steps of receiving a request from a wireless device of an employee to connect to a client&#39;s device; retrieving a wired telephone number of the employee from an address book database; and connecting the client&#39;s device and the wireless device of the employee, whereby the wired telephone number being indicated as a caller&#39;s telephone number. 
     In another embodiment of the disclosure, the method may include steps of receiving a signal having a wired telephone number of an employee as a recipient&#39;s telephone number; calling a wired device of the employee, the wired device having the wired telephone number; retrieving a wireless telephone number of the employee from an address book database if no response is received from the wired device; and calling a wireless device of the employee, the wireless device having the wireless telephone number. 
     In another embodiment of the disclosure, the method may include steps of receiving a signal having a wired telephone number of an employee as a recipient&#39;s telephone number; retrieving a wireless telephone number of the employee from an address book database; calling a wireless device and a wired device of the employee simultaneously, wherein: the wired device having the wired telephone number, and the wireless device having the wireless telephone number; receiving a response from at least one of the wireless and the wired device; and connecting the responded device with a caller&#39;s device. 
     In accordance with the disclosure, the system may include an address book database for storing a wireless telephone number and a wired telephone number for a corresponding employee; and a management server for connecting a wireless device of the employee to a client&#39;s device upon receipt of a request from the wireless device to connect to the client&#39;s device, wherein: the management server being capable of retrieving the wired telephone number of the employee from the address book database, and the wired telephone number being indicated as a caller&#39;s telephone number. 
     In another embodiment of the disclosure, the system may include an address book database for storing a wireless telephone number and a wired telephone number for a corresponding employee; and a management server for connecting the employee with a client upon receipt of a request including the wired telephone number of the employee, wherein: the wired telephone number being indicated as a recipient&#39;s telephone number, the management server calls a wired device of the employee, and if no response is received, the management server retrieves the wireless telephone number of the employee from the address book database and calls a wireless device of the employee. 
     In another embodiment of the disclosure, the system may include an address book database for storing a wireless telephone number and a wired telephone number for a corresponding employee; and a management server for connecting the employee with a client upon receipt of a request including the wired telephone number of the employee, wherein: the wired telephone number being indicated as a recipient&#39;s telephone number, the management server retrieves the wireless telephone number of the employee from the address book database and calls a wireless device and a wired device of the employee simultaneously, and if a response is received from at least one of the wireless device and the wired device, the management server connects the responded device with a caller&#39;s device. 
     The disclosure in this specification can be implemented to realize one or more of the following advantages. For example, the disclosure can be implemented to allow a company to effectively manage its important client information by processing employees&#39; calls with a central system. Employees may also use the company&#39;s wired telephone numbers as their account telephone numbers instead of using their personal wireless telephone number for business purposes. This allows employees&#39; privacy to be protected, and the client information can effectively be maintained with the company even after employees leave. 
     The disclosure can also be implemented to effectively reduce cost of telecommunication bills by processing outgoing calls with the central system, which allows personal and business calls to be distinguished. 
     This general and specific disclosure can be implemented using an apparatus, a method, a system, or any combination of an apparatus, methods, and systems. The details of one or more implementations are set forth in the accompanying drawings and the description below. Further features, aspects, and advantages will become apparent from the description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a company call service system according to one embodiment of the present disclosure. 
         FIG. 2  illustrates an example of a flow chart describing a method of call connection between employees in the system presented in  FIG. 1 . 
         FIG. 3  illustrates another example of a signal flow chart describing a method of call connection between employees in the system presented in  FIG. 1 . 
         FIG. 4  illustrates a company call service system according to another embodiment of the present disclosure. 
         FIG. 5  illustrates an example of a flow chart describing a method of call connection from an employee to a client in the system presented in  FIG. 4 . 
         FIG. 6  illustrates a company call service system according to another embodiment of the present disclosure. 
         FIG. 7  illustrates an example of a flow chart describing a method of call connection from a client to an employee in the system presented in  FIG. 6 . 
         FIG. 8  illustrates another example of a flow chart describing a method of call connection from a client to an employee in the system presented in  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
       FIG. 1  illustrates a company call service system according to one embodiment of the present disclosure. According to the company call service system described in  FIG. 1 , the system may include a functional unit, such as a management server  140  and various networks  110 ,  120 ,  130  that connect the management server  140  with wired and wireless devices  153 ,  155 ,  157 . The management server  140  is coupled to a database, such as an address book database  141 . The management server  140  communicates with the wireless devices  153 ,  157  via circuit switched network  110  that provides wireless telephone service and packet network  120  that provides data service. The management server  140  communicates with the wired device  155  via Voice over Internet Protocol (VoIP) network and/or Public Switched Telephone Network (PSTN)  130 . Detailed description of such networks  110 ,  120 ,  130  is omitted herein since such networks are well known in the art. 
     For the exemplary system described in  FIG. 1 , the wireless communication devices  153 ,  157  and the wired communication device  155  are assumed to be used by employees of a company. It is also assumed that the wireless device  157  is used by employee A and that the wireless device  153  and the wired device  155  are used by employee B. Also, the system is assumed to illustrate an example of the call connection attempt between employees A and B. 
     The employees&#39; wireless devices  153 ,  157  may have client programs that may retrieve information in the address book database  141  by connecting with the management server  140  via the packet network  120 . The client program can also request a call connection. Call connections using the client programs are described as business mode, and the connections without using the client programs are described as personal mode. 
     If the wireless device  157  is connected to the management server  140  via the packet network  120  using the client program, a screen is displayed on the wireless device  157  to retrieve telephone numbers of employees and/or clients, as described in  FIG. 1 . When the user enters the name of the recipient, the client program sends this information to the management server  140 . 
     The management server  140  manages an address book by storing it in the address book database  141 . The address book may include information of employees and clients, e.g., telephone numbers and email addresses. The management server  140  also stores employees&#39; wireless telephone numbers and wired telephone numbers in the address book database  141 . As such, when employee B′s name is entered at the wireless device  157 , the management server  140  may retrieve the wired and/or the wireless telephone number that corresponds to the employee B′s name from the address book database  141 . The management server  140  may send the retrieved number to the wireless device  157 . Then, the server  140  may receive a request for a call from the wireless device  157 . 
     When the management server  140  receives a request from employee A′s wireless device  157  to call employee B′s wired device  155 , the management server calls employee A′s wireless device  157  via circuit switched network  110  and simultaneously calls employee B′s wired device  155  via wired communication networks  130  and PBX  151 . If there is no response from employee B′s wired device  155 , the management server  140  retrieves employee B′s wireless telephone number from the address book database  141 . Then, the server  140  calls employee B′s wireless device  153  via circuit switched network  110  and connects employee B′s wireless device  153  with employee A′s wireless device  157 . 
     Accordingly, although not described in  FIG. 1 , the management server  140  may include a search engine to retrieve information from the address book, a web service module to provide an address book search service for the wireless devices  153 ,  157 , and a signal processing module to connect the devices  153 ,  155 ,  157  by calling them. The management server  140  may be implemented by intelligent network apparatus or a company&#39;s intra private network. The management server  140  may include a computer-readable medium containing instructions that, when executed, perform the foregoing methods. The implementations, however, are not limited to the above examples. 
     In another embodiment of the disclosure, when the management server  140  receives a request from employee A′s wireless device  157  to call employee B′s wireless device  153 , the management server  140  retrieves employee B′s wireless telephone number from the address book database  141  and calls employee B′s wireless device  153  and wired device  155  simultaneously. If there is a response from any one of employee B′s devices  153  and  155 , the management server  140  connects the responsive device with employee A′s wireless device  157  and disconnects the call between the server  140  and the non-responsive device. 
       FIG. 2  illustrates an example of a flow chart describing a method of call connection between employees in the system illustrated in  FIG. 1 . As described in  FIG. 2 , employee A uses the client program on the wireless device  157 . The client program establishes connection to packet network  120  (S 201 ), then to the management server  140  via packet network  120  (S 203 ). 
     As the wireless device  157  is connected to the management server  140 , the server  140  sends initial screen to the wireless device  157  for an address book search. As described in  FIG. 1 , the initial screen includes a search menu for employees and clients. If employee A enters employee B′s name for a search, an address book search request including employee B′s name is sent to the management server  140  by the client program (S 205 ). 
     Upon receipt of the request including the entered name, the management server  140  retrieves the telephone number corresponding to the entered name from the address book database  141 . Then, the server  140  sends the retrieved telephone number to employee A′s wireless device  157  (S 207 ). The client program of the wireless device  157  displays the retrieved telephone number and a call button. If employee A selects the call button to call the device with the retrieved telephone number, i.e., the wired device  155 , the client program sends a request to the management server  140  to call the wired device  155  (S 209 ). 
     Upon receipt of the request, the management server  140  simultaneously calls the wireless device  157  via circuit switched network  110  and employee B′s wired device  155  via wired communication networks  130  and PBX  151  (S 211 , S 213 ). Alternatively, calls to the wireless device  157  and the wired device  155  are made at different times. For example, employee A′s wireless device  157  may be called first, and if there is a response from employee A′s device, employee B′s wired device  155  may be called subsequently while the call to employee A is put on hold. Order of calls may vary depending on the types of services and implementations of the present disclosure. 
     If a response is received from employee B′s wired device  155 , the management server  140  connects the wired device  155  to employee A′s wireless device  157  (S 217 ). 
     If there is no response from employee B′s wired device  155 , the management server  140  retrieves the telephone number of employee B′s wireless device  153  from the address book database  141 , and then the server  140  calls employee B′s wireless device  153  (S 215 ). Preferably, the server  140  calls employee B′s wireless device  153  if there is no response from the wired device  155  for a predetermined period of time. If there is a response from the wireless device  153 , the server  140  connects employee B′s wireless device  153  to employee A′s wireless device  157  (S 219 ). 
     As described above, a company can manage an address book for its employees and connect calls between the employees through a central server. This allows the company to effectively manage the cost of business-related telephone bills. Also, callers can avoid having to call recipients&#39; multiple devices separately because the wireless device  153  is called subsequently when there is no response received from the wired device  155 . 
       FIG. 3  illustrates another example of a flow chart describing a method of call connection between employees in the system presented in  FIG. 1 . Employee A uses a client program on the wireless device  157 . The client program establishes connection to packet network  120  (S 301 ), and connection to the management server  140  via packet network  120  (S 303 ). 
     As the wireless device  157  is connected to the management server  140 , the server  140  sends initial screen to the wireless device  157  for an address book search. As described in  FIG. 1 , the initial screen includes a search menu for employees and clients. If employee A enters employee B′s name for a search, an address book search request including employee B′s name is sent to the management server  140  by the client program (S 305 ). 
     Upon receipt of the request including the entered name, the management server  140  retrieves the telephone number corresponding to the entered name from the address book database  141 . Then, the server  140  sends the retrieved telephone number to employee A′s wireless device  157  (S 307 ). 
     The client program of the wireless device  157  displays the retrieved telephone number and a call button. If employee A selects the call button to call the device with the retrieved telephone number, i.e., the wired device  155 , the client program sends a request to the management server  140  to call the wired device  155  (S 309 ). 
     Upon receipt of the request, the management server  140  retrieves the telephone number of employee B′s wireless device from the address book database  141 . Then, the server  140  calls employee A′s wireless device  157  via circuit switched network  110  (S 311 ). Also, the server  140  calls employee B′s wired device  155  via wired communication networks  130  and PBX  151  (S 313 ), while simultaneously calling employee B′s wireless device  153  via circuit switched network  110  (S 315 ). Accordingly, employee B′s wired and wireless devices  153  and  155  receive calls simultaneously. 
     If responses are received from employee A′s wireless device  157  and employee B′s wired device  155  (S 317 ,  319 ), the management server  140  connects the call between those devices  155  and  157  (S 323 ) and disconnects the call between the server  140  and employee B′s wireless device  153  (S 321 ). 
     If responses are received from employee A′s wireless device  157  and employee B′s wireless device  153  but no response is received from employee B′s wired device  155 , the management server  140  connects the call between those devices  153 ,  157  and disconnects the call between the server  140  and employee B′s wired device  155 . 
     Calls to employee A′s device and employee B′s devices may be made at different times. For example, employee A′s wireless device  157  may be called first, and if there is a response from employee A′s device, employee B′s wired device  155  and wireless device  153  may be called subsequently while the call to employee A is put on hold. Order of calls may vary depending on the types of services and implementations of the present disclosure. 
     As described above, a company can manage an address book database for its employees and connect calls between the employees through a central server, such as the management server  140 . This allows the company to effectively manage the cost of business-related telephone bills. Also, callers do not have to call recipients&#39; multiple devices separately because the wireless device  153  is automatically called when there is no response received from the wired device  155 . 
       FIG. 4  illustrates a call service system according to another embodiment of the present disclosure. Elements that are common in  FIG. 1  and  FIG. 4  have the same functionality, and thus a detailed description will be omitted for those common elements. 
     For the system described in  FIG. 4 , the wired device  157  is assumed to be a first user&#39;s device, and the wireless device  430  and the wired device  450  are assumed to be a second user&#39;s device. The first user may be an employee of a company and the second user may be a client of the company. An example of a call connection attempt from the employee&#39;s wireless device  157  to the client&#39;s devices  430  and  450  is explained below. 
     In order to call a client, the employee runs a client program at the wireless device  157 , so that the wireless device  157  may be connected to a functional unit, such as the management server  410 , via packet network  120 . Then, as described in  FIG. 1 , the initial screen is displayed on the employee&#39;s wireless device  157  to provide a search menu. When the employee enters a client&#39;s name for a search, the client program sends this information to the management server  410 . 
     With the information received from the client program, the management server  410  retrieves the telephone number of the client&#39;s wired device and/or wireless device from a database, such as the address book database  141 . Then, the management server  410  may send the retrieved number to the wireless device  157 . 
     When the management server  410  receives a call request from employee&#39;s wireless device  157  to call the client&#39;s device, the server  410  calls employee&#39;s wireless device  157  via circuit switched network  110 . The server  410  also calls the client&#39;s wireless devices  430  via circuit switched network  110 . Alternatively or in addition to that, the server  410  calls the client&#39;s wired device  450  via wired communication networks  130 . The server  410  retrieves the telephone number of the employee&#39;s wired device (not shown) from the address book database  141  and send that number to the client&#39;s devices  430  and  450  as a caller&#39;s telephone number, so that the retrieved employee&#39;s wired telephone number can be indicated on the client&#39;s devices  430 ,  450  as a caller&#39;s telephone number. In other words, when calling client&#39;s devices  430 ,  450 , the management server  410  replaces employee&#39;s wireless telephone number with the wired telephone number so that the wired telephone number may be displayed as a caller&#39;s telephone number. 
     Accordingly, although not described in  FIG. 4 , the management server  410  may include a replacement module that can send an employee&#39;s wired telephone number as a caller&#39;s telephone number when the employee calls a client using a wireless device. 
       FIG. 5  illustrates an example of a flow chart describing a method of call connection from an employee to a client in the system presented in  FIG. 4 . As described in  FIG. 5 , the employee uses the client program on the wireless device  157 . The client program establishes connection to packet network  120  (S 401 ), and connection to the management server  410  via packet network  120  (S 403 ). 
     As the wireless device  157  is connected to the management server  410 , the server  410  sends an initial screen on the wireless device  157  for an address book search. As described in  FIG. 4 , the initial screen includes a search menu for employees and clients. If the employee enters a client&#39;s name for a search, an address book search request including the client&#39;s name is sent to the management server  410  by the client program (S 405 ). 
     Upon receipt of the request including the entered name, the management server  410  retrieves the telephone number that corresponds to the entered name from the address book database  141 . Then, the server  410  sends the retrieved telephone number to the wireless device  157  (S 407 ). The client program of the wireless device  157  displays the retrieved telephone number and a call button. 
     If the employee selects the call button to call the device with the retrieved telephone number, the client program of the wireless device  157  sends a request to the management server  140  to call the above selected telephone number (S 409 ). 
     The management server  410  verifies if the call request signal is for a client rather than another employee, and retrieves the employee&#39;s wired telephone number from the address book database  141  (S 411 ). 
     Then, the management server  410  calls the wireless device  157  via circuit switched network  110  and simultaneously calls the client&#39;s wireless device  430  and/or wired device  450  via circuit switched network  110  and/or wired communication networks  130  (S 413 , S 415 ). Then, the management server  410  connects the call between the employee and the client (S 417 ). 
     When calling the client&#39;s devices  430  and/or  450 , the management server  410  sends the employee&#39;s wired telephone number, retrieved from the address book database  141  at  5411 , rather than the employee&#39;s wireless telephone number, to be indicated as a caller&#39;s number. 
     The calls to the wireless device  157  and the client&#39;s devices  430 ,  450  may be made at different times. For example, the employee&#39;s wireless device  157  may be called first, and the client&#39;s devices  430 ,  450  may be called subsequently while the call to the employee is put on hold. If there is a response from the client&#39;s device, then the call between the employee and the client can be connected. 
     As described above, a company can manage an address book of its employees and clients and connect calls between an employee and a client through a central server. This allows the company to minimize the risk of losing client information after employees leave the company. Also, the company may better protect its employees&#39; privacy because the employees&#39; telephone numbers at work (in most cases, wired devices) are sent to the clients, even when the employees call their clients using their personal mobile devices. 
       FIG. 6  illustrates a call service system according to another embodiment of the present disclosure. Elements that are common in  FIG. 1  and  FIG. 4  have the same functionality, and thus a detailed description will be omitted for those common elements. 
     In the embodiment described in  FIG. 6 , the wireless device  520  and the wired device  530  are assumed to be a first user&#39;s devices, and the wireless device  550  and the wired device  540  are assumed to be a second user&#39;s devices. The first user may be a client of a company and the second user may be an employee of the company. An example of a call connection attempt from the first user&#39;s devices  520 ,  530  to the second user&#39;s wired device  540  in the system of  FIG. 6  will be explained below. 
     If the client calls the employee&#39;s wired telephone number from the client&#39;s device  520  or  530 , the client&#39;s device sends a call request signal to the communication network  110  or  130 . Then, a controller (not shown) of the communication network  110  or  130  checks whether the recipient&#39;s telephone number is registered for a company call service. If the recipient&#39;s telephone number is registered for the company call service, the controller of the communication network  110  or  130  routes the call request signal to a functional unit, such as the management server  510 . 
     The management server  510  retrieves a caller&#39;s telephone number from the signal received from the client&#39;s device and stores the retrieved number in the address book database  141 . If the retrieved caller&#39;s number has already been stored in the database  141 , the management server  510  may merely register the number in the incoming call log without adding new contact information. If the retrieved caller&#39;s number has not yet been stored in the database  141 , the management server  510  may store the number in the unidentified client list of the address book database  141  so that the called employee may later edit and store the information as new client information. 
     Upon receipt of the signal including the recipient&#39;s telephone number, the management server  510  attempts to connect with the employee&#39;s wired device  540  via wired communication network  130  by dialing the recipient&#39;s number, i.e., the employee&#39;s wired telephone number. If no response is received from the employee&#39;s wired device  540 , the management server  510  attempts to connect with the employee&#39;s wireless device  550  via circuit switched network  110 , using the employee&#39;s wireless telephone number retrieved from the address book database  141 . As such, the server  510  connects the client&#39;s device  520  or  530  to the employee&#39;s device  540  or  550  that has responded. 
     In another embodiment of the disclosure, when the management server receives a signal including the telephone number of the employee&#39;s wired device  540 , the management server  510  retrieves the employee&#39;s wireless telephone number from the address book database  141 . Then, the server  510  calls the employee&#39;s wired device  540  and the employee&#39;s wireless device  550  simultaneously. If there is a response from at least one of employee&#39;s devices  540  and  550 , the server  510  connects the responsive device with the client&#39;s device  520  or  530  and disconnects the call between the server  140  and the non-responsive device. 
     When the management server  510  receives the signal from the client&#39;s device, the server  510  retrieves the caller&#39;s telephone number from the signal and retrieves the caller&#39;s information that corresponds to the retrieved telephone number from the address book database  141 . Then, the server  510  sends the retrieved caller&#39;s information to the employee&#39;s devices  540  and/or  550 . For example, the caller&#39;s name or an employee&#39;s memo about the caller that were stored in the database  141  may be sent to and displayed at the employee&#39;s devices  540  and/or  550 , as well as the caller&#39;s telephone number. 
     Accordingly, the management server  510  allows the employee to effectively deal with the calling client by sending the information about the client stored in the address book database  141 . Specifically, the server  510  may retrieve the client&#39;s information upon receipt of the signal from the client and provide the information to the employee&#39;s devices  540  and/or  550  when directing the call to the devices. 
     Accordingly, although not described in  FIG. 6 , the management server  510  may include a client telephone registration module that can retrieve client&#39;s telephone number and store it in the address book database  141 . The server  510  may also include a caller&#39;s information searching module that retrieve the caller&#39;s information from the address book database  141  by using the retrieved caller&#39;s telephone number. 
       FIG. 7  illustrates an example of a flow chart describing a method of call connection from a client to an employee in the system presented in  FIG. 6 . As described in  FIG. 7 , in order to call an employee, a client may enter the employee&#39;s wired telephone number on the client&#39;s device  520  or  530  and select a call button, thereby generating a call request signal. When the call request signal is sent to communication network  110  or  130  from the client&#39;s device  520  or  530 , the controller of the communication network  110  or  130  checks whether the recipient&#39;s number included in the signal is registered for a company call service. If so, the controller of the communication network  110  or  130  sends the signal to the management server  510  (S 601 ). 
     The management server  510  retrieves a caller&#39;s telephone number from the signal sent from the client&#39;s device  520  or  530  (S 603 ) and stores the retrieved number in the address book database  141  (S 605 ). The server  510  may either register the number in the incoming call log or in a folder for unregistered clients so that the called employee may later store the telephone number as new client information. 
     Then, the management server  510  calls the employee&#39;s wired device  540  via wired communication networks  130  and PBX  151  (S 607 ). If there is a response from the employee&#39;s wired device  540 , the server  510  connects the call between the client&#39;s device  520  or  530  and the employee&#39;s device  540  (S 611 ). 
     However, if there is no response from the employee&#39;s wired device  540  for a predetermined period of time, the server  510  calls the employee&#39;s wireless device  550  via circuit switched network  110 , using the employee&#39;s wireless telephone number retrieved from the address book database  141  (S 609 ). If a response is received from the employee&#39;s wireless device  550 , the server  510  sets up the call between the client&#39;s device  520  or  530  and the employee&#39;s wireless device  550  (S 613 ). 
     With this illustrative implementation of the present disclosure, employees may use the company&#39;s wired telephone numbers for business purposes, and clients may use the employees&#39; wired telephone numbers to contact them. Particularly, clients may contact the employees without knowing their wireless telephone numbers because the management server  510  attempts to call the employees&#39; wired devices first and then attempts to call the employees&#39; wireless devices if there is no response from the wired devices. Accordingly, the employees may better protect their privacy because their personal wireless telephone numbers are not exposed. Also, the company may minimize the risk of losing client information after employees leave the company because call logs including clients&#39; telephone numbers are recorded when the clients attempt to contact employees. 
     Although the example of the flow chart of  FIG. 7  describes that employee&#39;s wired device  540  is called first and the wireless device  550  is called subsequently if there is no response from the wired device  540 , there may be alternatives. For example, as described in  FIG. 3 , the employee&#39;s wired device  540  and wireless device  550  may be called simultaneously after retrieving the employee&#39;s wireless number from the address book database  141 . If there is a response from any one of employee&#39;s devices  540  and  550 , the server  510  may connect the responsive device with the client&#39;s device  520  or  530  and disconnect the call between the server  140  and the non-responsive device. 
       FIG. 8  illustrates another example of a flow chart describing a method of call connection from a client to an employee in the system presented in  FIG. 6 . As described in  FIG. 8 , in order to call an employee, a client enters the employee&#39;s wired telephone number on the communication device  520  or  530  and selects a call button, sending a call request signal. When the call request signal is sent to communication network  110  or  130  from the client&#39;s device  520  or  530 , the controller of the communication network  110  or  130  checks whether the recipient&#39;s number included in the signal is registered for a company call service. If so, the controller of the communication network  110  or  130  sends the signal to the management server  510  (S 801 ). 
     As the management server  510  receives the call request signal, the server  510  retrieves the caller&#39;s telephone number from the signal (S 803 ). The management server  510  then retrieves information related to the caller (i.e., the client) from the address book database  141  using the caller&#39;s telephone number (S 805 ). The information related to the caller may be the name of the caller or a memo prepared by an employee about the caller. 
     Then, the management server  510  calls the employee&#39;s wired device  540  via wired communication networks  130  and PBX  151 , and also sends the information related to the caller to the employee&#39;s wired device  540  (S 807 ). Accordingly, the caller&#39;s information may be displayed on the employee&#39;s wired device  540 , and this allows the employee to have the caller&#39;s information even if the relevant information was not stored in the employee&#39;s wired device  540  (S 809 ). If there is a response from the employee&#39;s wired device  540 , the server  510  connects the client&#39;s device  520  or  530  to the employee&#39;s wired device  540  (S 815 ). 
     However, if there is no response from the employee&#39;s wired device  540  for a predetermined period of time, the management server  510  calls the employee&#39;s wireless device  550  via circuit switched network  110 , using the employee&#39;s wireless telephone number retrieved from the address book database  141 . Here, the server  510  also sends the retrieved caller&#39;s information to the employee&#39;s wireless device  550  (S 811 ). Accordingly, the caller&#39;s information may be displayed on the employee&#39;s wireless device  550 , and this allows the employee to have the caller&#39;s information even though the relevant information was not stored in the wireless device  550  (S 813 ). If there is a response from the employee&#39;s wireless device  550 , the server  510  connects the client&#39;s device  520  or  530  to the employee&#39;s wireless device  550  (S 817 ). 
     As described above, clients may reach the employees&#39; wireless communication devices by calling the employees&#39; wired telephone numbers. Also, the management server  510  allows the employees to effectively deal with the clients by sending the clients&#39; information stored in the address book database  141  when directing the calls to the employees. Specifically, the server  510  retrieves clients&#39; information upon receipt of the call request signals from the clients and provides the relevant information to the employees&#39; devices  540  and  550 . 
     Although the example of the flow chart of  FIG. 8  describes that employee&#39;s wired device  540  is called first and the wireless device  550  is called subsequently if there is no response from the wired device  540 , there may be alternatives. For example, as described in  FIG. 3 , calls to employee&#39;s wired device  540  and wireless device  550  can be made simultaneously after retrieving the employee&#39;s wireless number from the address book database  141 . If there is a response from any one of employee&#39;s devices  540  and  550 , the server  510  may connect the responsive device with the client&#39;s device  520  or  530  then, disconnect the call between the server  140  and the non-responsive device. 
     The methods described above as various embodiments of the present disclosure may be implemented as a set of computer-executable instructions and stored in a computer readable medium such as CD-ROM, RAM, ROM, Floppy disk, Hard drive, or magneto-optical disc. 
     Although a number of embodiments of the present disclosure have been disclosed herein, the above description is merely illustrative. It will be understood that various modifications may be made without departing from the spirit and scope of the claims. Accordingly, other embodiments are within the scope of the following claims.